(Slip Opinion)              OCTOBER TERM, 2005                                       1

                                       Syllabus

         NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
       being done in connection with this case, at the time the opinion is issued.
       The syllabus constitutes no part of the opinion of the Court but has been
       prepared by the Reporter of Decisions for the convenience of the reader.
       See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.


SUPREME COURT OF THE UNITED STATES

                                       Syllabus

 HAMDAN v. RUMSFELD, SECRETARY OF DEFENSE,
                   ET AL.

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
          THE DISTRICT OF COLUMBIA CIRCUIT

      No. 05–184.      Argued March 28, 2006—Decided June 29, 2006
Pursuant to Congress’ Joint Resolution authorizing the President to
  “use all necessary and appropriate force against those nations, or
  ganizations, or persons he determines planned, authorized, commit
  ted or aided” the September 11, 2001, al Qaeda terrorist attacks
  (AUMF), U. S. Armed Forces invaded Afghanistan. During the hos
  tilities, in 2001, militia forces captured petitioner Hamdan, a Yemeni
  national, and turned him over to the U. S. military, which, in 2002,
  transported him to prison in Guantanamo Bay, Cuba. Over a year
  later, the President deemed Hamdan eligible for trial by military
  commission for then-unspecified crimes. After another year, he was
  charged with conspiracy “to commit . . . offenses triable by military
  commission.” In habeas and mandamus petitions, Hamdan asserted
  that the military commission lacks authority to try him because (1)
  neither congressional Act nor the common law of war supports trial
  by this commission for conspiracy, an offense that, Hamdan says, is
  not a violation of the law of war; and (2) the procedures adopted to
  try him violate basic tenets of military and international law, includ
  ing the principle that a defendant must be permitted to see and hear
  the evidence against him.
     The District Court granted habeas relief and stayed the commis
  sion’s proceedings, concluding that the President’s authority to estab
  lish military commissions extends only to offenders or offenses triable
  by such a commission under the law of war; that such law includes
  the Third Geneva Convention; that Hamdan is entitled to that Con
  vention’s full protections until adjudged, under it, not to be a prisoner
  of war; and that, whether or not Hamdan is properly classified a pris
  oner of war, the commission convened to try him was established in
2                        HAMDAN v. RUMSFELD

                                  Syllabus

    violation of both the Uniform Code of Military Justice (UCMJ), 10
    U. S. C. §801 et seq., and Common Article 3 of the Third Geneva Con
    vention because it had the power to convict based on evidence the ac
    cused would never see or hear. The D. C. Circuit reversed. Although
    it declined the Government’s invitation to abstain from considering
    Hamdan’s challenge, cf. Schlesinger v. Councilman, 420 U. S. 738, the
    appeals court ruled, on the merits, that Hamdan was not entitled to re
    lief because the Geneva Conventions are not judicially enforceable. The
    court also concluded that Ex parte Quirin, 317 U. S. 1, foreclosed any
    separation-of-powers objection to the military commission’s jurisdiction,
    and that Hamdan’s trial before the commission would violate neither
    the UCMJ nor Armed Forces regulations implementing the Geneva
    Conventions.
Held: The judgment is reversed, and the case is remanded.
415 F. 3d 33, reversed and remanded.
     JUSTICE STEVENS delivered the opinion of the Court, except as to
  Parts V and VI–D–iv, concluding:
     1. The Government’s motion to dismiss, based on the Detainee
  Treatment Act of 2005 (DTA), is denied. DTA §1005(e)(1) provides
  that “no court . . . shall have jurisdiction to hear or consider . . . an
  application for . . . habeas corpus filed by . . . an alien detained . . . at
  Guantanamo Bay.” Section 1005(h)(2) provides that §§1005(e)(2) and
  (3)—which give the D. C. Circuit “exclusive” jurisdiction to review the
  final decisions of, respectively, combatant status review tribunals
  and military commissions—“shall apply with respect to any claim
  whose review is . . . pending on” the DTA’s effective date, as was
  Hamdan’s case. The Government’s argument that §§1005(e)(1) and
  (h) repeal this Court’s jurisdiction to review the decision below is re
  butted by ordinary principles of statutory construction. A negative
  inference may be drawn from Congress’ failure to include §1005(e)(1)
  within the scope of §1005(h)(2). Cf., e.g., Lindh v. Murphy, 521 U. S.
  320, 330. “If . . . Congress was reasonably concerned to ensure that
  [§§1005(e)(2) and (3)] be applied to pending cases, it should have been
  just as concerned about [§1005(e)(1)], unless it had the different in
  tent that the latter [section] not be applied to the general run of
  pending cases.” Id., at 329. If anything, the evidence of deliberate
  omission is stronger here than it was in Lindh. The legislative his
  tory shows that Congress not only considered the respective temporal
  reaches of §§1005(e)(1), (2), and (3) together at every stage, but omit
  ted paragraph (1) from its directive only after having rejected earlier
  proposed versions of the statute that would have included what is
  now paragraph (1) within that directive’s scope. Congress’ rejection
  of the very language that would have achieved the result the Gov
  ernment urges weighs heavily against the Government’s interpreta
                   Cite as: 548 U. S. ____ (2006)                      3

                              Syllabus

tion. See Doe v. Chao, 540 U. S. 614, 621–623. Pp. 7–20.
   2. The Government argues unpersuasively that abstention is ap
propriate under Councilman, which concluded that, as a matter of
comity, federal courts should normally abstain from intervening in
pending courts-martial against service members, see 420 U. S., at
740. Neither of the comity considerations Councilman identified
weighs in favor of abstention here. First, the assertion that military
discipline and, therefore, the Armed Forces’ efficient operation, are
best served if the military justice system acts without regular inter
ference from civilian courts, see id., at 752, is inapt because Hamdan
is not a service member. Second, the view that federal courts should
respect the balance Congress struck when it created “an integrated
system of military courts and review procedures” is inapposite, since
the tribunal convened to try Hamdan is not part of that integrated
system. Rather than Councilman, the most relevant precedent is Ex
parte Quirin, where the Court, far from abstaining pending the con
clusion of ongoing military proceedings, expedited its review because
of (1) the public importance of the questions raised, (2) the Court’s
duty, in both peace and war, to preserve the constitutional safe
guards of civil liberty, and (3) the public interest in a decision on
those questions without delay, 317 U. S, at 19. The Government has
identified no countervailing interest that would permit federal courts
to depart from their general duty to exercise the jurisdiction Con
gress has conferred on them. Pp. 20–25.
   3. The military commission at issue is not expressly authorized by
any congressional Act. Quirin held that Congress had, through Arti
cle of War 15, sanctioned the use of military commissions to try of
fenders or offenses against the law of war. 317 U. S., at 28. UCMJ
Art. 21, which is substantially identical to the old Art. 15, reads: “The
jurisdiction [of] courts-martial shall not be construed as depriving
military commissions . . . of concurrent jurisdiction in respect of of
fenders or offenses that by statute or by the law of war may be tried
by such . . . commissions.” 10 U. S. C. §821. Contrary to the Gov
ernment’s assertion, even Quirin did not view that authorization as a
sweeping mandate for the President to invoke military commissions
whenever he deems them necessary. Rather, Quirin recognized that
Congress had simply preserved what power, under the Constitution
and the common law of war, the President already had to convene
military commissions—with the express condition that he and those
under his command comply with the law of war. See 317 U. S., at
28–29. Neither the AUMF nor the DTA can be read to provide spe
cific, overriding authorization for the commission convened to try
Hamdan. Assuming the AUMF activated the President’s war powers,
see Hamdi v. Rumsfeld, 542 U. S. 507, and that those powers include
4                         HAMDAN v. RUMSFELD

                                   Syllabus

    authority to convene military commissions in appropriate circum
    stances, see, e.g., id., at 518, there is nothing in the AUMF’s text or leg
    islative history even hinting that Congress intended to expand or alter
    the authorization set forth in UCMJ Art. 21. Cf. Ex parte Yerger, 8
    Wall. 85, 105. Likewise, the DTA cannot be read to authorize this
    commission. Although the DTA, unlike either Art. 21 or the AUMF,
    was enacted after the President convened Hamdan’s commission, it
    contains no language authorizing that tribunal or any other at Guan
    tanamo Bay. Together, the UCMJ, the AUMF, and the DTA at most
    acknowledge a general Presidential authority to convene military
    commissions in circumstances where justified under the Constitution
    and laws, including the law of war. Absent a more specific congres
    sional authorization, this Court’s task is, as it was in Quirin, to de
    cide whether Hamdan’s military commission is so justified. Pp. 25–
    30.
       4. The military commission at issue lacks the power to proceed be
    cause its structure and procedures violate both the UCMJ and the
    four Geneva Conventions signed in 1949. Pp. 49–72.
          (a) The commission’s procedures, set forth in Commission Order
    No. 1, provide, among other things, that an accused and his civilian
    counsel may be excluded from, and precluded from ever learning
    what evidence was presented during, any part of the proceeding the
    official who appointed the commission or the presiding officer decides
    to “close.” Grounds for closure include the protection of classified in
    formation, the physical safety of participants and witnesses, the pro
    tection of intelligence and law enforcement sources, methods, or ac
    tivities, and “other national security interests.” Appointed military
    defense counsel must be privy to these closed sessions, but may, at
    the presiding officer’s discretion, be forbidden to reveal to the client
    what took place therein. Another striking feature is that the rules
    governing Hamdan’s commission permit the admission of any evi
    dence that, in the presiding officer’s opinion, would have probative
    value to a reasonable person. Moreover, the accused and his civilian
    counsel may be denied access to classified and other “protected in
    formation,” so long as the presiding officer concludes that the evi
    dence is “probative” and that its admission without the accused’s
    knowledge would not result in the denial of a full and fair trial. Pp.
    49–52.
          (b) The Government objects to this Court’s consideration of a pro
    cedural challenge at this stage on the grounds, inter alia, that Ham
    dan will be able to raise such a challenge following a final decision
    under the DTA, and that there is no basis to presume, before the trial
    has even commenced, that it will not be conducted in good faith and
    according to law. These contentions are unsound. First, because
                   Cite as: 548 U. S. ____ (2006)                      5

                              Syllabus

Hamdan apparently is not subject to the death penalty (at least as
matters now stand) and may receive a prison sentence shorter than
10 years, he has no automatic right to federal-court review of the
commission’s “final decision” under DTA §1005(e)(3). Second, there is
a basis to presume that the procedures employed during Hamdan’s
trial will violate the law: He will be, and indeed already has been, ex
cluded from his own trial. Thus, review of the procedures in advance
of a “final decision” is appropriate. Pp. 52–53.
     (c) Because UCMJ Article 36 has not been complied with here,
the rules specified for Hamdan’s commission trial are illegal. The
procedures governing such trials historically have been the same as
those governing courts-martial. Although this uniformity principle is
not inflexible and does not preclude all departures from courts-
martial procedures, any such departure must be tailored to the exi
gency that necessitates it. That understanding is reflected in Art.
36(b), which provides that the procedural rules the President prom
ulgates for courts-martial and military commissions alike must be
“uniform insofar as practicable,” 10 U. S. C. §836(b). The “practica
bility” determination the President has made is insufficient to justify
variances from the procedures governing courts-martial. The Presi
dent here has determined, pursuant to the requirement of Art. 36(a),
that it is impracticable to apply the rules and principles of law that
govern “the trial of criminal cases in the United States district
courts” to Hamdan’s commission. The President has not, however,
made a similar official determination that it is impracticable to apply
the rules for courts-martial. And even if subsection (b)’s require
ments could be satisfied without an official practicability determina
tion, that subsection’s requirements are not satisfied here. Nothing
in the record demonstrates that it would be impracticable to apply
court-martial rules here. There is no suggestion, e.g., of any logistical
difficulty in securing properly sworn and authenticated evidence or in
applying the usual principles of relevance and admissibility. It is not
evident why the danger posed by international terrorism, consider
able though it is, should require, in the case of Hamdan’s trial, any
variance from the courts-martial rules. The absence of any showing
of impracticability is particularly disturbing when considered in light
of the clear and admitted failure to apply one of the most fundamen
tal protections afforded not just by the Manual for Courts-Martial but
also by the UCMJ itself: The right to be present. See 10 U. S. C. A.
§839(c). Because the jettisoning of so basic a right cannot lightly be
excused as “practicable,” the courts-martial rules must apply. Since
it is undisputed that Commission Order No. 1 deviates in many sig
nificant respects from those rules, it necessarily violates Art. 36(b).
Pp. 53–62.
6                        HAMDAN v. RUMSFELD

                                  Syllabus

          (d) The procedures adopted to try Hamdan also violate the Ge
    neva Conventions. The D. C. Circuit dismissed Hamdan’s challenge
    in this regard on the grounds, inter alia, that the Conventions are not
    judicially enforceable and that, in any event, Hamdan is not entitled
    to their protections. Neither of these grounds is persuasive. Pp. 62–
    68.
             (i) The appeals court relied on a statement in Johnson v. Eisen
    trager, 339 U. S. 763, 789, n. 14, suggesting that this Court lacked
    power even to consider the merits of a Convention argument because
    the political and military authorities had sole responsibility for ob
    serving and enforcing prisoners’ rights under the Convention. How
    ever, Eisentrager does not control here because, regardless of the na
    ture of the rights conferred on Hamdan, cf. United States v. Rauscher,
    119 U. S. 407, they are indisputably part of the law of war, see
    Hamdi, 542 U. S., at 520–521, compliance with which is the condition
    upon which UCMJ Art. 21 authority is granted. Pp. 63–65.
             (ii) Alternatively, the appeals court agreed with the Govern
    ment that the Conventions do not apply because Hamdan was cap
    tured during the war with al Qaeda, which is not a Convention signa
    tory, and that conflict is distinct from the war with signatory
    Afghanistan. The Court need not decide the merits of this argument
    because there is at least one provision of the Geneva Conventions
    that applies here even if the relevant conflict is not between signato
    ries. Common Article 3, which appears in all four Conventions, pro
    vides that, in a “conflict not of an international character occurring in
    the territory of one of the High Contracting Parties [i.e., signatories],
    each Party to the conflict shall be bound to apply, as a minimum,”
    certain provisions protecting “[p]ersons . . . placed hors de combat by
    . . . detention,” including a prohibition on “the passing of sentences
    . . . without previous judgment . . . by a regularly constituted court af
    fording all the judicial guarantees . . . recognized as indispensable by
    civilized peoples.” The D. C. Circuit ruled Common Article 3 inappli
    cable to Hamdan because the conflict with al Qaeda is international
    in scope and thus not a “conflict not of an international character. ”
    That reasoning is erroneous. That the quoted phrase bears its literal
    meaning and is used here in contradistinction to a conflict between
    nations is demonstrated by Common Article 2, which limits its own
    application to any armed conflict between signatories and provides
    that signatories must abide by all terms of the Conventions even if
    another party to the conflict is a nonsignatory, so long as the nonsig
    natory “accepts and applies” those terms. Common Article 3, by con
    trast, affords some minimal protection, falling short of full protection
    under the Conventions, to individuals associated with neither a sig
    natory nor even a nonsignatory who are involved in a conflict “in the
                   Cite as: 548 U. S. ____ (2006)                      7

                              Syllabus

territory of” a signatory. The latter kind of conflict does not involve a
clash between nations (whether signatories or not). Pp. 65–68.
        (iii) While Common Article 3 does not define its “regularly con
stituted court” phrase, other sources define the words to mean an
“ordinary military cour[t]” that is “established and organized in ac
cordance with the laws and procedures already in force in a country.”
The regular military courts in our system are the courts-martial es
tablished by congressional statute. At a minimum, a military com
mission can be “regularly constituted” only if some practical need ex
plains deviations from court-martial practice. No such need has been
demonstrated here. Pp. 69–70.
        (iv) Common Article 3’s requirements are general, crafted to
accommodate a wide variety of legal systems, but they are require
ments nonetheless. The commission convened to try Hamdan does
not meet those requirements. P. 72.
      (d) Even assuming that Hamden is a dangerous individual who
would cause great harm or death to innocent civilians given the op
portunity, the Executive nevertheless must comply with the prevail
ing rule of law in undertaking to try him and subject him to criminal
punishment. P. 72.
   JUSTICE STEVENS, joined by JUSTICE SOUTER, JUSTICE GINSBURG,
and JUSTICE BREYER, concluded in Parts V and VI–D–iv:
   1. The Government has not charged Hamdan with an “offense . . .
that by the law of war may be tried by military commission,” 10
U. S. C. §821. Of the three sorts of military commissions used his
torically, the law-of-war type used in Quirin and other cases is the
only model available to try Hamdan. Among the preconditions, in
corporated in Article of War 15 and, later, UCMJ Art. 21, for such a
tribunal’s exercise of jurisdiction are, inter alia, that it must be lim
ited to trying offenses committed within the convening commander’s
field of command, i.e., within the theater of war, and that the offense
charged must have been committed during, not before or after, the
war. Here, Hamdan is not alleged to have committed any overt act in
a theater of war or on any specified date after September 11, 2001.
More importantly, the offense alleged is not triable by law-of-war
military commission. Although the common law of war may render
triable by military commission certain offenses not defined by stat
ute, Quirin, 317 U. S., at 30, the precedent for doing so with respect
to a particular offense must be plain and unambiguous, cf., e.g., Lov
ing v. United States, 517 U. S. 748, 771. That burden is far from satis
fied here. The crime of “conspiracy” has rarely if ever been tried as
such in this country by any law-of-war military commission not exer
cising some other form of jurisdiction, and does not appear in either
the Geneva Conventions or the Hague Conventions—the major trea
8                        HAMDAN v. RUMSFELD

                                  Syllabus

    ties on the law of war. Moreover, that conspiracy is not a recognized
    violation of the law of war is confirmed by other international
    sources, including, e.g., the International Military Tribunal at Nur
    emberg, which pointedly refused to recognize conspiracy to commit
    war crimes as such a violation. Because the conspiracy charge does
    not support the commission’s jurisdiction, the commission lacks au
    thority to try Hamdan. Pp. 30–49.
       2. The phrase “all the guarantees . . . recognized as indispensable
    by civilized peoples” in Common Article 3 of the Geneva Conventions
    is not defined, but it must be understood to incorporate at least the
    barest of the trial protections recognized by customary international
    law. The procedures adopted to try Hamdan deviate from those gov
    erning courts-martial in ways not justified by practical need, and
    thus fail to afford the requisite guarantees. Moreover, various provi
    sions of Commission Order No. 1 dispense with the principles, which
    are indisputably part of customary international law, that an accused
    must, absent disruptive conduct or consent, be present for his trial
    and must be privy to the evidence against him. Pp. 70–72.
       JUSTICE KENNEDY, agreeing that Hamdan’s military commission is
    unauthorized under the Uniform Code of Military Justice, 10 U. S. C.
    §§836 and 821, and the Geneva Conventions, concluded that there is
    therefore no need to decide whether Common Article 3 of the Conven
    tions requires that the accused have the right to be present at all
    stages of a criminal trial or to address the validity of the conspiracy
    charge against Hamdan. Pp. 17–19.

   STEVENS, J., announced the judgment of the Court and delivered the
opinion of the Court with respect to Parts I through IV, VI through VI–
D–iii, VI–D–v, and VII, in which KENNEDY, SOUTER, GINSBURG, and
BREYER, JJ., joined, and an opinion with respect to Parts V and VI–D–
iv, in which SOUTER, GINSBURG, and BREYER, JJ., joined. BREYER, J.,
filed a concurring opinion, in which KENNEDY, SOUTER, and GINSBURG,
JJ., joined. KENNEDY, J., filed an opinion concurring in part, in which
SOUTER, GINSBURG, and BREYER, JJ., joined as to Parts I and II. SCALIA,
J., filed a dissenting opinion, in which THOMAS and ALITO, JJ., joined.
THOMAS, J., filed a dissenting opinion, in which SCALIA, J., joined, and
in which ALITO, J., joined as to all but Parts I, II–C–1, and III–B–2.
ALITO, J., filed a dissenting opinion, in which SCALIA and THOMAS, JJ.,
joined as to Parts I through III. ROBERTS, C. J., took no part in the
consideration or decision of the case.
                       Cite as: 548 U. S. ____ (2006)                              1

                           Opinion of STEVENS, J.

    NOTICE: This opinion is subject to formal revision before publication in the
    preliminary print of the United States Reports. Readers are requested to
    notify the Reporter of Decisions, Supreme Court of the United States, Wash
    ington, D. C. 20543, of any typographical or other formal errors, in order
    that corrections may be made before the preliminary print goes to press.


SUPREME COURT OF THE UNITED STATES
                                  _________________

                                  No. 05–184
                                  _________________


 SALIM AHMED HAMDAN, PETITIONER v. DONALD
  H. RUMSFELD, SECRETARY OF DEFENSE, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

    APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT

                                [June 29, 2006] 


  JUSTICE STEVENS announced the judgment of the Court
and delivered the opinion of the Court with respect to
Parts I through IV, Parts VI through VI–D–iii, Part VI–D–
v, and Part VII, and an opinion with respect to Parts V
and VI–D–iv, in which JUSTICE SOUTER, JUSTICE
GINSBURG, and JUSTICE BREYER join.
  Petitioner Salim Ahmed Hamdan, a Yemeni national, is
in custody at an American prison in Guantanamo Bay,
Cuba. In November 2001, during hostilities between the
United States and the Taliban (which then governed
Afghanistan), Hamdan was captured by militia forces and
turned over to the U. S. military. In June 2002, he was
transported to Guantanamo Bay. Over a year later, the
President deemed him eligible for trial by military com
mission for then-unspecified crimes. After another year
had passed, Hamdan was charged with one count of con
spiracy “to commit . . . offenses triable by military com
mission.” App. to Pet. for Cert. 65a.
  Hamdan filed petitions for writs of habeas corpus and
mandamus to challenge the Executive Branch’s intended
means of prosecuting this charge. He concedes that a
2                 HAMDAN v. RUMSFELD

                     Opinion of the Court

court-martial constituted in accordance with the Uniform
Code of Military Justice (UCMJ), 10 U. S. C. §801 et seq.
(2000 ed. and Supp. III), would have authority to try him.
His objection is that the military commission the Presi
dent has convened lacks such authority, for two principal
reasons: First, neither congressional Act nor the common
law of war supports trial by this commission for the crime
of conspiracy—an offense that, Hamdan says, is not a
violation of the law of war. Second, Hamdan contends, the
procedures that the President has adopted to try him
violate the most basic tenets of military and international
law, including the principle that a defendant must be
permitted to see and hear the evidence against him.
  The District Court granted Hamdan’s request for a writ
of habeas corpus. 344 F. Supp. 2d 152 (DC 2004). The
Court of Appeals for the District of Columbia Circuit
reversed. 415 F. 3d 33 (2005). Recognizing, as we did over
a half-century ago, that trial by military commission is an
extraordinary measure raising important questions about
the balance of powers in our constitutional structure,
Ex parte Quirin, 317 U. S. 1, 19 (1942), we granted certio
rari. 546 U. S. ___ (2005).
  For the reasons that follow, we conclude that the mili
tary commission convened to try Hamdan lacks power to
proceed because its structure and procedures violate both
the UCMJ and the Geneva Conventions. Four of us also
conclude, see Part V, infra, that the offense with which
Hamdan has been charged is not an “offens[e] that by . . .
the law of war may be tried by military commissions.” 10
U. S. C. §821.
                            I
   On September 11, 2001, agents of the al Qaeda terrorist
organization hijacked commercial airplanes and attacked
the World Trade Center in New York City and the na
tional headquarters of the Department of Defense in
                 Cite as: 548 U. S. ____ (2006)            3

                     Opinion of the Court

Arlington, Virginia. Americans will never forget the dev
astation wrought by these acts. Nearly 3,000 civilians
were killed.
   Congress responded by adopting a Joint Resolution
authorizing the President to “use all necessary and appro
priate force against those nations, organizations, or per
sons he determines planned, authorized, committed, or
aided the terrorist attacks . . . in order to prevent any
future acts of international terrorism against the United
States by such nations, organizations or persons.” Au
thorization for Use of Military Force (AUMF), 115 Stat.
224, note following 50 U. S. C. §1541 (2000 ed., Supp. III).
Acting pursuant to the AUMF, and having determined
that the Taliban regime had supported al Qaeda, the
President ordered the Armed Forces of the United States
to invade Afghanistan. In the ensuing hostilities, hun
dreds of individuals, Hamdan among them, were captured
and eventually detained at Guantanamo Bay.
   On November 13, 2001, while the United States was
still engaged in active combat with the Taliban, the Presi
dent issued a comprehensive military order intended to
govern the “Detention, Treatment, and Trial of Certain
Non-Citizens in the War Against Terrorism,” 66 Fed. Reg.
57833 (hereinafter November 13 Order or Order). Those
subject to the November 13 Order include any noncitizen
for whom the President determines “there is reason to
believe” that he or she (1) “is or was” a member of al
Qaeda or (2) has engaged or participated in terrorist ac
tivities aimed at or harmful to the United States. Id., at
57834. Any such individual “shall, when tried, be tried by
military commission for any and all offenses triable by
military commission that such individual is alleged to
have committed, and may be punished in accordance with
the penalties provided under applicable law, including
imprisonment or death.” Ibid. The November 13 Order
vested in the Secretary of Defense the power to appoint
4                 HAMDAN v. RUMSFELD

                     Opinion of the Court

military commissions to try individuals subject to the
Order, but that power has since been delegated to John D.
Altenberg, Jr., a retired Army major general and longtime
military lawyer who has been designated “Appointing
Authority for Military Commissions.”
   On July 3, 2003, the President announced his determi
nation that Hamdan and five other detainees at Guan
tanamo Bay were subject to the November 13 Order and
thus triable by military commission. In December 2003,
military counsel was appointed to represent Hamdan.
Two months later, counsel filed demands for charges and
for a speedy trial pursuant to Article 10 of the UCMJ, 10
U. S. C. §810. On February 23, 2004, the legal adviser to
the Appointing Authority denied the applications, ruling
that Hamdan was not entitled to any of the protections of
the UCMJ. Not until July 13, 2004, after Hamdan had
commenced this action in the United States District Court
for the Western District of Washington, did the Govern
ment finally charge him with the offense for which, a year
earlier, he had been deemed eligible for trial by military
commission.
   The charging document, which is unsigned, contains 13
numbered paragraphs. The first two paragraphs recite
the asserted bases for the military commission’s jurisdic
tion—namely, the November 13 Order and the President’s
July 3, 2003, declaration that Hamdan is eligible for trial
by military commission. The next nine paragraphs, collec
tively entitled “General Allegations,” describe al Qaeda’s
activities from its inception in 1989 through 2001 and
identify Osama bin Laden as the group’s leader. Hamdan
is not mentioned in these paragraphs.
   Only the final two paragraphs, entitled “Charge: Con
spiracy,” contain allegations against Hamdan. Paragraph
12 charges that “from on or about February 1996 to on or
about November 24, 2001,” Hamdan “willfully and know
ingly joined an enterprise of persons who shared a com
                    Cite as: 548 U. S. ____ (2006)                 5

                        Opinion of the Court

mon criminal purpose and conspired and agreed with
[named members of al Qaeda] to commit the following
offenses triable by military commission: attacking civil
ians; attacking civilian objects; murder by an unprivileged
belligerent; and terrorism.” App. to Pet. for Cert. 65a.
There is no allegation that Hamdan had any command
responsibilities, played a leadership role, or participated
in the planning of any activity.
  Paragraph 13 lists four “overt acts” that Hamdan is
alleged to have committed sometime between 1996 and
November 2001 in furtherance of the “enterprise and
conspiracy”: (1) he acted as Osama bin Laden’s “bodyguard
and personal driver,” “believ[ing]” all the while that bin
Laden “and his associates were involved in” terrorist acts
prior to and including the attacks of September 11, 2001;
(2) he arranged for transportation of, and actually trans
ported, weapons used by al Qaeda members and by bin
Laden’s bodyguards (Hamdan among them); (3) he “drove
or accompanied [O]sama bin Laden to various al Qaida
sponsored training camps, press conferences, or lectures,”
at which bin Laden encouraged attacks against Ameri
cans; and (4) he received weapons training at al Qaeda
sponsored camps. Id., at 65a–67a.
  After this formal charge was filed, the United States
District Court for the Western District of Washington
transferred Hamdan’s habeas and mandamus petitions to
the United States District Court for the District of Colum
bia. Meanwhile, a Combatant Status Review Tribunal
(CSRT) convened pursuant to a military order issued on
July 7, 2004, decided that Hamdan’s continued detention
at Guantanamo Bay was warranted because he was an
“enemy combatant.”1 Separately, proceedings before the
——————
  1 An “enemy combatant” is defined by the military order as “an indi

vidual who was part of or supporting Taliban or al Qaeda forces, or
associated forces that are engaged in hostilities against the United
6                    HAMDAN v. RUMSFELD

                        Opinion of the Court

military commission commenced.
   On November 8, 2004, however, the District Court
granted Hamdan’s petition for habeas corpus and stayed
the commission’s proceedings. It concluded that the
President’s authority to establish military commissions
extends only to “offenders or offenses triable by military
[commission] under the law of war,” 344 F. Supp. 2d, at
158; that the law of war includes the Geneva Convention
(III) Relative to the Treatment of Prisoners of War, Aug.
12, 1949, [1955] 6 U. S. T. 3316, T. I. A. S. No. 3364 (Third
Geneva Convention); that Hamdan is entitled to the full
protections of the Third Geneva Convention until ad
judged, in compliance with that treaty, not to be a prisoner
of war; and that, whether or not Hamdan is properly
classified as a prisoner of war, the military commission
convened to try him was established in violation of both
the UCMJ and Common Article 3 of the Third Geneva
Convention because it had the power to convict based on
evidence the accused would never see or hear. 344
F. Supp. 2d, at 158–172.
   The Court of Appeals for the District of Columbia Cir
cuit reversed. Like the District Court, the Court of Ap
peals declined the Government’s invitation to abstain from
considering Hamdan’s challenge. Cf. Schlesinger v. Coun
cilman, 420 U. S. 738 (1975). On the merits, the panel
rejected the District Court’s further conclusion that Ham
dan was entitled to relief under the Third Geneva Conven
tion. All three judges agreed that the Geneva Conventions
were not “judicially enforceable,” 415 F. 3d, at 38, and two
thought that the Conventions did not in any event apply to
Hamdan, id., at 40–42; but see id., at 44 (Williams, J.,
——————
States or its coalition partners.” Memorandum from Deputy Secretary
of Defense Paul Wolfowitz re: Order Establishing Combatant Status
Review Tribunal §a (Jul. 7, 2004), available at http://www.defense
link.mil/news/Jul2004/d20040707review.pdf (all Internet materials as
visited June 26, 2006, and available in Clerk of Court’s case file).
                  Cite as: 548 U. S. ____ (2006)            7

                      Opinion of the Court

concurring). In other portions of its opinion, the court con
cluded that our decision in Quirin foreclosed any separation-
of-powers objection to the military commission’s jurisdiction,
and held that Hamdan’s trial before the contemplated com
mission would violate neither the UCMJ nor U. S. Armed
Forces regulations intended to implement the Geneva Con
ventions. 415 F. 3d, at 38, 42–43.
   On November 7, 2005, we granted certiorari to decide
whether the military commission convened to try Hamdan
has authority to do so, and whether Hamdan may rely on
the Geneva Conventions in these proceedings.
                              II
  On February 13, 2006, the Government filed a motion to
dismiss the writ of certiorari. The ground cited for dis
missal was the recently enacted Detainee Treatment Act
of 2005 (DTA), Pub. L. 109–148, 119 Stat. 2739. We post
poned our ruling on that motion pending argument on the
merits, 546 U. S. ___ (2006), and now deny it.
  The DTA, which was signed into law on December 30,
2005, addresses a broad swath of subjects related to de
tainees. It places restrictions on the treatment and inter
rogation of detainees in U. S. custody, and it furnishes
procedural protections for U. S. personnel accused of
engaging in improper interrogation. DTA §§1002–1004,
119 Stat. 2739–2740.          It also sets forth certain
“PROCEDURES FOR STATUS REVIEW OF DETAINEES OUTSIDE
THE UNITED STATES.” §1005, id., at 2740. Subsections (a)
through (d) of §1005 direct the Secretary of Defense to
report to Congress the procedures being used by CSRTs to
determine the proper classification of detainees held in
Guantanamo Bay, Iraq, and Afghanistan, and to adopt
certain safeguards as part of those procedures.
  Subsection (e) of §1005, which is entitled “JUDICIAL
REVIEW OF DETENTION OF ENEMY COMBATANTS,” supplies
the basis for the Government’s jurisdictional argument.
8                  HAMDAN v. RUMSFELD

                     Opinion of the Court

The subsection contains three numbered paragraphs. The
first paragraph amends the judicial code as follows:
      “(1) IN GENERAL.—Section 2241 of title 28, United
    States Code, is amended by adding at the end the
    following:
         .         .        .          .          .
       “ ‘(e) Except as provided in section 1005 of the De
    tainee Treatment Act of 2005, no court, justice, or
    judge shall have jurisdiction to hear or consider—
       “ ‘(1) an application for a writ of habeas corpus filed
    by or on behalf of an alien detained by the Depart
    ment of Defense at Guantanamo Bay, Cuba; or
       “ ‘(2) any other action against the United States or
    its agents relating to any aspect of the detention by
    the Department of Defense of an alien at Guantanamo
    Bay, Cuba, who—
       “ ‘(A) is currently in military custody; or
       “ ‘(B) has been determined by the United States
    Court of Appeals for the District of Columbia Circuit
    in accordance with the procedures set forth in section
    1005(e) of the Detainee Treatment Act of 2005 to have
    been properly detained as an enemy combatant.’ ”
    §1005(e), id., at 2741–2742.
   Paragraph (2) of subsection (e) vests in the Court of
Appeals for the District of Columbia Circuit the “exclusive
jurisdiction to determine the validity of any final decision
of a [CSRT] that an alien is properly designated as an
enemy combatant.” Paragraph (2) also delimits the scope
of that review. See §§1005(e)(2)(C)(i)–(ii), id., at 2742.
   Paragraph (3) mirrors paragraph (2) in structure, but
governs judicial review of final decisions of military
commissions, not CSRTs. It vests in the Court of Appeals
for the District of Columbia Circuit “exclusive jurisdic
tion to determine the validity of any final decision ren
dered pursuant to Military Commission Order No. 1,
                     Cite as: 548 U. S. ____ (2006)                    9

                          Opinion of the Court

dated August 31, 2005 (or any successor military order).”
§1005(e)(3)(A), id., at 2743.2 Review is as of right for any
alien sentenced to death or a term of imprisonment of 10
years or more, but is at the Court of Appeals’ discretion
in all other cases. The scope of review is limited to the
following inquiries:
       “(i) whether the final decision [of the military com
     mission] was consistent with the standards and pro
     cedures specified in the military order referred to in
     subparagraph (A); and
       “(ii) to the extent the Constitution and laws of the
     United States are applicable, whether the use of such
     standards and procedures to reach the final decision
     is consistent with the Constitution and laws of the
     United States.” §1005(e)(3)(D), ibid.
 Finally, §1005 contains an “effective date” provision,
which reads as follows:
       “(1) IN GENERAL.—This section shall take effect on
     the date of the enactment of this Act.
       “(2) REVIEW OF COMBATANT STATUS TRIBUNAL AND
     MILITARY COMMISSION DECISIONS.—Paragraphs (2)
     and (3) of subsection (e) shall apply with respect to
     any claim whose review is governed by one of such
     paragraphs and that is pending on or after the date of
     the enactment of this Act.” §1005(h), id., at 2743–
     2744.3
The Act is silent about whether paragraph (1) of subsec
tion (e) “shall apply” to claims pending on the date of
——————
  2 The military order referenced in this section is discussed further in

Parts III and VI, infra.
  3 The penultimate subsections of §1005 emphasize that the provision

does not “confer any constitutional right on an alien detained as an
enemy combatant outside the United States” and that the “United
States” does not, for purposes of §1005, include Guantanamo Bay.
§§1005(f)–(g).
10                    HAMDAN v. RUMSFELD

                         Opinion of the Court

enactment.
   The Government argues that §§1005(e)(1) and 1005(h)
had the immediate effect, upon enactment, of repealing
federal jurisdiction not just over detainee habeas actions
yet to be filed but also over any such actions then pending
in any federal court—including this Court. Accordingly, it
argues, we lack jurisdiction to review the Court of Appeals’
decision below.
   Hamdan objects to this theory on both constitutional
and statutory grounds. Principal among his constitutional
arguments is that the Government’s preferred reading
raises grave questions about Congress’ authority to im
pinge upon this Court’s appellate jurisdiction, particularly
in habeas cases. Support for this argument is drawn from
Ex parte Yerger, 8 Wall. 85 (1869), in which, having ex
plained that “the denial to this court of appellate jurisdic
tion” to consider an original writ of habeas corpus would
“greatly weaken the efficacy of the writ,” id., at 102–103,
we held that Congress would not be presumed to have
effected such denial absent an unmistakably clear state
ment to the contrary. See id., at 104–105; see also Felker
v. Turpin, 518 U. S. 651 (1996); Durousseau v. United
States, 6 Cranch 307, 314 (1810) (opinion for the Court by
Marshall, C. J.) (The “appellate powers of this court” are
not created by statute but are “given by the constitution”);
United States v. Klein, 13 Wall. 128 (1872). Cf. Ex parte
McCardle, 7 Wall. 506, 514 (1869) (holding that Congress
had validly foreclosed one avenue of appellate review
where its repeal of habeas jurisdiction, reproduced in the
margin,4 could not have been “a plainer instance of posi
——————
  4 “ ‘And be it further enacted, That so much of the act approved Febru

ary 5, 1867, entitled “An act to amend an act to establish the judicial
courts of the United States, approved September 24, 1789,” as author
ized an appeal from the judgment of the Circuit Court to the Supreme
Court of the United States, or the exercise of any such jurisdiction by
said Supreme Court, on appeals which have been, or may hereafter be
                    Cite as: 548 U. S. ____ (2006)                  11

                         Opinion of the Court

tive exception”). Hamdan also suggests that, if the Gov
ernment’s reading is correct, Congress has unconstitution
ally suspended the writ of habeas corpus.
   We find it unnecessary to reach either of these argu
ments. Ordinary principles of statutory construction suffice
to rebut the Government’s theory—at least insofar as this
case, which was pending at the time the DTA was enacted,
is concerned.
   The Government acknowledges that only paragraphs (2)
and (3) of subsection (e) are expressly made applicable to
pending cases, see §1005(h)(2), 119 Stat. 2743–2744, but
argues that the omission of paragraph (1) from the scope
of that express statement is of no moment. This is so, we
are told, because Congress’ failure to expressly reserve
federal courts’ jurisdiction over pending cases erects a
presumption against jurisdiction, and that presumption is
rebutted by neither the text nor the legislative history of
the DTA.
   The first part of this argument is not entirely without
support in our precedents. We have in the past “applied
intervening statutes conferring or ousting jurisdiction,
whether or not jurisdiction lay when the underlying con
duct occurred or when the suit was filed.” Landgraf v.
USI Film Products, 511 U. S. 244, 274 (1994) (citing
Bruner v. United States, 343 U. S. 112 (1952); Hallowell v.
Commons, 239 U. S. 506 (1916)); see Republic of Austria v.
Altmann, 541 U. S. 677, 693 (2004). But the “presump
tion” that these cases have applied is more accurately
viewed as the nonapplication of another presumption—
viz., the presumption against retroactivity—in certain
limited circumstances.5 If a statutory provision “would
——————
taken, be, and the same is hereby repealed.’ ” 7 Wall., at 508.
  5 See Hughes Aircraft Co. v. United States ex rel. Schumer, 520 U. S.

939, 951 (1997) (“The fact that courts often apply newly enacted juris
diction-allocating statutes to pending cases merely evidences certain
limited circumstances failing to meet the conditions for our generally
12                     HAMDAN v. RUMSFELD

                          Opinion of the Court

operate retroactively” as applied to cases pending at the
time the provision was enacted, then “our traditional
presumption teaches that it does not govern absent clear
congressional intent favoring such a result.” Landgraf,
511 U. S., at 280. We have explained, however, that,
unlike other intervening changes in the law, a jurisdiction-
conferring or jurisdiction-stripping statute usually “takes
away no substantive right but simply changes the tribunal
that is to hear the case.” Hallowell, 239 U. S., at 508. If
that is truly all the statute does, no retroactivity problem
arises because the change in the law does not “impair
rights a party possessed when he acted, increase a party’s
liability for past conduct, or impose new duties with re
spect to transactions already completed.” Landgraf, 511
U. S., at 280.6 And if a new rule has no retroactive effect,
the presumption against retroactivity will not prevent its
application to a case that was already pending when the
new rule was enacted.
   That does not mean, however, that all jurisdiction-
stripping provisions—or even all such provisions that
truly lack retroactive effect—must apply to cases pending
at the time of their enactment.7 “[N]ormal rules of con
——————
applicable presumption against retroactivity . . .”).
   6 Cf. Hughes Aircraft, 520 U. S., at 951 (“Statutes merely addressing

which court shall have jurisdiction to entertain a particular cause of
action can fairly be said merely to regulate the secondary conduct of
litigation and not the underlying primary conduct of the parties”
(emphasis in original)).
   7 In his insistence to the contrary, JUSTICE SCALIA reads too much into

Bruner v. United States, 343 U. S. 112 (1952), Hallowell v. Commons,
239 U. S. 506 (1916), and Insurance Co. v. Ritchie, 5 Wall. 541 (1867).
See post, at 2–4 (dissenting opinion). None of those cases says that the
absence of an express provision reserving jurisdiction over pending
cases trumps or renders irrelevant any other indications of congres
sional intent. Indeed, Bruner itself relied on such other indications–
including a negative inference drawn from the statutory text, cf. infra,
at 13–to support its conclusion that jurisdiction was not available. The
Court observed that (1) Congress had been put on notice by prior lower
                      Cite as: 548 U. S. ____ (2006)                     13

                           Opinion of the Court

struction,” including a contextual reading of the statutory
language, may dictate otherwise. Lindh v. Murphy, 521
U. S. 320, 326 (1997).8 A familiar principle of statutory
construction, relevant both in Lindh and here, is that a
negative inference may be drawn from the exclusion of
language from one statutory provision that is included in
other provisions of the same statute. See id., at 330; see
also, e.g., Russello v. United States, 464 U. S. 16, 23 (1983)
(“ ‘[W]here Congress includes particular language in one
section of a statute but omits it in another section of the
same Act, it is generally presumed that Congress acts
intentionally and purposely in the disparate inclusion or
exclusion’ ”). The Court in Lindh relied on this reasoning
to conclude that certain limitations on the availability of
habeas relief imposed by AEDPA applied only to cases
filed after that statute’s effective date. Congress’ failure to
identify the temporal reach of those limitations, which
governed noncapital cases, stood in contrast to its express
command in the same legislation that new rules governing
habeas petitions in capital cases “apply to cases pending
on or after the date of enactment.” §107(c), 110 Stat. 1226;
see Lindh, 521 U. S., at 329–330. That contrast, combined
with the fact that the amendments at issue “affect[ed]
substantive entitlement to relief,” id., at 327, warranted
——————
court cases addressing the Tucker Act that it ought to specifically
reserve jurisdiction over pending cases, see 343 U. S., at 115, and (2) in
contrast to the congressional silence concerning reservation of jurisdic
tion, reservation had been made of “ ‘any rights or liabilities’ existing at
the effective date of the Act” repealed by another provision of the Act,
ibid., n. 7.
   8 The question in Lindh was whether new limitations on the avail

ability of habeas relief imposed by the Antiterrorism and Effective
Death Penalty Act of 1996 (AEDPA), 110 Stat. 1214, applied to habeas
actions pending on the date of AEDPA’s enactment. We held that they
did not. At the outset, we rejected the State’s argument that, in the
absence of a clear congressional statement to the contrary, a “proce
dural” rule must apply to pending cases. 521 U. S., at 326.
14                     HAMDAN v. RUMSFELD

                          Opinion of the Court

drawing a negative inference.
  A like inference follows a fortiori from Lindh in this
case. “If . . . Congress was reasonably concerned to ensure
that [§§1005(e)(2) and (3)] be applied to pending cases, it
should have been just as concerned about [§1005(e)(1)],
unless it had the different intent that the latter [section]
not be applied to the general run of pending cases.” Id., at
329. If anything, the evidence of deliberate omission is
stronger here than it was in Lindh. In Lindh, the provi
sions to be contrasted had been drafted separately but
were later “joined together and . . . considered simultane
ously when the language raising the implication was
inserted.” Id., at 330. We observed that Congress’ tandem
review and approval of the two sets of provisions strength
ened the presumption that the relevant omission was
deliberate. Id., at 331; see also Field v. Mans, 516 U. S.
59, 75 (1995) (“The more apparently deliberate the con
trast, the stronger the inference, as applied, for example,
to contrasting statutory sections originally enacted simul
taneously in relevant respects”). Here, Congress not only
considered the respective temporal reaches of paragraphs
(1), (2), and (3) of subsection (e) together at every stage,
but omitted paragraph (1) from its directive that para
graphs (2) and (3) apply to pending cases only after having
rejected earlier proposed versions of the statute that would
have included what is now paragraph (1) within the scope
of that directive. Compare DTA §1005(h)(2), 119 Stat.
2743–2744, with 151 Cong. Rec. S12655 (Nov. 10, 2005) (S.
Amdt. 2515); see id., at S14257–S14258 (Dec. 21, 2005)
(discussing similar language proposed in both the House
and the Senate).9 Congress’ rejection of the very language
——————
   9 That paragraph (1), along with paragraphs (2) and (3), is to “take

effect on the date of enactment,” DTA §1005(h)(1), 119 Stat. 2743, is not
dispositive; “a ‘statement that a statute will become effective on a
certain date does not even arguably suggest that it has any application
to conduct that occurred at an earlier date.’ ” INS v. St. Cyr, 533 U. S.
                     Cite as: 548 U. S. ____ (2006)                    15

                          Opinion of the Court

that would have achieved the result the Government urges
here weighs heavily against the Government’s interpreta
tion. See Doe v. Chao, 540 U. S. 614, 621–623 (2004).10
——————
289, 317 (2001) (quoting Landgraf v. USI Film Products, 511 U. S. 244,
257 (1994)). Certainly, the “effective date” provision cannot bear the
weight JUSTICE SCALIA would place on it. See post, at 5, and n. 1.
Congress deemed that provision insufficient, standing alone, to render
subsections (e)(2) and (e)(3) applicable to pending cases; hence its
adoption of subsection (h)(2). JUSTICE SCALIA seeks to avoid reducing
subsection (h)(2) to a mere redundancy—a consequence he seems to
acknowledge must otherwise follow from his interpretation—by specu
lating that Congress had special reasons, not also relevant to subsec
tion (e)(1), to worry that subsections (e)(2) and (e)(3) would be ruled
inapplicable to pending cases. As we explain infra, at 17, and n. 12,
that attempt fails.
   10 We note that statements made by Senators preceding passage of

the Act lend further support to what the text of the DTA and its draft
ing history already make plain. Senator Levin, one of the sponsors of
the final bill, objected to earlier versions of the Act’s “effective date”
provision that would have made subsection (e)(1) applicable to pending
cases. See, e.g., 151 Cong. Rec. S12667 (Nov. 10, 2005) (amendment
proposed by Sen. Graham that would have rendered what is now
subsection (e)(1) applicable to “any application or other action that is
pending on or after the date of the enactment of this Act”). Senator
Levin urged adoption of an alternative amendment that “would apply
only to new habeas cases filed after the date of enactment.” Id., at
S12802 (Nov. 15, 2005). That alternative amendment became the text
of subsection (h)(2). (In light of the extensive discussion of the DTA’s
effect on pending cases prior to passage of the Act, see, e.g., id., at
S12664 (Nov. 10, 2005); id., at S12755 (Nov. 14, 2005); id., at S12799–
S12802 (Nov. 15, 2005); id., at S14245, S14252–S14253, S14257–
S14258, S14274–S14275 (Dec. 21, 2005), it cannot be said that the
changes to subsection (h)(2) were inconsequential. Cf. post, at 14
(SCALIA, J., dissenting).)
   While statements attributed to the final bill’s two other sponsors,
Senators Graham and Kyl, arguably contradict Senator Levin’s conten
tion that the final version of the Act preserved jurisdiction over pending
habeas cases, see 151 Cong. Rec. S14263–S14264 (Dec. 21, 2005), those
statements appear to have been inserted into the Congressional Record
after the Senate debate. See Reply Brief for Petitioner 5, n. 6; see also
151 Cong. Rec. S14260 (statement of Sen. Kyl) (“I would like to say a
few words about the now-completed National Defense Authorization Act
16                     HAMDAN v. RUMSFELD

                          Opinion of the Court

   The Government nonetheless offers two reasons why, in
its view, no negative inference may be drawn in favor of
jurisdiction. First, it asserts that Lindh is inapposite
because “Section 1005(e)(1) and (h)(1) remove jurisdiction,
while Section 1005(e)(2), (3) and (h)(2) create an exclusive
review mechanism and define the nature of that review.”
Reply Brief in Support of Respondents’ Motion to Dismiss
4. Because the provisions being contrasted “address
wholly distinct subject matters,” Martin v. Hadix, 527
U. S. 343, 356 (1999), the Government argues, Congress’
different treatment of them is of no significance.
   This argument must fail because it rests on a false dis
tinction between the “jurisdictional” nature of subsection
(e)(1) and the “procedural” character of subsections (e)(2)
and (e)(3). In truth, all three provisions govern jurisdic
tion over detainees’ claims; subsection (e)(1) addresses
jurisdiction in habeas cases and other actions “relating to
any aspect of the detention,” while subsections (e)(2) and
(3) vest exclusive,11 but limited, jurisdiction in the Court of
——————
for fiscal year 2006” (emphasis added)). All statements made during
the debate itself support Senator Levin’s understanding that the final
text of the DTA would not render subsection (e)(1) applicable to pend
ing cases. See, e.g., id., at S14245, S14252–S14253, S14274–S14275
(Dec. 21, 2005). The statements that JUSTICE SCALIA cites as evidence
to the contrary construe subsection (e)(3) to strip this Court of jurisdic
tion, see post, at 12, n. 4 (dissenting opinion) (quoting 151 Cong. Rec.
S12796 (Nov. 15, 2005) (statement of Sen. Specter))—a construction
that the Government has expressly disavowed in this litigation, see n.
11, infra. The inapposite November 14, 2005, statement of Senator
Graham, which JUSTICE SCALIA cites as evidence of that Senator’s
“assumption that pending cases are covered,” post, at 12, and n. 3
(citing 151 Cong. Rec. S12756 (Nov. 14, 2005)), follows directly after the
uncontradicted statement of his co-sponsor, Senator Levin, assuring
members of the Senate that “the amendment will not strip the courts of
jurisdiction over [pending] cases.” Id., at S12755.
   11 The District of Columbia Circuit’s jurisdiction, while “exclusive” in

one sense, would not bar this Court’s review on appeal from a decision
under the DTA. See Reply Brief in Support of Respondents’ Motion to
                     Cite as: 548 U. S. ____ (2006)                    17

                          Opinion of the Court

Appeals for the District of Columbia Circuit to review
“final decision[s]” of CSRTs and military commissions.
   That subsection (e)(1) strips jurisdiction while subsec
tions (e)(2) and (e)(3) restore it in limited form is hardly a
distinction upon which a negative inference must founder.
JUSTICE SCALIA, in arguing to the contrary, maintains
that Congress had “ample reason” to provide explicitly for
application of subsections (e)(2) and (e)(3) to pending cases
because “jurisdiction-stripping” provisions like subsection
(e)(1) have been treated differently under our retroactivity
jurisprudence than “jurisdiction-conferring” ones like
subsections (e)(2) and (e)(3). Post, at 8 (dissenting opin
ion); see also Reply Brief in Support of Respondents’ Mo
tion to Dismiss 5–6. That theory is insupportable. As
suming arguendo that subsections (e)(2) and (e)(3) “confer
new jurisdiction (in the D. C. Circuit) where there was
none before,” post, at 8 (emphasis in original); but see
Rasul v. Bush, 542 U. S. 466 (2004), and that our prece
dents can be read to “strongly indicat[e]” that jurisdiction-
creating statutes raise special retroactivity concerns not
also raised by jurisdiction-stripping statutes, post, at 8,12
subsections (e)(2) and (e)(3) “confer” jurisdiction in a man

——————
Dismiss 16–17, n. 12 (“While the DTA does not expressly call for
Supreme Court review of the District of Columbia Circuit’s decisions,
Section 1005(e)(2) and (3) . . . do not remove this Court’s jurisdiction
over such decisions under 28 U. S. C. §1254(1)”).
   12 This assertion is itself highly questionable. The cases that JUSTICE

SCALIA cites to support his distinction are Republic of Austria v.
Altmann, 541 U. S. 677 (2004), and Hughes Aircraft Co. v. United
States ex rel. Schumer, 520 U. S. 939 (1997). See post, at 8. While the
Court in both of those cases recognized that statutes “creating” jurisdic
tion may have retroactive effect if they affect “substantive” rights, see
Altmann, 541 U. S., at 695, and n. 15; Hughes Aircraft, 520 U. S., at
951, we have applied the same analysis to statutes that have jurisdic
tion-stripping effect, see Lindh v. Murphy, 521 U. S. 320, 327–328
(1997); id., at 342–343 (Rehnquist, C. J., dissenting) (construing
AEDPA’s amendments as “ousting jurisdiction”).
18                     HAMDAN v. RUMSFELD

                          Opinion of the Court

ner that cannot conceivably give rise to retroactivity ques
tions under our precedents. The provisions impose no
additional liability or obligation on any private party or
even on the United States, unless one counts the burden of
litigating an appeal—a burden not a single one of our
cases suggests triggers retroactivity concerns.13 Moreover,
it strains credulity to suggest that the desire to reinforce
the application of subsections (e)(2) and (e)(3) to pending
cases drove Congress to exclude subsection (e)(1) from
§1005(h)(2).
   The Government’s second objection is that applying
subsections (e)(2) and (e)(3) but not (e)(1) to pending cases
“produces an absurd result” because it grants (albeit only
temporarily) dual jurisdiction over detainees’ cases in
circumstances where the statute plainly envisions that the
District of Columbia Circuit will have “exclusive” and
immediate jurisdiction over such cases. Reply Brief in
Support of Respondents’ Motion to Dismiss 7. But the
premise here is faulty; subsections (e)(2) and (e)(3) grant
jurisdiction only over actions to “determine the validity of
any final decision” of a CSRT or commission. Because
Hamdan, at least, is not contesting any “final decision” of
a CSRT or military commission, his action does not fall
within the scope of subsection (e)(2) or (e)(3). There is,
then, no absurdity.14
——————
  13 See Landgraf, 511 U. S., at 271, n. 25 (observing that “the great

majority of our decisions relying upon the antiretroactivity presumption
have involved intervening statutes burdening private parties,” though
“we have applied the presumption in cases involving new monetary
obligations that fell only on the government” (emphasis added)); see
also Altmann, 541 U. S., at 728–729 (KENNEDY, J., dissenting) (explain
ing that if retroactivity concerns do not arise when a new monetary
obligation is imposed on the United States it is because “Congress, by
virtue of authoring the legislation, is itself fully capable of protecting
the Federal Government from having its rights degraded by retroactive
laws”).
  14 There may be habeas cases that were pending in the lower courts at
                   Cite as: 548 U. S. ____ (2006)                19

                        Opinion of the Court

   The Government’s more general suggestion that Con
gress can have had no good reason for preserving habeas
jurisdiction over cases that had been brought by detainees
prior to enactment of the DTA not only is belied by the
legislative history, see n. 10, supra, but is otherwise with
out merit. There is nothing absurd about a scheme under
which pending habeas actions—particularly those, like
this one, that challenge the very legitimacy of the tribu
nals whose judgments Congress would like to have re
viewed—are preserved, and more routine challenges to
final decisions rendered by those tribunals are carefully
channeled to a particular court and through a particular
lens of review.
   Finally, we cannot leave unaddressed JUSTICE SCALIA’s
contentions that the “meaning of §1005(e)(1) is entirely
clear,” post, at 6, and that “the plain import of a statute
repealing jurisdiction is to eliminate the power to consider
and render judgment—in an already pending case no less
than in a case yet to be filed,” post, at 3 (emphasis in
original). Only by treating the Bruner rule as an inflexible
trump (a thing it has never been, see n. 7, supra) and
ignoring both the rest of §1005’s text and its drafting
history can one conclude as much. Congress here ex
pressly provided that subsections (e)(2) and (e)(3) applied
to pending cases. It chose not to so provide—after having
been presented with the option—for subsection (e)(1). The
omission is an integral part of the statutory scheme that
muddies whatever “plain meaning” may be discerned from
blinkered study of subsection (e)(1) alone. The dissent’s
speculation about what Congress might have intended by
the omission not only is counterfactual, cf. n. 10, supra

——————
the time the DTA was enacted that do qualify as challenges to “final
decision[s]” within the meaning of subsection (e)(2) or (e)(3). We
express no view about whether the DTA would require transfer of such
an action to the District of Columbia Circuit.
20                    HAMDAN v. RUMSFELD

                         Opinion of the Court

(recounting legislative history), but rests on both a mis
construction of the DTA and an erroneous view our prece
dents, see supra, at 17, and n. 12.
  For these reasons, we deny the Government’s motion to
dismiss.15
                              III
  Relying on our decision in Councilman, 420 U. S. 738,
the Government argues that, even if we have statutory
jurisdiction, we should apply the “judge-made rule that
civilian courts should await the final outcome of on-going
military proceedings before entertaining an attack on
those proceedings.” Brief for Respondents 12. Like the
District Court and the Court of Appeals before us, we
reject this argument.
  In Councilman, an army officer on active duty was
referred to a court-martial for trial on charges that he
violated the UCMJ by selling, transferring, and possessing
marijuana. 420 U. S., at 739–740. Objecting that the
alleged offenses were not “ ‘service connected,’ ” id., at 740,
the officer filed suit in Federal District Court to enjoin the
proceedings. He neither questioned the lawfulness of
courts-martial or their procedures nor disputed that, as a
serviceman, he was subject to court-martial jurisdiction.
His sole argument was that the subject matter of his case
did not fall within the scope of court-martial authority.
See id., at 741, 759. The District Court granted his re
quest for injunctive relief, and the Court of Appeals
——————
  15 Because we conclude that §1005(e)(1) does not strip federal courts’

jurisdiction over cases pending on the date of the DTA’s enactment, we
do not decide whether, if it were otherwise, this Court would nonethe
less retain jurisdiction to hear Hamdan’s appeal. Cf. supra, at 10. Nor
do we decide the manner in which the canon of constitutional avoidance
should affect subsequent interpretation of the DTA. See, e.g., St. Cyr,
533 U. S., at 300 (a construction of a statute “that would entirely
preclude review of a pure question of law by any court would give rise
to substantial constitutional questions”).
                     Cite as: 548 U. S. ____ (2006)                  21

                         Opinion of the Court

affirmed.
   We granted certiorari and reversed. Id., at 761. We did
not reach the merits of whether the marijuana charges
were sufficiently “service connected” to place them within
the subject-matter jurisdiction of a court-martial. Instead,
we concluded that, as a matter of comity, federal courts
should normally abstain from intervening in pending
court-martial proceedings against members of the Armed
Forces,16 and further that there was nothing in the par
ticular circumstances of the officer’s case to displace that
general rule. See id., at 740, 758.
   Councilman identifies two considerations of comity that
together favor abstention pending completion of ongoing
court-martial proceedings against service personnel. See
New v. Cohen, 129 F. 3d 639, 643 (CADC 1997); see also
415 F. 3d, at 36–37 (discussing Councilman and New).
First, military discipline and, therefore, the efficient op
eration of the Armed Forces are best served if the military
justice system acts without regular interference from
civilian courts. See Councilman, 420 U. S., at 752. Sec
ond, federal courts should respect the balance that Con
gress struck between military preparedness and fairness
to individual service members when it created “an inte
grated system of military courts and review procedures, a
——————
  16 Councilman   distinguished service personnel from civilians, whose
challenges to ongoing military proceedings are cognizable in federal
court. See, e.g., United States ex rel. Toth v. Quarles, 350 U. S. 11
(1955). As we explained in Councilman, abstention is not appropriate
in cases in which individuals raise “ ‘substantial arguments denying the
right of the military to try them at all,’ ” and in which the legal chal
lenge “turn[s] on the status of the persons as to whom the military
asserted its power.” 420 U. S., at 759 (quoting Noyd v. Bond, 395 U. S.
683, 696, n. 8 (1969)). In other words, we do not apply Councilman
abstention when there is a substantial question whether a military
tribunal has personal jurisdiction over the defendant. Because we
conclude that abstention is inappropriate for a more basic reason, we
need not consider whether the jurisdictional exception recognized in
Councilman applies here.
22                     HAMDAN v. RUMSFELD

                          Opinion of the Court

critical element of which is the Court of Military Appeals,
consisting of civilian judges ‘completely removed from all
military influence or persuasion . . . .’ ” Id., at 758 (quot
ing H. R. Rep. No. 491, 81st Cong., 1st Sess., p. 7 (1949)).
Just as abstention in the face of ongoing state criminal
proceedings is justified by our expectation that state
courts will enforce federal rights, so abstention in the face
of ongoing court-martial proceedings is justified by our
expectation that the military court system established by
Congress—with its substantial procedural protections and
provision for appellate review by independent civilian
judges—“will vindicate servicemen’s constitutional rights,”
420 U. S., at 758. See id., at 755–758.17
  The same cannot be said here; indeed, neither of the
comity considerations identified in Councilman weighs in
favor of abstention in this case. First, Hamdan is not a
member of our Nation’s Armed Forces, so concerns about
military discipline do not apply. Second, the tribunal
convened to try Hamdan is not part of the integrated
system of military courts, complete with independent
review panels, that Congress has established. Unlike the
officer in Councilman, Hamdan has no right to appeal any
conviction to the civilian judges of the Court of Military
Appeals (now called the United States Court of Appeals
for the Armed Forces, see Pub. L. 103–337, 108 Stat.
2831). Instead, under Dept. of Defense Military Commis
——————
  17 See also Noyd, 395 U. S., at 694–696 (noting that the Court of Mili
tary Appeals consisted of “disinterested civilian judges,” and concluding
that there was no reason for the Court to address an Air Force Captain’s
argument that he was entitled to remain free from confinement pending
appeal of his conviction by court-martial “when the highest military
court stands ready to consider petitioner’s arguments”). Cf. Parisi v.
Davidson, 405 U. S. 34, 41–43 (1972) (“Under accepted principles of
comity, the court should stay its hand only if the relief the petitioner
seeks . . . would also be available to him with reasonable promptness
and certainty through the machinery of the military judicial system in
its processing of the court-martial charge”).
                    Cite as: 548 U. S. ____ (2006)                  23

                         Opinion of the Court

sion Order No. 1 (Commission Order No. 1), which was
issued by the President on March 21, 2002, and amended
most recently on August 31, 2005, and which governs the
procedures for Hamdan’s commission, any conviction
would be reviewed by a panel consisting of three military
officers designated by the Secretary of Defense. Commis
sion Order No. 1 §6(H)(4). Commission Order No. 1 pro
vides that appeal of a review panel’s decision may be had
only to the Secretary of Defense himself, §6(H)(5), and
then, finally, to the President, §6(H)(6).18
   We have no doubt that the various individuals assigned
review power under Commission Order No. 1 would strive
to act impartially and ensure that Hamdan receive all
protections to which he is entitled. Nonetheless, these
review bodies clearly lack the structural insulation from
military influence that characterizes the Court of Appeals
for the Armed Forces, and thus bear insufficient concep
tual similarity to state courts to warrant invocation of
abstention principles.19
   In sum, neither of the two comity considerations under
lying our decision to abstain in Councilman applies to the
circumstances of this case. Instead, this Court’s decision
in Quirin is the most relevant precedent. In Quirin, seven
German saboteurs were captured upon arrival by subma
rine in New York and Florida. 317 U. S., at 21. The Presi
dent convened a military commission to try the saboteurs,
who then filed habeas corpus petitions in the United

——————
  18 If he chooses, the President may delegate this ultimate decision-

making authority to the Secretary of Defense. See §6(H)(6).
  19 JUSTICE SCALIA chides us for failing to include the District of Co

lumbia Circuit’s review powers under the DTA in our description of the
review mechanism erected by Commission Order No. 1. See post, at 22.
Whether or not the limited review permitted under the DTA may be
treated as akin to the plenary review exercised by the Court of Appeals
for the Armed Forces, petitioner here is not afforded a right to such
review. See infra, at 52; §1005(e)(3), 119 Stat. 2743.
24                     HAMDAN v. RUMSFELD

                          Opinion of the Court

States District Court for the District of Columbia challeng
ing their trial by commission. We granted the saboteurs’
petition for certiorari to the Court of Appeals before judg
ment. See id., at 19. Far from abstaining pending the
conclusion of military proceedings, which were ongoing,
we convened a special Term to hear the case and expedited
our review. That course of action was warranted, we
explained, “[i]n view of the public importance of the ques
tions raised by [the cases] and of the duty which rests on
the courts, in time of war as well as in time of peace, to
preserve unimpaired the constitutional safeguards of civil
liberty, and because in our opinion the public interest
required that we consider and decide those questions
without any avoidable delay.” Ibid.
   As the Court of Appeals here recognized, Quirin “pro
vides a compelling historical precedent for the power of
civilian courts to entertain challenges that seek to inter
rupt the processes of military commissions.” 415 F. 3d, at
36.20 The circumstances of this case, like those in Quirin,
——————
   20 Having correctly declined to abstain from addressing Hamdan’s

challenge to the lawfulness of the military commission convened to try
him, the Court of Appeals suggested that Councilman abstention
nonetheless applied to bar its consideration of one of Hamdan’s argu
ments—namely, that his commission violated Article 3 of the Third
Geneva Convention, 6 U. S. T. 3316, 3318. See Part VI, infra. Al
though the Court of Appeals rejected the Article 3 argument on the
merits, it also stated that, because the challenge was not “jurisdic
tional,” it did not fall within the exception that Schlesinger v. Council
man, 420 U. S. 738 (1975), recognized for defendants who raise sub
stantial arguments that a military tribunal lacks personal jurisdiction
over them. See 415 F. 3d, at 42.
   In reaching this conclusion, the Court of Appeals conflated two
distinct inquiries: (1) whether Hamdan has raised a substantial argu
ment that the military commission lacks authority to try him; and,
more fundamentally, (2) whether the comity considerations underlying
Councilman apply to trigger the abstention principle in the first place.
As the Court of Appeals acknowledged at the beginning of its opinion,
the first question warrants consideration only if the answer to the
                     Cite as: 548 U. S. ____ (2006)                  25

                         Opinion of the Court

simply do not implicate the “obligations of comity” that,
under appropriate circumstances, justify abstention.
Quackenbush v. Allstate Ins. Co., 517 U. S. 706, 733 (1996)
(KENNEDY, J., concurring).
   Finally, the Government has identified no other “impor
tant countervailing interest” that would permit federal
courts to depart from their general “duty to exercise the
jurisdiction that is conferred upon them by Congress.” Id.,
at 716 (majority opinion). To the contrary, Hamdan and
the Government both have a compelling interest in know
ing in advance whether Hamdan may be tried by a mili
tary commission that arguably is without any basis in law
and operates free from many of the procedural rules pre
scribed by Congress for courts-martial—rules intended to
safeguard the accused and ensure the reliability of any
conviction. While we certainly do not foreclose the possi
bility that abstention may be appropriate in some cases
seeking review of ongoing military commission proceed
ings (such as military commissions convened on the battle
field), the foregoing discussion makes clear that, under our
precedent, abstention is not justified here. We therefore
proceed to consider the merits of Hamdan’s challenge.
                           IV
  The military commission, a tribunal neither mentioned
in the Constitution nor created by statute, was born of
military necessity. See W. Winthrop, Military Law and
Precedents 831 (rev. 2d ed. 1920) (hereinafter Winthrop).
——————
second is yes. See 415 F. 3d, at 36–37. Since, as the Court of Appeals
properly concluded, the answer to the second question is in fact no,
there is no need to consider any exception.
   At any rate, it appears that the exception would apply here. As
discussed in Part VI, infra, Hamdan raises a substantial argument
that, because the military commission that has been convened to try
him is not a “ ‘regularly constituted court’ ” under the Geneva Conven
tions, it is ultra vires and thus lacks jurisdiction over him. Brief for
Petitioner 5.
26                 HAMDAN v. RUMSFELD

                     Opinion of the Court

Though foreshadowed in some respects by earlier tribu
nals like the Board of General Officers that General Wash
ington convened to try British Major John André for spy
ing during the Revolutionary War, the commission “as
such” was inaugurated in 1847. Id., at 832; G. Davis, A
Treatise on the Military Law of the United States 308 (2d
ed. 1909) (hereinafter Davis). As commander of occupied
Mexican territory, and having available to him no other
tribunal, General Winfield Scott that year ordered the
establishment of both “ ‘military commissions’ ” to try
ordinary crimes committed in the occupied territory and a
“council of war” to try offenses against the law of war.
Winthrop 832 (emphases in original).
   When the exigencies of war next gave rise to a need for
use of military commissions, during the Civil War, the
dual system favored by General Scott was not adopted.
Instead, a single tribunal often took jurisdiction over
ordinary crimes, war crimes, and breaches of military
orders alike. As further discussed below, each aspect of
that seemingly broad jurisdiction was in fact supported by
a separate military exigency. Generally, though, the need
for military commissions during this period—as during the
Mexican War—was driven largely by the then very limited
jurisdiction of courts-martial: “The occasion for the mili
tary commission arises principally from the fact that the
jurisdiction of the court-martial proper, in our law, is
restricted by statute almost exclusively to members of the
military force and to certain specific offences defined in a
written code.” Id., at 831 (emphasis in original).
   Exigency alone, of course, will not justify the establish
ment and use of penal tribunals not contemplated by
Article I, §8 and Article III, §1 of the Constitution unless
some other part of that document authorizes a response to
the felt need. See Ex parte Milligan, 4 Wall. 2, 121 (1866)
(“Certainly no part of the judicial power of the country was
conferred on [military commissions]”); Ex parte Val
                     Cite as: 548 U. S. ____ (2006)                  27

                         Opinion of the Court

landigham, 1 Wall. 243, 251 (1864); see also Quirin, 317
U. S., at 25 (“Congress and the President, like the courts,
possess no power not derived from the Constitution”). And
that authority, if it exists, can derive only from the powers
granted jointly to the President and Congress in time of
war. See id., at 26–29; In re Yamashita, 327 U. S. 1, 11
(1946).
   The Constitution makes the President the “Commander
in Chief” of the Armed Forces, Art. II, §2, cl. 1, but vests in
Congress the powers to “declare War . . . and make Rules
concerning Captures on Land and Water,” Art. I, §8, cl. 11,
to “raise and support Armies,” id., cl. 12, to “define and
punish . . . Offences against the Law of Nations,” id., cl.
10, and “To make Rules for the Government and Regula
tion of the land and naval Forces,” id., cl. 14. The inter
play between these powers was described by Chief Justice
Chase in the seminal case of Ex parte Milligan:
     “The power to make the necessary laws is in Con
     gress; the power to execute in the President. Both
     powers imply many subordinate and auxiliary powers.
     Each includes all authorities essential to its due exer
     cise. But neither can the President, in war more than
     in peace, intrude upon the proper authority of Con
     gress, nor Congress upon the proper authority of the
     President. . . . Congress cannot direct the conduct of
     campaigns, nor can the President, or any commander
     under him, without the sanction of Congress, institute
     tribunals for the trial and punishment of offences, ei
     ther of soldiers or civilians, unless in cases of a con
     trolling necessity, which justifies what it compels, or
     at least insures acts of indemnity from the justice of
     the legislature.” 4 Wall., at 139–140.21

——————
  21 See also Winthrop 831 (“[I]n general, it is those provisions of the

Constitution which empower Congress to ‘declare war’ and ‘raise
28                     HAMDAN v. RUMSFELD

                          Opinion of the Court

   Whether Chief Justice Chase was correct in suggesting
that the President may constitutionally convene military
commissions “without the sanction of Congress” in cases of
“controlling necessity” is a question this Court has not
answered definitively, and need not answer today. For we
held in Quirin that Congress had, through Article of War
15, sanctioned the use of military commissions in such
circumstances. 317 U. S., at 28 (“By the Articles of War,
and especially Article 15, Congress has explicitly provided,
so far as it may constitutionally do so, that military tribu
nals shall have jurisdiction to try offenders or offenses
against the law of war in appropriate cases”). Article 21 of
the UCMJ, the language of which is substantially identical
to the old Article 15 and was preserved by Congress after
World War II,22 reads as follows:
     “Jurisdiction of courts-martial not exclusive.
     “The provisions of this code conferring jurisdiction
     upon courts-martial shall not be construed as depriv
     ing military commissions, provost courts, or other
     military tribunals of concurrent jurisdiction in respect
     of offenders or offenses that by statute or by the law of
     war may be tried by such military commissions, pro
     vost courts, or other military tribunals.” 64 Stat. 115.
  We have no occasion to revisit Quirin’s controversial
characterization of Article of War 15 as congressional
authorization for military commissions. Cf. Brief for Legal
——————
armies,’ and which, in authorizing the initiation of war, authorize the
employment of all necessary and proper agencies for its due prosecu
tion, from which this tribunal derives its original sanction” (emphasis
in original)).
   22 Article 15 was first adopted as part of the Articles of War in 1916.

See Act of Aug. 29, 1916, ch. 418, §3, Art. 15, 39 Stat. 652. When the
Articles of War were codified and re-enacted as the UCMJ in 1950,
Congress determined to retain Article 15 because it had been “con
strued by the Supreme Court (Ex Parte Quirin, 317 U. S. 1 (1942)).”
S. Rep. No. 486, 81st Cong., 1st Sess., 13 (1949).
                    Cite as: 548 U. S. ____ (2006)                 29

                        Opinion of the Court

Scholars and Historians as Amici Curiae 12–15. Contrary
to the Government’s assertion, however, even Quirin did
not view the authorization as a sweeping mandate for the
President to “invoke military commissions when he deems
them necessary.” Brief for Respondents 17. Rather, the
Quirin Court recognized that Congress had simply pre
served what power, under the Constitution and the com
mon law of war, the President had had before 1916 to
convene military commissions—with the express condition
that the President and those under his command comply
with the law of war. See 317 U. S., at 28–29.23 That much
is evidenced by the Court’s inquiry, following its conclu
sion that Congress had authorized military commissions,
into whether the law of war had indeed been complied
with in that case. See ibid.
   The Government would have us dispense with the in
quiry that the Quirin Court undertook and find in either
the AUMF or the DTA specific, overriding authorization
for the very commission that has been convened to try
Hamdan. Neither of these congressional Acts, however,
expands the President’s authority to convene military
commissions. First, while we assume that the AUMF
activated the President’s war powers, see Hamdi v. Rums
feld, 542 U. S. 507 (2004) (plurality opinion), and that
those powers include the authority to convene military
commissions in appropriate circumstances, see id., at 518;
Quirin, 317 U. S., at 28–29; see also Yamashita, 327 U. S.,
at 11, there is nothing in the text or legislative history of
the AUMF even hinting that Congress intended to expand
or alter the authorization set forth in Article 21 of the
——————
  23 Whether or not the President has independent power, absent con

gressional authorization, to convene military commissions, he may not
disregard limitations that Congress has, in proper exercise of its own
war powers, placed on his powers. See Youngstown Sheet & Tube Co. v.
Sawyer, 343 U. S. 579, 637 (1952) (Jackson, J., concurring). The
Government does not argue otherwise.
30                    HAMDAN v. RUMSFELD

                         Opinion of the Court

UCMJ. Cf. Yerger, 8 Wall., at 105 (“Repeals by implica
tion are not favored”).24
   Likewise, the DTA cannot be read to authorize this
commission. Although the DTA, unlike either Article 21
or the AUMF, was enacted after the President had con
vened Hamdan’s commission, it contains no language
authorizing that tribunal or any other at Guantanamo
Bay. The DTA obviously “recognize[s]” the existence of the
Guantanamo Bay commissions in the weakest sense, Brief
for Respondents 15, because it references some of the
military orders governing them and creates limited judi
cial review of their “final decision[s],” DTA §1005(e)(3),
119 Stat. 2743. But the statute also pointedly reserves
judgment on whether “the Constitution and laws of the
United States are applicable” in reviewing such decisions
and whether, if they are, the “standards and procedures”
used to try Hamdan and other detainees actually violate
the “Constitution and laws.” Ibid.
   Together, the UCMJ, the AUMF, and the DTA at most
acknowledge a general Presidential authority to convene
military commissions in circumstances where justified
under the “Constitution and laws,” including the law of
war. Absent a more specific congressional authorization,
the task of this Court is, as it was in Quirin, to decide
whether Hamdan’s military commission is so justified. It
is to that inquiry we now turn.


——————
  24 On this point, it is noteworthy that the Court in Ex parte Quirin,

317 U. S. 1 (1942), looked beyond Congress’ declaration of war and
accompanying authorization for use of force during World War II, and
relied instead on Article of War 15 to find that Congress had authorized
the use of military commissions in some circumstances. See id., at 26–
29. JUSTICE THOMAS’ assertion that we commit “error” in reading
Article 21 of the UCMJ to place limitations upon the President’s use of
military commissions, see post, at 5 (dissenting opinion), ignores the
reasoning in Quirin.
                      Cite as: 548 U. S. ____ (2006)                      31

                          Opinion of STEVENS, J.

                               V
  The common law governing military commissions may
be gleaned from past practice and what sparse legal prece
dent exists. Commissions historically have been used in
three situations. See Bradley & Goldsmith, Congressional
Authorization and the War on Terrorism, 118 Harv.
L. Rev. 2048, 2132–2133 (2005); Winthrop 831–846; Hear
ings on H. R. 2498 before the Subcommittee of the House
Committee on Armed Services, 81st Cong., 1st Sess., 975
(1949). First, they have substituted for civilian courts at
times and in places where martial law has been declared.
Their use in these circumstances has raised constitutional
questions, see Duncan v. Kahanamoku, 327 U. S. 304
(1946); Milligan, 4 Wall., at 121–122, but is well recog
nized.25 See Winthrop 822, 836–839. Second, commis
sions have been established to try civilians “as part of a
temporary military government over occupied enemy
territory or territory regained from an enemy where civil
ian government cannot and does not function.” Duncan,
327 U. S., at 314; see Milligan, 4 Wall., at 141–142 (Chase,
C. J., concurring in judgment) (distinguishing “MARTIAL
LAW PROPER” from “MILITARY GOVERNMENT” in occupied
territory). Illustrative of this second kind of commission is
——————
  25 The    justification for, and limitations on, these commissions were
summarized in Milligan:
   “If, in foreign invasion or civil war, the courts are actually closed, and
it is impossible to administer criminal justice according to law, then, on
the theatre of active military operations, where war really prevails,
there is a necessity to furnish a substitute for the civil authority, thus
overthrown, to preserve the safety of the army and society; and as no
power is left but the military, it is allowed to govern by martial rule
until the laws can have their free course. As necessity creates the rule,
so it limits its duration; for, if this government is continued after the
courts are reinstated, it is a gross usurpation of power. Martial rule
can never exist where the courts are open, and in the proper and
unobstructed exercise of their jurisdiction. It is also confined to the
locality of actual war.” 4 Wall., at 127 (emphases in original).
32                    HAMDAN v. RUMSFELD

                        Opinion of STEVENS, J.

the one that was established, with jurisdiction to apply the
German Criminal Code, in occupied Germany following
the end of World War II. See Madsen v. Kinsella, 343
U. S. 341, 356 (1952).26
  The third type of commission, convened as an “incident
to the conduct of war” when there is a need “to seize and
subject to disciplinary measures those enemies who in
their attempt to thwart or impede our military effort have
violated the law of war,” Quirin, 317 U. S., at 28–29, has
been described as “utterly different” from the other two.
Bickers, Military Commissions are Constitutionally Sound:
A Response to Professors Katyal and Tribe, 34 Tex. Tech.
L. Rev. 899, 902 (2002–2003).27 Not only is its jurisdiction
limited to offenses cognizable during time of war, but its
role is primarily a factfinding one—to determine, typically
on the battlefield itself, whether the defendant has vio
lated the law of war. The last time the U. S. Armed Forces


——————
   26 The limitations on these occupied territory or military government

commissions are tailored to the tribunals’ purpose and the exigencies
that necessitate their use. They may be employed “pending the estab
lishment of civil government,” Madsen, 343 U. S., at 354–355, which
may in some cases extend beyond the “cessation of hostilities,” id., at
348.
   27 So much may not be evident on cold review of the Civil War trials

often cited as precedent for this kind of tribunal because the commis
sions established during that conflict operated as both martial law or
military government tribunals and law-of-war commissions. Hence,
“military commanders began the practice [during the Civil War] of
using the same name, the same rules, and often the same tribunals” to
try both ordinary crimes and war crimes. Bickers, 34 Tex. Tech. L. Rev.,
at 908. “For the first time, accused horse thieves and alleged saboteurs
found themselves subject to trial by the same military commission.”
Id., at 909. The Civil War precedents must therefore be considered
with caution; as we recognized in Quirin, 317 U. S., at 29, and as
further discussed below, commissions convened during time of war but
under neither martial law nor military government may try only
offenses against the law of war.
                     Cite as: 548 U. S. ____ (2006)                   33

                         Opinion of STEVENS, J.

used the law-of-war military commission was during
World War II. In Quirin, this Court sanctioned President
Roosevelt’s use of such a tribunal to try Nazi saboteurs
captured on American soil during the War. 317 U. S. 1.
And in Yamashita, we held that a military commission
had jurisdiction to try a Japanese commander for failing to
prevent troops under his command from committing
atrocities in the Philippines. 327 U. S. 1.
   Quirin is the model the Government invokes most fre
quently to defend the commission convened to try Ham
dan. That is both appropriate and unsurprising. Since
Guantanamo Bay is neither enemy-occupied territory nor
under martial law, the law-of-war commission is the only
model available. At the same time, no more robust model
of executive power exists; Quirin represents the high-
water mark of military power to try enemy combatants for
war crimes.
   The classic treatise penned by Colonel William Win
throp, whom we have called “the ‘Blackstone of Military
Law,’ ” Reid v. Covert, 354 U. S. 1, 19, n. 38 (1957) (plural
ity opinion), describes at least four preconditions for exer
cise of jurisdiction by a tribunal of the type convened to try
Hamdan. First, “[a] military commission, (except where
otherwise authorized by statute), can legally assume
jurisdiction only of offenses committed within the field of
the command of the convening commander.” Winthrop
836. The “field of command” in these circumstances means
the “theatre of war.” Ibid. Second, the offense charged
“must have been committed within the period of the
war.”28 Id., at 837. No jurisdiction exists to try offenses
“committed either before or after the war.” Ibid. Third, a
military commission not established pursuant to martial
——————
  28 If the commission is established pursuant to martial law or military

government, its jurisdiction extends to offenses committed within “the
exercise of military government or martial law.” Winthrop 837.
34                     HAMDAN v. RUMSFELD

                         Opinion of STEVENS, J.

law or an occupation may try only “[i]ndividuals of the
enemy’s army who have been guilty of illegitimate warfare
or other offences in violation of the laws of war” and mem
bers of one’s own army “who, in time of war, become
chargeable with crimes or offences not cognizable, or
triable, by the criminal courts or under the Articles of
war.” Id., at 838. Finally, a law-of-war commission has
jurisdiction to try only two kinds of offense: “Violations of
the laws and usages of war cognizable by military tribu
nals only,” and “[b]reaches of military orders or regula
tions for which offenders are not legally triable by court-
martial under the Articles of war.” Id., at 839.29
   All parties agree that Colonel Winthrop’s treatise accu
rately describes the common law governing military com
missions, and that the jurisdictional limitations he identi
fies were incorporated in Article of War 15 and, later,
Article 21 of the UCMJ. It also is undisputed that Ham
dan’s commission lacks jurisdiction to try him unless the
charge “properly set[s] forth, not only the details of the
act charged, but the circumstances conferring jurisdic
tion.” Id., at 842 (emphasis in original). The question is
whether the preconditions designed to ensure that a mili
tary necessity exists to justify the use of this extraordi
nary tribunal have been satisfied here.
   The charge against Hamdan, described in detail in Part
I, supra, alleges a conspiracy extending over a number of
years, from 1996 to November 2001.30 All but two months
——————
  29 Winthrop adds as a fifth, albeit not-always-complied-with, criterion

that “the trial must be had within the theatre of war . . . ; that, if held
elsewhere, and where the civil courts are open and available, the
proceedings and sentence will be coram non judice.” Id., at 836. The
Government does not assert that Guantanamo Bay is a theater of war,
but instead suggests that neither Washington, D. C., in 1942 nor the
Philippines in 1945 qualified as a “war zone” either. Brief for Respon
dents 27; cf. Quirin, 317 U. S. 1; In re Yamashita, 327 U. S. 1 (1946).
  30 The elements of this conspiracy charge have been defined not by

Congress but by the President. See Military Commission Instruction
                      Cite as: 548 U. S. ____ (2006)                    35

                         Opinion of STEVENS, J.

of that more than 5-year-long period preceded the attacks
of September 11, 2001, and the enactment of the AUMF—
the Act of Congress on which the Government relies for
exercise of its war powers and thus for its authority to
convene military commissions.31 Neither the purported
——————
No. 2, 32 CFR §11.6 (2005).
   31 JUSTICE THOMAS would treat Osama bin Laden’s 1996 declaration of

jihad against Americans as the inception of the war. See post, at 7–10
(dissenting opinion). But even the Government does not go so far;
although the United States had for some time prior to the attacks of
September 11, 2001, been aggressively pursuing al Qaeda, neither in
the charging document nor in submissions before this Court has the
Government asserted that the President’s war powers were activated
prior to September 11, 2001. Cf. Brief for Respondents 25 (describing
the events of September 11, 2001, as “an act of war” that “triggered a
right to deploy military forces abroad to defend the United States by
combating al Qaeda”). JUSTICE THOMAS’ further argument that the
AUMF is “backward looking” and therefore authorizes trial by military
commission of crimes that occurred prior to the inception of war is
insupportable. See post, at 8, n. 3. If nothing else, Article 21 of the
UCMJ requires that the President comply with the law of war in his
use of military commissions. As explained in the text, the law of war
permits trial only of offenses “committed within the period of the war.”
Winthrop 837; see also Quirin, 317 U. S., at 28–29 (observing that law-
of-war military commissions may be used to try “those enemies who in
their attempt to thwart or impede our military effort have violated the
law of war” (emphasis added)). The sources that JUSTICE THOMAS relies
on to suggest otherwise simply do not support his position. Colonel
Green’s short exegesis on military commissions cites Howland for the
proposition that “[o]ffenses committed before a formal declaration of
war or before the declaration of martial law may be tried by military
commission.” The Military Commission, 42 Am. J. Int’l L. 832, 848
(1948) (emphases added) (cited post, at 9–10). Assuming that to be
true, nothing in our analysis turns on the admitted absence of either a
formal declaration of war or a declaration of martial law. Our focus
instead is on the September 11, 2001 attacks that the Government
characterizes as the relevant “act[s] of war,” and on the measure that
authorized the President’s deployment of military force—the AUMF.
Because we do not question the Government’s position that the war
commenced with the events of September 11, 2001, the Prize Cases, 2
Black 635 (1863) (cited post, at 2, 7, 8, and 10 (THOMAS, J., dissenting)),
36                    HAMDAN v. RUMSFELD

                        Opinion of STEVENS, J.

agreement with Osama bin Laden and others to commit
war crimes, nor a single overt act, is alleged to have oc
curred in a theater of war or on any specified date after
September 11, 2001. None of the overt acts that Hamdan is
alleged to have committed violates the law of war.
  These facts alone cast doubt on the legality of the charge
and, hence, the commission; as Winthrop makes plain, the
offense alleged must have been committed both in a thea
ter of war and during, not before, the relevant conflict.
But the deficiencies in the time and place allegations also
underscore—indeed are symptomatic of—the most serious
defect of this charge: The offense it alleges is not triable by
law-of-war military commission. See Yamashita, 327 U. S.,
at 13 (“Neither congressional action nor the military or
ders constituting the commission authorized it to place
petitioner on trial unless the charge proffered against him
——————
are not germane to the analysis.
   Finally, JUSTICE THOMAS’ assertion that Julius Otto Kuehn’s trial by
military commission “for conspiring with Japanese officials to betray
the United States fleet to the Imperial Japanese Government prior to
its attack on Pearl Harbor” stands as authoritative precedent for
Hamdan’s trial by commission, post, at 9, misses the mark in three
critical respects. First, Kuehn was tried for the federal espionage
crimes under what were then 50 U. S C. §§31, 32, and 34, not with
common-law violations of the law of war. See Hearings before the Joint
Committee on the Investigation of the Pearl Harbor Attack, 79th Cong.,
1st Sess., pt. 30, pp. 3067–3069 (1946). Second, he was tried by martial
law commission (a kind of commission JUSTICE THOMAS acknowledges is
not relevant to the analysis here, and whose jurisdiction extends to
offenses committed within “the exercise of . . . martial law,” Winthrop
837, see supra, n. 28), not a commission established exclusively to try
violations of the law of war. See ibid. Third, the martial law commis
sions established to try crimes in Hawaii were ultimately declared
illegal by this Court. See Duncan v. Kahanamoku, 327 U. S. 304, 324
(1946) (“The phrase ‘martial law’ as employed in [the Hawaiian Organic
Act], while intended to authorize the military to act vigorously for the
maintenance of an orderly civil government and for the defense of the
Islands against actual or threatened rebellion or invasion, was not in
tended to authorize the supplanting of courts by military tribunals”).
                      Cite as: 548 U. S. ____ (2006)                    37

                         Opinion of STEVENS, J.

is of a violation of the law of war”).32
——————
  32 JUSTICE  THOMAS adopts the remarkable view, not advocated by the
Government, that the charging document in this case actually includes
more than one charge: Conspiracy and several other ill-defined crimes,
like “joining an organization” that has a criminal purpose, “ ‘[b]eing a
guerilla,’ ” and aiding the enemy. See post, at 16–21, and n. 9. There
are innumerable problems with this approach.
   First, the crimes JUSTICE THOMAS identifies were not actually
charged. It is one thing to observe that charges before a military
commission “ ‘need not be stated with the precision of a common law
indictment,’ ” post, at 15, n. 7 (citation omitted); it is quite another to
say that a crime not charged may nonetheless be read into an indict
ment. Second, the Government plainly had available to it the tools and
the time it needed to charge petitioner with the various crimes JUSTICE
THOMAS refers to, if it believed they were supported by the allegations.
As JUSTICE THOMAS himself observes, see post, at 21, the crime of aiding
the enemy may, in circumstances where the accused owes allegiance to
the party whose enemy he is alleged to have aided, be triable by mili
tary commission pursuant to Article 104 of the UCMJ, 10 U. S. C. §904.
Indeed, the Government has charged detainees under this provision
when it has seen fit to do so. See Brief for David Hicks as Amicus
Curiae 7.
   Third, the cases JUSTICE THOMAS relies on to show that Hamdan may
be guilty of violations of the law of war not actually charged do not
support his argument. JUSTICE THOMAS begins by blurring the distinc
tion between those categories of “offender” who may be tried by military
commission (e.g., jayhawkers and the like) with the “offenses” that may
be so tried. Even when it comes to “ ‘being a guerilla,’ ” cf. post, at 18,
n. 9 (citation omitted), a label alone does not render a person suscepti
ble to execution or other criminal punishment; the charge of “ ‘being a
guerilla’ ” invariably is accompanied by the allegation that the defen
dant “ ‘took up arms’ ” as such. This is because, as explained by Judge
Advocate General Holt in a decision upholding the charge of “ ‘being a
guerilla’ ” as one recognized by “the universal usage of the times,” the
charge is simply shorthand (akin to “being a spy”) for “the perpetration
of a succession of similar acts” of violence. Record Books of the Judge
Advocate General Office, R. 3, 590.         The sources cited by JUSTICE
THOMAS confirm as much. See cases cited post, at 18, n. 9.
   Likewise, the suggestion that the Nuremberg precedents support
Hamdan’s conviction for the (uncharged) crime of joining a criminal
organization must fail. Cf. post, at 19–21. The convictions of certain
high-level Nazi officials for “membership in a criminal organization”
38                     HAMDAN v. RUMSFELD

                         Opinion of STEVENS, J.

   There is no suggestion that Congress has, in exercise of
its constitutional authority to “define and punish . . .
Offences against the Law of Nations,” U. S. Const., Art. I,
§8, cl. 10, positively identified “conspiracy” as a war
crime.33 As we explained in Quirin, that is not necessarily
fatal to the Government’s claim of authority to try the
alleged offense by military commission; Congress, through
Article 21 of the UCMJ, has “incorporated by reference”
the common law of war, which may render triable by
military commission certain offenses not defined by stat
ute. 317 U. S., at 30. When, however, neither the ele
ments of the offense nor the range of permissible punish
ments is defined by statute or treaty, the precedent must
be plain and unambiguous. To demand any less would be
to risk concentrating in military hands a degree of adjudi
cative and punitive power in excess of that contemplated
either by statute or by the Constitution. Cf. Loving v.
United States, 517 U. S. 748, 771 (1996) (acknowledging
that Congress “may not delegate the power to make laws”);
Reid, 354 U. S., at 23–24 (“The Founders envisioned the
army as a necessary institution, but one dangerous to lib
erty if not confined within its essential bounds”); The Feder
alist No. 47, p. 324 (J. Cooke ed. 1961) (J. Madison) (“The
accumulation of all powers legislative, executive and judici
——————
were secured pursuant to specific provisions of the Charter of the
International Military Tribunal that permitted indictment of individual
organization members following convictions of the organizations them
selves. See Arts. 9 and 10, in 1 Trial of the Major War Criminals
Before the International Military Tribunal 12 (1947). The initial plan
to use organizations’ convictions as predicates for mass individual trials
ultimately was abandoned. See T. Taylor, Anatomy of the Nuremberg
Trials: A Personal Memoir 584–585, 638 (1992).
  33 Cf. 10 U. S. C. §904 (making triable by military commission the

crime of aiding the enemy); §906 (same for spying); War Crimes Act of
1996, 18 U. S. C. §2441 (2000 ed. and Supp. III) (listing war crimes);
Foreign Operations, Export Financing, and Related Appropriations Act,
1998, §583, 111 Stat. 2436 (same).
                     Cite as: 548 U. S. ____ (2006)                   39

                         Opinion of STEVENS, J.

ary in the same hands . . . may justly be pronounced the
very definition of tyranny”).34
   This high standard was met in Quirin; the violation
there alleged was, by “universal agreement and practice”
both in this country and internationally, recognized as an
offense against the law of war. 317 U. S., at 30; see id., at
35–36 (“This precept of the law of war has been so recog
nized in practice both here and abroad, and has so gener
ally been accepted as valid by authorities on international
law that we think it must be regarded as a rule or princi
ple of the law of war recognized by this Government by its
enactment of the Fifteenth Article of War” (footnote omit
ted)). Although the picture arguably was less clear in
Yamashita, compare 327 U. S., at 16 (stating that the
provisions of the Fourth Hague Convention of 1907, 36
Stat. 2306, “plainly” required the defendant to control the
troops under his command), with 327 U. S., at 35 (Mur
phy, J., dissenting), the disagreement between the major
ity and the dissenters in that case concerned whether the
historic and textual evidence constituted clear precedent—
not whether clear precedent was required to justify trial
by law-of-war military commission.
   At a minimum, the Government must make a substan
tial showing that the crime for which it seeks to try a
——————
   34 While the common law necessarily is “evolutionary in nature,” post,

at 13 (THOMAS, J., dissenting), even in jurisdictions where common law
crimes are still part of the penal framework, an act does not become a
crime without its foundations having been firmly established in prece
dent. See, e.g., R. v. Rimmington, [2006] 2 All E. R. 257, 275–279
(House of Lords); id., at 279 (while “some degree of vagueness is inevi
table and development of the law is a recognised feature of common law
courts, . . . the law-making function of the courts must remain within
reasonable limits”); see also Rogers v. Tennessee, 532 U. S. 451, 472–
478 (2001) (SCALIA, J., dissenting). The caution that must be exercised
in the incremental development of common-law crimes by the judiciary
is, for the reasons explained in the text, all the more critical when
reviewing developments that stem from military action.
40                     HAMDAN v. RUMSFELD

                         Opinion of STEVENS, J.

defendant by military commission is acknowledged to be
an offense against the law of war. That burden is far from
satisfied here. The crime of “conspiracy” has rarely if ever
been tried as such in this country by any law-of-war mili
tary commission not exercising some other form of juris
diction,35 and does not appear in either the Geneva Con
ventions or the Hague Conventions—the major treaties on
the law of war.36 Winthrop explains that under the com
mon law governing military commissions, it is not enough
to intend to violate the law of war and commit overt acts
in furtherance of that intention unless the overt acts
either are themselves offenses against the law of war or
constitute steps sufficiently substantial to qualify as an
attempt. See Winthrop 841 (“[T]he jurisdiction of the
military commission should be restricted to cases of of
fence consisting in overt acts, i.e., in unlawful commissions
or actual attempts to commit, and not in intentions
——————
   35 The 19th-century trial of the “Lincoln conspirators,” even if prop

erly classified as a trial by law-of-war commission, cf. W. Rehnquist, All
the Laws But One: Civil Liberties in Wartime 165–167 (1998) (analyz
ing the conspiracy charges in light of ordinary criminal law principles
at the time), is at best an equivocal exception. Although the charge
against the defendants in that case accused them of “combining, con
federating, and conspiring together” to murder the President, they were
also charged (as we read the indictment, cf. post, at 23, n. 14 (THOMAS,
J., dissenting)) with “maliciously, unlawfully, and traitorously murder
ing the said Abraham Lincoln.” H. R. Doc. No. 314, 55th Cong., 1st
Sess., 696 (1899). Moreover, the Attorney General who wrote the
opinion defending the trial by military commission treated the charge
as if it alleged the substantive offense of assassination. See 11 Op.
Atty. Gen. 297 (1865) (analyzing the propriety of trying by military
commission “the offence of having assassinated the President”); see also
Mudd v. Caldera, 134 F. Supp. 2d 138, 140 (DC 2001).
   36 By contrast, the Geneva Conventions do extend liability for sub

stantive war crimes to those who “orde[r]” their commission, see Third
Geneva Convention, Art. 129, 6 U. S. T., at 3418, and this Court has
read the Fourth Hague Convention of 1907 to impose “command
responsibility” on military commanders for acts of their subordinates,
see Yamshita, 327 U. S., at 15–16.
                 Cite as: 548 U. S. ____ (2006)            41

                    Opinion of STEVENS, J.

merely” (emphasis in original)).
    The Government cites three sources that it says show
otherwise. First, it points out that the Nazi saboteurs in
Quirin were charged with conspiracy. See Brief for Re
spondents 27. Second, it observes that Winthrop at one
point in his treatise identifies conspiracy as an offense
“prosecuted by military commissions.” Ibid. (citing Win
throp 839, and n. 5). Finally, it notes that another mili
tary historian, Charles Roscoe Howland, lists conspiracy
“ ‘to violate the laws of war by destroying life or property
in aid of the enemy’ ” as an offense that was tried as a
violation of the law of war during the Civil War. Brief for
Respondents 27–28 (citing C. Howland, Digest of Opinions
of the Judge Advocates General of the Army 1071 (1912)
(hereinafter Howland)). On close analysis, however, these
sources at best lend little support to the Government’s
position and at worst undermine it. By any measure, they
fail to satisfy the high standard of clarity required to
justify the use of a military commission.
    That the defendants in Quirin were charged with con
spiracy is not persuasive, since the Court declined to
address whether the offense actually qualified as a viola
tion of the law of war—let alone one triable by military
commission. The Quirin defendants were charged with
the following offenses:
    “[I.] Violation of the law of war. 

    “[II.] Violation of Article 81 of the Articles of War, de

    fining the offense of relieving or attempting to relieve, 

    or corresponding with or giving intelligence to, the

    enemy.

    “[III.] Violation of Article 82, defining the offense of

    spying.

    “[IV.] Conspiracy to commit the offenses alleged in

    charges [I, II, and III].” 317 U. S., at 23. 

The Government, defending its charge, argued that the
42                 HAMDAN v. RUMSFELD

                     Opinion of STEVENS, J.

conspiracy alleged “constitute[d] an additional violation of
the law of war.” Id., at 15. The saboteurs disagreed; they
maintained that “[t]he charge of conspiracy can not stand
if the other charges fall.” Id., at 8. The Court, however,
declined to resolve the dispute. It concluded, first, that
the specification supporting Charge I adequately alleged a
“violation of the law of war” that was not “merely colorable
or without foundation.” Id., at 36. The facts the Court
deemed sufficient for this purpose were that the defen
dants, admitted enemy combatants, entered upon U. S.
territory in time of war without uniform “for the purpose
of destroying property used or useful in prosecuting the
war.” That act was “a hostile and warlike” one. Id., at 36,
37. The Court was careful in its decision to identify an
overt, “complete” act. Responding to the argument that
the saboteurs had “not actually committed or attempted to
commit any act of depredation or entered the theatre or
zone of active military operations” and therefore had not
violated the law of war, the Court responded that they had
actually “passed our military and naval lines and defenses
or went behind those lines, in civilian dress and with
hostile purpose.” Id., at 38. “The offense was complete
when with that purpose they entered—or, having so en
tered, they remained upon—our territory in time of war
without uniform or other appropriate means of identifica
tion.” Ibid.
   Turning to the other charges alleged, the Court ex
plained that “[s]ince the first specification of Charge I sets
forth a violation of the law of war, we have no occasion to
pass on the adequacy of the second specification of Charge
I, or to construe the 81st and 82nd Articles of War for the
purpose of ascertaining whether the specifications under
Charges II and III allege violations of those Articles or
whether if so construed they are constitutional.” Id., at
46. No mention was made at all of Charge IV—the con
spiracy charge.
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                    Opinion of STEVENS, J.

  If anything, Quirin supports Hamdan’s argument that
conspiracy is not a violation of the law of war. Not only
did the Court pointedly omit any discussion of the con
spiracy charge, but its analysis of Charge I placed special
emphasis on the completion of an offense; it took seriously
the saboteurs’ argument that there can be no violation of a
law of war—at least not one triable by military commis
sion—without the actual commission of or attempt to
commit a “hostile and warlike act.” Id., at 37–38.
  That limitation makes eminent sense when one consid
ers the necessity from whence this kind of military com
mission grew: The need to dispense swift justice, often in
the form of execution, to illegal belligerents captured on
the battlefield. See S. Rep. No. 130, 64th Cong., 1st Sess.,
p. 40 (1916) (testimony of Brig. Gen. Enoch H. Crowder)
(observing that Article of War 15 preserves the power of
“the military commander in the field in time of war” to use
military commissions (emphasis added)). The same ur
gency would not have been felt vis-à-vis enemies who had
done little more than agree to violate the laws of war. Cf.
31 Op. Atty. Gen. 356, 357, 361 (1918) (opining that a
German spy could not be tried by military commission
because, having been apprehended before entering “any
camp, fortification or other military premises of the
United States,” he had “committed [his offenses] outside of
the field of military operations”). The Quirin Court ac
knowledged as much when it described the President’s
authority to use law-of-war military commissions as the
power to “seize and subject to disciplinary measures those
enemies who in their attempt to thwart or impede our
military effort have violated the law of war.” 317 U. S., at
28–29 (emphasis added).
  Winthrop and Howland are only superficially more
helpful to the Government. Howland, granted, lists “con
spiracy by two or more to violate the laws of war by de
stroying life or property in aid of the enemy” as one of over
44                  HAMDAN v. RUMSFELD

                     Opinion of STEVENS, J.

20 “offenses against the laws and usages of war” “passed
upon and punished by military commissions.” Howland
1071. But while the records of cases that Howland cites
following his list of offenses against the law of war support
inclusion of the other offenses mentioned, they provide no
support for the inclusion of conspiracy as a violation of the
law of war. See ibid. (citing Record Books of the Judge
Advocate General Office, R. 2, 144; R. 3, 401, 589, 649; R.
4, 320; R. 5, 36, 590; R. 6, 20; R. 7, 413; R. 8, 529; R. 9,
149, 202, 225, 481, 524, 535; R. 10, 567; R. 11, 473, 513; R.
13, 125, 675; R. 16, 446; R. 21, 101, 280). Winthrop, ap
parently recognizing as much, excludes conspiracy of any
kind from his own list of offenses against the law of war.
See Winthrop 839–840.
   Winthrop does, unsurprisingly, include “criminal con
spiracies” in his list of “[c]rimes and statutory offenses
cognizable by State or U. S. courts” and triable by martial
law or military government commission. See id., at 839.
And, in a footnote, he cites several Civil War examples of
“conspiracies of this class, or of the first and second classes
combined.” Id., at 839, n. 5 (emphasis added). The Gov
ernment relies on this footnote for its contention that
conspiracy was triable both as an ordinary crime (a crime
of the “first class”) and, independently, as a war crime (a
crime of the “second class”). But the footnote will not
support the weight the Government places on it.
   As we have seen, the military commissions convened
during the Civil War functioned at once as martial law or
military government tribunals and as law-of-war commis
sions. See n. 27, supra. Accordingly, they regularly tried
war crimes and ordinary crimes together. Indeed, as
Howland observes, “[n]ot infrequently the crime, as
charged and found, was a combination of the two species of
offenses.” Howland 1071; see also Davis 310, n. 2; Win
throp 842. The example he gives is “ ‘murder in violation
of the laws of war.’ ” Howland 1071–1072. Winthrop’s
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                    Opinion of STEVENS, J.

conspiracy “of the first and second classes combined” is,
like Howland’s example, best understood as a species of
compound offense of the type tried by the hybrid military
commissions of the Civil War. It is not a stand-alone
offense against the law of war. Winthrop confirms this
understanding later in his discussion, when he empha
sizes that “overt acts” constituting war crimes are the only
proper subject at least of those military tribunals not
convened to stand in for local courts. Winthrop 841, and
nn. 22, 23 (emphasis in original) (citing W. Finlason,
Martial Law 130 (1867)).
   JUSTICE THOMAS cites as evidence that conspiracy is a
recognized violation of the law of war the Civil War in
dictment against Henry Wirz, which charged the defen
dant with “ ‘[m]aliciously, willfully, and traitorously . . .
combining, confederating, and conspiring [with others] to
injure the health and destroy the lives of soldiers in the
military service of the United States . . . to the end that
the armies of the United States might be weakened and
impaired, in violation of the laws and customs of war.’ ”
Post, at 24–25 (dissenting opinion) (quoting H. R. Doc. No.
314, 55th Cong., 3d Sess., 785 (1865); emphasis deleted).
As shown by the specification supporting that charge,
however, Wirz was alleged to have personally committed a
number of atrocities against his victims, including torture,
injection of prisoners with poison, and use of “ferocious
and bloodthirsty dogs” to “seize, tear, mangle, and maim
the bodies and limbs” of prisoners, many of whom died as
a result. Id., at 789–790. Crucially, Judge Advocate
General Holt determined that one of Wirz’s alleged co
conspirators, R. B. Winder, should not be tried by military
commission because there was as yet insufficient evidence
of his own personal involvement in the atrocities: “[I]n the
case of R. B. Winder, while the evidence at the trial of Wirz
was deemed by the court to implicate him in the conspiracy
against the lives of all Federal prisoners in rebel hands, no
46                     HAMDAN v. RUMSFELD

                         Opinion of STEVENS, J.

such specific overt acts of violation of the laws of war are
as yet fixed upon him as to make it expedient to prefer
formal charges and bring him to trial.” Id., at 783 (em
phases added).37
  Finally, international sources confirm that the crime
charged here is not a recognized violation of the law of
war.38 As observed above, see supra, at 40, none of the
major treaties governing the law of war identifies conspir
acy as a violation thereof. And the only “conspiracy”
crimes that have been recognized by international war
crimes tribunals (whose jurisdiction often extends beyond
war crimes proper to crimes against humanity and crimes
against the peace) are conspiracy to commit genocide and
common plan to wage aggressive war, which is a crime
against the peace and requires for its commission actual
participation in a “concrete plan to wage war.” 1 Trial of
——————
   37 The other examples JUSTICE THOMAS offers are no more availing.

The Civil War indictment against Robert Louden, cited post, at 25,
alleged a conspiracy, but not one in violation of the law of war. See War
Dept., General Court Martial Order No. 41, p. 20 (1864). A separate
charge of “ ‘[t]ransgression of the laws and customs of war’ ” made no
mention of conspiracy. Id., at 17. The charge against Lenger Grenfel
and others for conspiring to release rebel prisoners held in Chicago only
supports the observation, made in the text, that the Civil War tribunals
often charged hybrid crimes mixing elements of crimes ordinarily
triable in civilian courts (like treason) and violations of the law of war.
Judge Advocate General Holt, in recommending that Grenfel’s death
sentence be upheld (it was in fact commuted by Presidential decree, see
H. R. Doc. No. 314, at 725), explained that the accused “united himself
with traitors and malefactors for the overthrow of our Republic in the
interest of slavery.” Id., at 689.
   38 The Court in Quirin “assume[d] that there are acts regarded in

other countries, or by some writers on international law, as offenses
against the law of war which would not be triable by military tribunal
here, either because they are not recognized by our courts as violations
of the law of war or because they are of that class of offenses constitu
tionally triable only by a jury.” 317 U. S., at 29. We need not test the
validity of that assumption here because the international sources only
corroborate the domestic ones.
                    Cite as: 548 U. S. ____ (2006)                  47

                        Opinion of STEVENS, J.

the Major War Criminals Before the International Mili
tary Tribunal: Nuremberg, 14 November 1945–1 October
1946, p. 225 (1947). The International Military Tribunal
at Nuremberg, over the prosecution’s objections, pointedly
refused to recognize as a violation of the law of war con
spiracy to commit war crimes, see, e.g., 22 id., at 469,39
and convicted only Hitler’s most senior associates of con
spiracy to wage aggressive war, see S. Pomorski, Conspir
acy and Criminal Organization, in the Nuremberg Trial
and International Law 213, 233–235 (G. Ginsburgs & V.
Kudriavtsev eds. 1990). As one prominent figure from the
Nuremberg trials has explained, members of the Tribunal
objected to recognition of conspiracy as a violation of the
law of war on the ground that “[t]he Anglo-American
concept of conspiracy was not part of European legal
systems and arguably not an element of the internation
ally recognized laws of war.” T. Taylor, Anatomy of the
Nuremberg Trials: A Personal Memoir 36 (1992); see also
id., at 550 (observing that Francis Biddle, who as Attorney
General prosecuted the defendants in Quirin, thought the
French judge had made a “ ‘persuasive argument that
conspiracy in the truest sense is not known to interna
tional law’ ”).40
——————
  39 Accordingly,    the Tribunal determined to “disregard the
charges . . . that the defendants conspired to commit War Crimes and
Crimes against Humanity.” 22 Trial of the Major War Criminals
Before the International Military Tribunal 469 (1947); see also ibid.
(“[T]he Charter does not define as a separate crime any conspiracy
except the one to commit acts of aggressive war”).
   40 See also 15 United Nations War Crimes Commissions, Law Reports

of Trials of War Criminals 90–91 (1949) (observing that, although a few
individuals were charged with conspiracy under European domestic
criminal codes following World War II, “the United States Military
Tribunals” established at that time did not “recognis[e] as a separate
offence conspiracy to commit war crimes or crimes against humanity”).
The International Criminal Tribunal for the former Yugoslavia (ICTY),
drawing on the Nuremberg precedents, has adopted a “joint criminal
48                     HAMDAN v. RUMSFELD

                         Opinion of STEVENS, J.

   In sum, the sources that the Government and JUSTICE
THOMAS rely upon to show that conspiracy to violate the
law of war is itself a violation of the law of war in fact
demonstrate quite the opposite. Far from making the
requisite substantial showing, the Government has failed
even to offer a “merely colorable” case for inclusion of
conspiracy among those offenses cognizable by law-of-war
military commission. Cf. Quirin, 317 U. S., at 36. Be
cause the charge does not support the commission’s juris
diction, the commission lacks authority to try Hamdan.
   The charge’s shortcomings are not merely formal, but
are indicative of a broader inability on the Executive’s part
here to satisfy the most basic precondition—at least in the
absence of specific congressional authorization—for estab
lishment of military commissions: military necessity.
Hamdan’s tribunal was appointed not by a military com
mander in the field of battle, but by a retired major gen
eral stationed away from any active hostilities. Cf. Rasul
v. Bush, 542 U. S., at 487 (KENNEDY, J., concurring in
judgment) (observing that “Guantanamo Bay is . . . far
removed from any hostilities”). Hamdan is charged not
with an overt act for which he was caught redhanded in a
theater of war and which military efficiency demands be
tried expeditiously, but with an agreement the inception of
which long predated the attacks of September 11, 2001
and the AUMF. That may well be a crime,41 but it is not
——————
enterprise” theory of liability, but that is a species of liability for the
substantive offense (akin to aiding and abetting), not a crime on its
own. See Prosecutor v. Tadić, Judgment, Case No. IT–94–1–A (ICTY
App. Chamber, July 15, 1999); see also Prosecutor v. Milutinović,
Decision on Dragoljub Ojdanić’s Motion Challenging Jurisdiction—
Joint Criminal Enterprise, Case No. IT–99–37–AR72, ¶26 (ICTY App.
Chamber, May 21, 2003) (stating that “[c]riminal liability pursuant to a
joint criminal enterprise is not a liability for . . . conspiring to commit
crimes”).
   41 JUSTICE THOMAS’ suggestion that our conclusion precludes the Gov

ernment from bringing to justice those who conspire to commit acts of
                     Cite as: 548 U. S. ____ (2006)                    49

                          Opinion of the Court

an offense that “by the law of war may be tried
by military commissio[n].” 10 U. S. C. §821. None of the
overt acts alleged to have been committed in furtherance
of the agreement is itself a war crime, or even necessarily
occurred during time of, or in a theater of, war. Any ur
gent need for imposition or execution of judgment is ut
terly belied by the record; Hamdan was arrested in No
vember 2001 and he was not charged until mid-2004.
These simply are not the circumstances in which, by any
stretch of the historical evidence or this Court’s prece
dents, a military commission established by Executive
Order under the authority of Article 21 of the UCMJ may
lawfully try a person and subject him to punishment.
                              VI
   Whether or not the Government has charged Hamdan
with an offense against the law of war cognizable by mili
tary commission, the commission lacks power to proceed.
The UCMJ conditions the President’s use of military
commissions on compliance not only with the American
common law of war, but also with the rest of the UCMJ
itself, insofar as applicable, and with the “rules and pre
cepts of the law of nations,” Quirin, 317 U. S., at 28—
including, inter alia, the four Geneva Conventions signed
in 1949. See Yamashita, 327 U. S., at 20–21, 23–24. The
procedures that the Government has decreed will govern
Hamdan’s trial by commission violate these laws.
                          A
  The commission’s procedures are set forth in Commis
sion Order No. 1, which was amended most recently on
—————— 

terrorism is therefore wide of the mark. See post, at 8, n. 3; 28–30.

That conspiracy is not a violation of the law of war triable by military

commission does not mean the Government may not, for example,

prosecute by court-martial or in federal court those caught “plotting

terrorist atrocities like the bombing of the Khobar Towers.” Post, at 29. 

50                   HAMDAN v. RUMSFELD

                        Opinion of the Court

August 31, 2005—after Hamdan’s trial had already begun.
Every commission established pursuant to Commission
Order No. 1 must have a presiding officer and at least
three other members, all of whom must be commissioned
officers. §4(A)(1). The presiding officer’s job is to rule on
questions of law and other evidentiary and interlocutory
issues; the other members make findings and, if applica
ble, sentencing decisions. §4(A)(5). The accused is enti
tled to appointed military counsel and may hire civilian
counsel at his own expense so long as such counsel is a
U. S. citizen with security clearance “at the level SECRET
or higher.” §§4(C)(2)–(3).
   The accused also is entitled to a copy of the charge(s)
against him, both in English and his own language (if
different), to a presumption of innocence, and to certain
other rights typically afforded criminal defendants in
civilian courts and courts-martial. See §§5(A)–(P). These
rights are subject, however, to one glaring condition: The
accused and his civilian counsel may be excluded from,
and precluded from ever learning what evidence was
presented during, any part of the proceeding that either
the Appointing Authority or the presiding officer decides
to “close.” Grounds for such closure “include the protec
tion of information classified or classifiable . . . ; informa
tion protected by law or rule from unauthorized disclosure;
the physical safety of participants in Commission proceed
ings, including prospective witnesses; intelligence and law
enforcement sources, methods, or activities; and other
national security interests.” §6(B)(3).42 Appointed mili
tary defense counsel must be privy to these closed ses
sions, but may, at the presiding officer’s discretion, be
forbidden to reveal to his or her client what took place
therein. Ibid.
——————
  42 The accused also may be excluded from the proceedings if he “en

gages in disruptive conduct.” §5(K).
                    Cite as: 548 U. S. ____ (2006)                  51

                         Opinion of the Court

  Another striking feature of the rules governing Ham
dan’s commission is that they permit the admission of any
evidence that, in the opinion of the presiding officer,
“would have probative value to a reasonable person.”
§6(D)(1). Under this test, not only is testimonial hearsay
and evidence obtained through coercion fully admissible,
but neither live testimony nor witnesses’ written state
ments need be sworn. See §§6(D)(2)(b), (3). Moreover, the
accused and his civilian counsel may be denied access to
evidence in the form of “protected information” (which
includes classified information as well as “information
protected by law or rule from unauthorized disclosure” and
“information concerning other national security interests,”
§§6(B)(3), 6(D)(5)(a)(v)), so long as the presiding officer
concludes that the evidence is “probative” under §6(D)(1)
and that its admission without the accused’s knowledge
would not “result in the denial of a full and fair trial.”
§6(D)(5)(b).43 Finally, a presiding officer’s determination
that evidence “would not have probative value to a rea
sonable person” may be overridden by a majority of the
other commission members. §6(D)(1).
  Once all the evidence is in, the commission members (not
including the presiding officer) must vote on the accused’s
guilt. A two-thirds vote will suffice for both a verdict of
guilty and for imposition of any sentence not including
death (the imposition of which requires a unanimous vote).
§6(F). Any appeal is taken to a three-member review
panel composed of military officers and designated by the
Secretary of Defense, only one member of which need have
——————
  43 As the District Court observed, this section apparently permits

reception of testimony from a confidential informant in circumstances
where “Hamdan will not be permitted to hear the testimony, see the
witness’s face, or learn his name. If the government has information
developed by interrogation of witnesses in Afghanistan or elsewhere, it
can offer such evidence in transcript form, or even as summaries of
transcripts.” 344 F. Supp. 2d 152, 168 (DC 2004).
52                 HAMDAN v. RUMSFELD

                     Opinion of the Court

experience as a judge. §6(H)(4). The review panel is
directed to “disregard any variance from procedures speci
fied in this Order or elsewhere that would not materially
have affected the outcome of the trial before the Commis
sion.” Ibid. Once the panel makes its recommendation to
the Secretary of Defense, the Secretary can either remand
for further proceedings or forward the record to the Presi
dent with his recommendation as to final disposition.
§6(H)(5). The President then, unless he has delegated the
task to the Secretary, makes the “final decision.” §6(H)(6).
He may change the commission’s findings or sentence only
in a manner favorable to the accused. Ibid.
                              B
   Hamdan raises both general and particular objections to
the procedures set forth in Commission Order No. 1. His
general objection is that the procedures’ admitted devia
tion from those governing courts-martial itself renders the
commission illegal. Chief among his particular objections
are that he may, under the Commission Order, be con
victed based on evidence he has not seen or heard, and
that any evidence admitted against him need not comply
with the admissibility or relevance rules typically applica
ble in criminal trials and court-martial proceedings.
   The Government objects to our consideration of any
procedural challenge at this stage on the grounds that (1)
the abstention doctrine espoused in Councilman, 420 U. S.
738, precludes pre-enforcement review of procedural rules,
(2) Hamdan will be able to raise any such challenge follow
ing a “final decision” under the DTA, and (3) “there is . . .
no basis to presume, before the trial has even commenced,
that the trial will not be conducted in good faith and ac
cording to law.” Brief for Respondents 45–46, nn. 20–21.
The first of these contentions was disposed of in Part III,
supra, and neither of the latter two is sound.
   First, because Hamdan apparently is not subject to the
                    Cite as: 548 U. S. ____ (2006)                 53

                        Opinion of the Court

death penalty (at least as matters now stand) and may
receive a sentence shorter than 10 years’ imprisonment,
he has no automatic right to review of the commission’s
“final decision”44 before a federal court under the DTA.
See §1005(e)(3), 119 Stat. 2743. Second, contrary to the
Government’s assertion, there is a “basis to presume” that
the procedures employed during Hamdan’s trial will vio
late the law: The procedures are described with particular
ity in Commission Order No. 1, and implementation of
some of them has already occurred. One of Hamdan’s
complaints is that he will be, and indeed already has been,
excluded from his own trial. See Reply Brief for Petitioner
12; App. to Pet. for Cert. 45a. Under these circumstances,
review of the procedures in advance of a “final decision”—
the timing of which is left entirely to the discretion of the
President under the DTA—is appropriate. We turn, then,
to consider the merits of Hamdan’s procedural challenge.
                              C
  In part because the difference between military commis
sions and courts-martial originally was a difference of
jurisdiction alone, and in part to protect against abuse and
ensure evenhandedness under the pressures of war, the
procedures governing trials by military commission his
torically have been the same as those governing courts-
martial. See, e.g., 1 The War of the Rebellion 248 (2d
series 1894) (General Order 1 issued during the Civil War
required military commissions to “be constituted in a
similar manner and their proceedings be conducted ac
cording to the same general rules as courts-martial in
order to prevent abuses which might otherwise arise”).
Accounts of commentators from Winthrop through Gen
eral Crowder—who drafted Article of War 15 and whose

——————
  44 Any decision of the commission is not “final” until the President

renders it so. See Commission Order No. 1 §6(H)(6).
54                    HAMDAN v. RUMSFELD

                         Opinion of the Court

views have been deemed “authoritative” by this Court,
Madsen, 343 U. S., at 353—confirm as much.45 As re
cently as the Korean and Vietnam wars, during which use
of military commissions was contemplated but never
made, the principle of procedural parity was espoused as a
background assumption. See Paust, Antiterrorism Mili
tary Commissions: Courting Illegality, 23 Mich. J. Int’l L.
1, 3–5 (2001–2002).
   There is a glaring historical exception to this general
rule. The procedures and evidentiary rules used to try
General Yamashita near the end of World War II deviated
in significant respects from those then governing courts-
martial. See 327 U. S. 1. The force of that precedent,
however, has been seriously undermined by post-World
War II developments.
   Yamashita, from late 1944 until September 1945, was
Commanding General of the Fourteenth Army Group of
the Imperial Japanese Army, which had exercised control
over the Philippine Islands. On September 3, 1945, after
American forces regained control of the Philippines, Ya
mashita surrendered. Three weeks later, he was charged
with violations of the law of war. A few weeks after that,
he was arraigned before a military commission convened
in the Philippines. He pleaded not guilty, and his trial
lasted for two months. On December 7, 1945, Yamashita
was convicted and sentenced to hang. See id., at 5; id., at
31–34 (Murphy, J., dissenting). This Court upheld the
——————
  45 See Winthrop 835, and n. 81 (“military commissions are constituted

and composed, and their proceedings are conducted, similarly to gen
eral courts-martial”); id., at 841–842; S. Rep. No. 130, 64th Cong., 1st
Sess., 40 (1916) (testimony of Gen. Crowder) (“Both classes of courts
have the same procedure”); see also, e.g., H. Coppée, Field Manual of
Courts-Martial, p. 104 (1863) (“[Military] commissions are appointed by
the same authorities as those which may order courts-martial. They
are constituted in a manner similar to such courts, and their proceed
ings are conducted in exactly the same way, as to form, examination of
witnesses, etc.”).
                     Cite as: 548 U. S. ____ (2006)                   55

                          Opinion of the Court

denial of his petition for a writ of habeas corpus.
  The procedures and rules of evidence employed during
Yamashita’s trial departed so far from those used in
courts-martial that they generated an unusually long and
vociferous critique from two Members of this Court. See
id., at 41–81 (Rutledge, J., joined by Murphy, J., dissent
ing).46 Among the dissenters’ primary concerns was that
the commission had free rein to consider all evidence
“which in the commission’s opinion ‘would be of assistance
in proving or disproving the charge,’ without any of the
usual modes of authentication.” Id., at 49 (Rutledge, J.).
  The majority, however, did not pass on the merits of
Yamashita’s procedural challenges because it concluded
that his status disentitled him to any protection under the
Articles of War (specifically, those set forth in Article 38,
which would become Article 36 of the UCMJ) or the Ge
neva Convention of 1929, 47 Stat. 2021 (1929 Geneva
Convention). The Court explained that Yamashita was
neither a “person made subject to the Articles of War by
Article 2” thereof, 327 U. S., at 20, nor a protected pris
oner of war being tried for crimes committed during his
detention, id., at 21.
  At least partially in response to subsequent criticism of
General Yamashita’s trial, the UCMJ’s codification of the
Articles of War after World War II expanded the category
of persons subject thereto to include defendants in Yama
——————
  46 The  dissenters’ views are summarized in the following passage:
   “It is outside our basic scheme to condemn men without giving
reasonable opportunity for preparing defense; in capital or other
serious crimes to convict on ‘official documents . . .; affidavits; . . .
documents or translations thereof; diaries . . ., photographs, motion
picture films, and . . . newspapers” or on hearsay, once, twice or thrice
removed, more particularly when the documentary evidence or some of
it is prepared ex parte by the prosecuting authority and includes not
only opinion but conclusions of guilt. Nor in such cases do we deny the
rights of confrontation of witnesses and cross-examination.” Yama
shita, 327 U. S., at 44 (footnotes omitted).
56                     HAMDAN v. RUMSFELD

                          Opinion of the Court

shita’s (and Hamdan’s) position,47 and the Third Geneva
Convention of 1949 extended prisoner-of-war protections
to individuals tried for crimes committed before their
capture. See 3 Int’l Comm. of Red Cross,48 Commentary:
Geneva Convention Relative to the Treatment of Prisoners
of War 413 (1960) (hereinafter GCIII Commentary) (ex
plaining that Article 85, which extends the Convention’s
protections to “[p]risoners of war prosecuted under the
laws of the Detaining Power for acts committed prior to
capture,” was adopted in response to judicial interpreta
tions of the 1929 Convention, including this Court’s deci
sion in Yamashita). The most notorious exception to the
principle of uniformity, then, has been stripped of its
precedential value.
   The uniformity principle is not an inflexible one; it does
not preclude all departures from the procedures dictated
for use by courts-martial. But any departure must be
tailored to the exigency that necessitates it. See Winthrop
835, n. 81. That understanding is reflected in Article 36 of
the UCMJ, which provides:

——————
  47 Article2 of the UCMJ now reads:
  “(a) The following persons are subject to [the UCMJ]:
  “(9) Prisoners of war in custody of the armed forces.
   “(12) Subject to any treaty or agreement to which the United States is
or may be a party or to any accepted rule of international law, persons
within an area leased by or otherwise reserved or acquired for the use
of the United States which is under the control of the Secretary con
cerned and which is outside the United States and outside the Com
monwealth of Puerto Rico, Guam, and the Virgin Islands.” 10 U. S. C.
§802(a).
   Guantanamo Bay is such a leased area. See Rasul v. Bush, 542 U. S.
466, 471 (2004).
   48 The International Committee of the Red Cross is referred to by

name in several provisions of the 1949 Geneva Conventions and is the
body that drafted and published the official commentary to the Conven
tions. Though not binding law, the commentary is, as the parties
recognize, relevant in interpreting the Conventions’ provisions.
                 Cite as: 548 U. S. ____ (2006)          57

                     Opinion of the Court

      “(a) The procedure, including modes of proof, in
    cases before courts-martial, courts of inquiry, military
    commissions, and other military tribunals may be
    prescribed by the President by regulations which
    shall, so far as he considers practicable, apply the
    principles of law and the rules of evidence generally
    recognized in the trial of criminal cases in the United
    States district courts, but which may not be contrary
    to or inconsistent with this chapter.
      “(b) All rules and regulations made under this arti
    cle shall be uniform insofar as practicable and shall be
    reported to Congress.” 70A Stat. 50.
  Article 36 places two restrictions on the President’s
power to promulgate rules of procedure for courts-martial
and military commissions alike. First, no procedural rule
he adopts may be “contrary to or inconsistent with” the
UCMJ—however practical it may seem. Second, the rules
adopted must be “uniform insofar as practicable.” That is,
the rules applied to military commissions must be the
same as those applied to courts-martial unless such uni
formity proves impracticable.
  Hamdan argues that Commission Order No. 1 violates
both of these restrictions; he maintains that the proce
dures described in the Commission Order are inconsistent
with the UCMJ and that the Government has offered no
explanation for their deviation from the procedures gov
erning courts-martial, which are set forth in the Manual
for Courts-Martial, United States (2005 ed.) (Manual for
Courts-Martial).    Among the inconsistencies Hamdan
identifies is that between §6 of the Commission Order,
which permits exclusion of the accused from proceedings
and denial of his access to evidence in certain circum
stances, and the UCMJ’s requirement that “[a]ll . . . pro
ceedings” other than votes and deliberations by courts-
martial “shall be made a part of the record and shall be in
58                     HAMDAN v. RUMSFELD

                          Opinion of the Court

the presence of the accused.” 10 U. S. C. A. §839(c) (Supp.
2006). Hamdan also observes that the Commission Order
dispenses with virtually all evidentiary rules applicable in
courts-martial.
  The Government has three responses. First, it argues,
only 9 of the UCMJ’s 158 Articles—the ones that expressly
mention “military commissions”49—actually apply to com
missions, and Commission Order No. 1 sets forth no pro
cedure that is “contrary to or inconsistent with” those 9
provisions. Second, the Government contends, military
commissions would be of no use if the President were
hamstrung by those provisions of the UCMJ that govern
courts-martial. Finally, the President’s determination
that “the danger to the safety of the United States and the
nature of international terrorism” renders it impracticable
“to apply in military commissions . . . the principles of law
and rules of evidence generally recognized in the trial of
criminal cases in the United States district courts,” No
vember 13 Order §1(f), is, in the Government’s view, ex
planation enough for any deviation from court-martial
procedures. See Brief for Respondents 43–47, and n. 22.
——————
  49 Aside from Articles 21 and 36, discussed at length in the text, the

other seven Articles that expressly reference military commissions are:
(1) 28 (requiring appointment of reporters and interpreters); (2) 47
(making it a crime to refuse to appear or testify “before a court-martial,
military commission, court of inquiry, or any other military court or
board”); (3) 48 (allowing a “court-martial, provost court, or military
commission” to punish a person for contempt); (4) 49(d) (permitting
admission into evidence of a “duly authenticated deposition taken upon
reasonable notice to the other parties” only if “admissible under the
rules of evidence” and only if the witness is otherwise unavailable); (5)
50 (permitting admission into evidence of records of courts of inquiry “if
otherwise admissible under the rules of evidence,” and if certain other
requirements are met); (6) 104 (providing that a person accused of
aiding the enemy may be sentenced to death or other punishment by
military commission or court-martial); and (7) 106 (mandating the
death penalty for spies convicted before military commission or court-
martial).
                     Cite as: 548 U. S. ____ (2006)                    59

                          Opinion of the Court

   Hamdan has the better of this argument. Without
reaching the question whether any provision of Commis
sion Order No. 1 is strictly “contrary to or inconsistent
with” other provisions of the UCMJ, we conclude that the
“practicability” determination the President has made is
insufficient to justify variances from the procedures gov
erning courts-martial. Subsection (b) of Article 36 was
added after World War II, and requires a different show
ing of impracticability from the one required by subsection
(a). Subsection (a) requires that the rules the President
promulgates for courts-martial, provost courts, and mili
tary commissions alike conform to those that govern pro
cedures in Article III courts, “so far as he considers practi
cable.” 10 U. S. C. §836(a) (emphasis added). Subsection
(b), by contrast, demands that the rules applied in courts-
martial, provost courts, and military commissions—
whether or not they conform with the Federal Rules of
Evidence—be “uniform insofar as practicable.” §836(b)
(emphasis added). Under the latter provision, then, the
rules set forth in the Manual for Courts-Martial must
apply to military commissions unless impracticable.50
   The President here has determined, pursuant to subsec
tion (a), that it is impracticable to apply the rules and
principles of law that govern “the trial of criminal cases in
——————
   50 JUSTICE THOMAS relies on the legislative history of the UCMJ to

argue that Congress’ adoption of Article 36(b) in the wake of World War
II was “motivated” solely by a desire for “uniformity across the separate
branches of the armed services.” Post, at 35. But even if Congress was
concerned with ensuring uniformity across service branches, that does
not mean it did not also intend to codify the longstanding practice of
procedural parity between courts-martial and other military tribunals.
Indeed, the suggestion that Congress did not intend uniformity across
tribunal types is belied by the textual proximity of subsection (a) (which
requires that the rules governing criminal trials in federal district
courts apply, absent the President’s determination of impracticability,
to courts-martial, provost courts, and military commissions alike) and
subsection (b) (which imposes the uniformity requirement).
60                    HAMDAN v. RUMSFELD

                         Opinion of the Court

the United States district courts,” §836(a), to Hamdan’s
commission. We assume that complete deference is owed
that determination. The President has not, however,
made a similar official determination that it is impractica
ble to apply the rules for courts-martial.51 And even if
subsection (b)’s requirements may be satisfied without
such an official determination, the requirements of that
subsection are not satisfied here.
  Nothing in the record before us demonstrates that it
would be impracticable to apply court-martial rules in this
case. There is no suggestion, for example, of any logistical
difficulty in securing properly sworn and authenticated
evidence or in applying the usual principles of relevance
and admissibility. Assuming arguendo that the reasons
articulated in the President’s Article 36(a) determination
ought to be considered in evaluating the impracticability
of applying court-martial rules, the only reason offered in
support of that determination is the danger posed by
international terrorism.52 Without for one moment under
estimating that danger, it is not evident to us why it
——————
  51 We  may assume that such a determination would be entitled to a
measure of deference. For the reasons given by JUSTICE KENNEDY, see
post, at 5 (opinion concurring in part), however, the level of deference
accorded to a determination made under subsection (b) presum
ably would not be as high as that accorded to a determination under
subsection (a).
  52 JUSTICE THOMAS looks not to the President’s official Article 36(a)

determination, but instead to press statements made by the Secretary
of Defense and the Under Secretary of Defense for Policy. See post, at
36–38 (dissenting opinion). We have not heretofore, in evaluating the
legality of Executive action, deferred to comments made by such offi
cials to the media. Moreover, the only additional reason the comments
provide—aside from the general danger posed by international terror
ism—for departures from court-martial procedures is the need to
protect classified information. As we explain in the text, and as
JUSTICE KENNEDY elaborates in his separate opinion, the structural and
procedural defects of Hamdan’s commission extend far beyond rules
preventing access to classified information.
                     Cite as: 548 U. S. ____ (2006)               61

                         Opinion of the Court

should require, in the case of Hamdan’s trial, any variance
from the rules that govern courts-martial.
   The absence of any showing of impracticability is par
ticularly disturbing when considered in light of the clear
and admitted failure to apply one of the most fundamental
protections afforded not just by the Manual for Courts-
Martial but also by the UCMJ itself: the right to be pre
sent. See 10 U. S. C. A. §839(c) (Supp. 2006). Whether or
not that departure technically is “contrary to or inconsis
tent with” the terms of the UCMJ, 10 U. S. C. §836(a), the
jettisoning of so basic a right cannot lightly be excused as
“practicable.”
   Under the circumstances, then, the rules applicable in
courts-martial must apply. Since it is undisputed that
Commission Order No. 1 deviates in many significant
respects from those rules, it necessarily violates Article
36(b).
   The Government’s objection that requiring compliance
with the court-martial rules imposes an undue burden
both ignores the plain meaning of Article 36(b) and mis
understands the purpose and the history of military com
missions. The military commission was not born of a
desire to dispense a more summary form of justice than is
afforded by courts-martial; it developed, rather, as a tri
bunal of necessity to be employed when courts-martial
lacked jurisdiction over either the accused or the subject
matter. See Winthrop 831. Exigency lent the commission
its legitimacy, but did not further justify the wholesale
jettisoning of procedural protections. That history ex
plains why the military commission’s procedures typically
have been the ones used by courts-martial. That the
jurisdiction of the two tribunals today may sometimes
overlap, see Madsen, 343 U. S., at 354, does not detract
from the force of this history;53 Article 21 did not trans
——————
 53 JUSTICE   THOMAS relies extensively on Madsen for the proposition
62                     HAMDAN v. RUMSFELD

                          Opinion of the Court

form the military commission from a tribunal of true
exigency into a more convenient adjudicatory tool. Article
36, confirming as much, strikes a careful balance between
uniform procedure and the need to accommodate exigen
cies that may sometimes arise in a theater of war. That
Article not having been complied with here, the rules
specified for Hamdan’s trial are illegal.54
                             D
  The procedures adopted to try Hamdan also violate the
Geneva Conventions. The Court of Appeals dismissed
Hamdan’s Geneva Convention challenge on three inde
pendent grounds: (1) the Geneva Conventions are not judi
cially enforceable; (2) Hamdan in any event is not entitled
to their protections; and (3) even if he is entitled to their
protections, Councilman abstention is appropriate. Judge
Williams, concurring, rejected the second ground but
agreed with the majority respecting the first and the last.
As we explained in Part III, supra, the abstention rule
applied in Councilman, 420 U. S. 738, is not applicable
here.55 And for the reasons that follow, we hold that
——————
that the President has free rein to set the procedures that govern
military commissions. See post, at 30, 31, 33, n. 16, 34, and 45. That
reliance is misplaced. Not only did Madsen not involve a law-of-war
military commission, but (1) the petitioner there did not challenge the
procedures used to try her, (2) the UCMJ, with its new Article 36(b),
did not become effective until May 31, 1951, after the petitioner’s trial,
see 343 U. S., at 345, n. 6, and (3) the procedures used to try the peti
tioner actually afforded more protection than those used in courts-
martial, see id., at 358–360; see also id., at 358 (“[T]he Military Gov
ernment Courts for Germany . . . have had a less military character
than that of courts-martial”).
   54 Prior to the enactment of Article 36(b), it may well have been the

case that a deviation from the rules governing courts-martial would not
have rendered the military commission “ ‘illegal.’ ” Post, at 30–31, n. 16
(THOMAS, J., dissenting) (quoting Winthrop 841). Article 36(b), how
ever, imposes a statutory command that must be heeded.
   55 JUSTICE THOMAS makes the different argument that Hamdan’s
                     Cite as: 548 U. S. ____ (2006)                  63

                         Opinion of the Court

neither of the other grounds the Court of Appeals gave for
its decision is persuasive.
                              i
   The Court of Appeals relied on Johnson v. Eisentrager,
339 U. S. 763 (1950), to hold that Hamdan could not in
voke the Geneva Conventions to challenge the Govern
ment’s plan to prosecute him in accordance with Commis
sion Order No. 1. Eisentrager involved a challenge by 21
German nationals to their 1945 convictions for war crimes
by a military tribunal convened in Nanking, China, and to
their subsequent imprisonment in occupied Germany. The
petitioners argued, inter alia, that the 1929 Geneva Con
vention rendered illegal some of the procedures employed
during their trials, which they said deviated impermissi
bly from the procedures used by courts-martial to try
American soldiers. See id., at 789. We rejected that claim
on the merits because the petitioners (unlike Hamdan
here) had failed to identify any prejudicial disparity “be
tween the Commission that tried [them] and those that
would try an offending soldier of the American forces of
like rank,” and in any event could claim no protection,
under the 1929 Convention, during trials for crimes that
occurred before their confinement as prisoners of war. Id.,
at 790.56
   Buried in a footnote of the opinion, however, is this
curious statement suggesting that the Court lacked power
even to consider the merits of the Geneva Convention
argument:
——————
Geneva Convention challenge is not yet “ripe” because he has yet to be
sentenced. See post, at 43–45. This is really just a species of the
abstention argument we have already rejected. See Part III, supra.
The text of the Geneva Conventions does not direct an accused to wait
until sentence is imposed to challenge the legality of the tribunal that
is to try him.
   56 As explained in Part VI–C, supra, that is no longer true under the

1949 Conventions.
64                     HAMDAN v. RUMSFELD

                          Opinion of the Court

     “We are not holding that these prisoners have no right
     which the military authorities are bound to respect.
     The United States, by the Geneva Convention of July
     27, 1929, 47 Stat. 2021, concluded with forty-six other
     countries, including the German Reich, an agreement
     upon the treatment to be accorded captives. These
     prisoners claim to be and are entitled to its protection.
     It is, however, the obvious scheme of the Agreement
     that responsibility for observance and enforcement of
     these rights is upon political and military authorities.
     Rights of alien enemies are vindicated under it only
     through protests and intervention of protecting pow
     ers as the rights of our citizens against foreign gov
     ernments are vindicated only by Presidential inter
     vention.” Id., at 789, n. 14.
The Court of Appeals, on the strength of this footnote, held
that “the 1949 Geneva Convention does not confer upon
Hamdan a right to enforce its provisions in court.” 415
F. 3d, at 40.
  Whatever else might be said about the Eisentrager
footnote, it does not control this case. We may assume
that “the obvious scheme” of the 1949 Conventions is
identical in all relevant respects to that of the 1929 Con
vention,57 and even that that scheme would, absent some
other provision of law, preclude Hamdan’s invocation of
the Convention’s provisions as an independent source of
law binding the Government’s actions and furnishing
petitioner with any enforceable right.58 For, regardless of
——————
  57 But   see, e.g., 4 Int’l Comm. of Red Cross, Commentary: Geneva
Convention Relative to the Protection of Civilian Persons in Time of
War 21 (1958) (hereinafter GCIV Commentary) (the 1949 Geneva
Conventions were written “first and foremost to protect individuals,
and not to serve State interests”); GCIII Commentary 91 (“It was not
. . . until the Conventions of 1949 . . . that the existence of ‘rights’
conferred in prisoners of war was affirmed”).
    58 But see generally Brief for Louis Henkin et al. as Amici Curiae; 1
                      Cite as: 548 U. S. ____ (2006)                    65

                          Opinion of the Court

the nature of the rights conferred on Hamdan, cf. United
States v. Rauscher, 119 U. S. 407 (1886), they are, as the
Government does not dispute, part of the law of war. See
Hamdi, 542 U. S., at 520–521 (plurality opinion). And
compliance with the law of war is the condition upon
which the authority set forth in Article 21 is granted.
                               ii
   For the Court of Appeals, acknowledgment of that condi
tion was no bar to Hamdan’s trial by commission. As an
alternative to its holding that Hamdan could not invoke
the Geneva Conventions at all, the Court of Appeals con
cluded that the Conventions did not in any event apply to
the armed conflict during which Hamdan was captured.
The court accepted the Executive’s assertions that Ham
dan was captured in connection with the United States’
war with al Qaeda and that that war is distinct from the
war with the Taliban in Afghanistan. It further reasoned
that the war with al Qaeda evades the reach of the Geneva
Conventions. See 415 F. 3d, at 41–42. We, like Judge
Williams, disagree with the latter conclusion.
   The conflict with al Qaeda is not, according to the Gov
ernment, a conflict to which the full protections afforded
detainees under the 1949 Geneva Conventions apply
because Article 2 of those Conventions (which appears in
all four Conventions) renders the full protections applica
ble only to “all cases of declared war or of any other armed
conflict which may arise between two or more of the High
Contracting Parties.” 6 U. S. T., at 3318.59 Since Hamdan
——————
Int’l Comm. for the Red Cross, Commentary: Geneva Convention for the
Amelioration of the Condition of the Wounded and Sick in Armed Forces
in the Field 84 (1952) (“It should be possible in States which are parties
to the Convention . . . for the rules of the Convention to be evoked before
an appropriate national court by the protected person who has suffered a
violation”); GCII Commentary 92; GCIV Commentary 79.
  59 For convenience’s sake, we use citations to the Third Geneva Con

vention only.
66                     HAMDAN v. RUMSFELD

                          Opinion of the Court

was captured and detained incident to the conflict with al
Qaeda and not the conflict with the Taliban, and since al
Qaeda, unlike Afghanistan, is not a “High Contracting
Party”—i.e., a signatory of the Conventions, the protec
tions of those Conventions are not, it is argued, applicable
to Hamdan.60
   We need not decide the merits of this argument because
there is at least one provision of the Geneva Conventions
that applies here even if the relevant conflict is not one
between signatories.61 Article 3, often referred to as Com
mon Article 3 because, like Article 2, it appears in all four
Geneva Conventions, provides that in a “conflict not of an
international character occurring in the territory of one of
the High Contracting Parties, each Party62 to the conflict
shall be bound to apply, as a minimum,” certain provisions
protecting “[p]ersons taking no active part in the hostili
ties, including members of armed forces who have laid
——————
   60 The President has stated that the conflict with the Taliban is a con

flict to which the Geneva Conventions apply. See White House Memo
randum, Humane Treatment of Taliban and al Qaeda Detainees 2
(Feb. 7, 2002), available at http://www.justicescholars.org/pegc/archive/
White_House/bush_memo_20020207_ed.pdf (hereinafter White House
Memorandum).
   61 Hamdan observes that Article 5 of the Third Geneva Convention

requires that if there be “any doubt” whether he is entitled to prisoner-
of-war protections, he must be afforded those protections until his
status is determined by a “competent tribunal.” 6 U. S. T., at 3324. See
also Headquarters Depts. of Army, Navy, Air Force, and Marine Corps,
Army Regulation 190–8, Enemy Prisoners of War, Retained Personnel,
Civilian Internees and Other Detainees (1997), App. 116. Because we
hold that Hamdan may not, in any event, be tried by the military
commission the President has convened pursuant to the November 13
Order and Commission Order No. 1, the question whether his potential
status as a prisoner of war independently renders illegal his trial by
military commission may be reserved.
   62 The term “Party” here has the broadest possible meaning; a Party

need neither be a signatory of the Convention nor “even represent a
legal entity capable of undertaking international obligations.” GCIII
Commentary 37.
                 Cite as: 548 U. S. ____ (2006)           67

                     Opinion of the Court

down their arms and those placed hors de combat by . . .
detention.” Id., at 3318. One such provision prohibits “the
passing of sentences and the carrying out of executions
without previous judgment pronounced by a regularly
constituted court affording all the judicial guarantees
which are recognized as indispensable by civilized peo
ples.” Ibid.
   The Court of Appeals thought, and the Government
asserts, that Common Article 3 does not apply to Hamdan
because the conflict with al Qaeda, being “ ‘international in
scope,’ ” does not qualify as a “ ‘conflict not of an interna
tional character.’ ” 415 F. 3d, at 41. That reasoning is
erroneous. The term “conflict not of an international
character” is used here in contradistinction to a conflict
between nations. So much is demonstrated by the “fun
damental logic [of] the Convention’s provisions on its
application.” Id., at 44 (Williams, J., concurring). Com
mon Article 2 provides that “the present Convention shall
apply to all cases of declared war or of any other armed
conflict which may arise between two or more of the High
Contracting Parties.” 6 U. S. T., at 3318 (Art. 2, ¶1). High
Contracting Parties (signatories) also must abide by all
terms of the Conventions vis-à-vis one another even if one
party to the conflict is a nonsignatory “Power,” and must
so abide vis-à-vis the nonsignatory if “the latter accepts
and applies” those terms. Ibid. (Art. 2, ¶3). Common
Article 3, by contrast, affords some minimal protection,
falling short of full protection under the Conventions, to
individuals associated with neither a signatory nor even a
nonsignatory “Power” who are involved in a conflict “in the
territory of” a signatory. The latter kind of conflict is
distinguishable from the conflict described in Common
Article 2 chiefly because it does not involve a clash be
tween nations (whether signatories or not). In context,
then, the phrase “not of an international character” bears
its literal meaning. See, e.g., J. Bentham, Introduction to
68                     HAMDAN v. RUMSFELD

                          Opinion of the Court

the Principles of Morals and Legislation 6, 296 (J. Burns &
H. Hart eds. 1970) (using the term “international law” as a
“new though not inexpressive appellation” meaning “be
twixt nation and nation”; defining “international” to in
clude “mutual transactions between sovereigns as such”);
Commentary on the Additional Protocols to the Geneva
Conventions of 12 August 1949, p. 1351 (1987) (“[A] non-
international armed conflict is distinct from an interna
tional armed conflict because of the legal status of the
entities opposing each other”).
   Although the official commentaries accompanying
Common Article 3 indicate that an important purpose of
the provision was to furnish minimal protection to rebels
involved in one kind of “conflict not of an international
character,” i.e., a civil war, see GCIII Commentary 36–37,
the commentaries also make clear “that the scope of the
Article must be as wide as possible,” id., at 36.63 In fact,
limiting language that would have rendered Common
Article 3 applicable “especially [to] cases of civil war,
colonial conflicts, or wars of religion,” was omitted from
the final version of the Article, which coupled broader
scope of application with a narrower range of rights than
did earlier proposed iterations. See GCIII Commentary
42–43.
——————
  63 See also GCIII Commentary 35 (Common Article 3 “has the merit of

being simple and clear. . . . Its observance does not depend upon pre
liminary discussions on the nature of the conflict”); GCIV Commentary
51 (“[N]obody in enemy hands can be outside the law”); U. S. Army
Judge Advocate General’s Legal Center and School, Dept. of the Army,
Law of War Handbook 144 (2004) (Common Article 3 “serves as a
‘minimum yardstick of protection in all conflicts, not just internal
armed conflicts’ ” (quoting Nicaragua v. United States, 1986 I. C. J. 14,
¶218, 25 I. L. M. 1023)); Prosecutor v. Tadić, Case No. IT–94–1, Deci
sion on the Defence Motion for Interlocutory Appeal on Jurisdiction,
¶102 (ICTY App. Chamber, Oct. 2, 1995) (stating that “the character
of the conflict is irrelevant” in deciding whether Common Article 3
applies).
                    Cite as: 548 U. S. ____ (2006)                  69

                         Opinion of the Court

                              iii
   Common Article 3, then, is applicable here and, as
indicated above, requires that Hamdan be tried by a
“regularly constituted court affording all the judicial guar
antees which are recognized as indispensable by civilized
peoples.” 6 U. S. T., at 3320 (Art. 3, ¶1(d)). While the
term “regularly constituted court” is not specifically de
fined in either Common Article 3 or its accompanying
commentary, other sources disclose its core meaning. The
commentary accompanying a provision of the Fourth
Geneva Convention, for example, defines “ ‘regularly con
stituted’ ” tribunals to include “ordinary military courts”
and “definitely exclud[e] all special tribunals.” GCIV
Commentary 340 (defining the term “properly constituted”
in Article 66, which the commentary treats as identical to
“regularly constituted”);64 see also Yamashita, 327 U. S.,
at 44 (Rutledge, J., dissenting) (describing military com
mission as a court “specially constituted for a particular
trial”). And one of the Red Cross’ own treatises defines
“regularly constituted court” as used in Common Article 3
to mean “established and organized in accordance with the
laws and procedures already in force in a country.” Int’l
Comm. of Red Cross, 1 Customary International Humani
tarian Law 355 (2005); see also GCIV Commentary 340
(observing that “ordinary military courts” will “be set up
in accordance with the recognized principles governing the
administration of justice”).
   The Government offers only a cursory defense of Ham
dan’s military commission in light of Common Article 3.
See Brief for Respondents 49–50. As JUSTICE KENNEDY
explains, that defense fails because “[t]he regular military
courts in our system are the courts-martial established by
——————
  64 Thecommentary’s assumption that the terms “properly constituted”
and “regularly constituted” are interchangeable is beyond reproach; the
French version of Article 66, which is equally authoritative, uses the
term “régulièrement constitués” in place of “properly constituted.”
70                     HAMDAN v. RUMSFELD

                         Opinion of Sthe Court
                          Opinion of TEVENS, J.

congressional statutes.” Post, at 8 (opinion concurring in
part). At a minimum, a military commission “can be
‘regularly constituted’ by the standards of our military
justice system only if some practical need explains devia
tions from court-martial practice.” Post, at 10. As we
have explained, see Part VI–C, supra, no such need has
been demonstrated here.65
                              iv
   Inextricably intertwined with the question of regular
constitution is the evaluation of the procedures governing
the tribunal and whether they afford “all the judicial
guarantees which are recognized as indispensable by
civilized peoples.” 6 U. S. T., at 3320 (Art. 3, ¶1(d)). Like
the phrase “regularly constituted court,” this phrase is not
defined in the text of the Geneva Conventions. But it
must be understood to incorporate at least the barest of
those trial protections that have been recognized by cus
tomary international law. Many of these are described in
Article 75 of Protocol I to the Geneva Conventions of 1949,
adopted in 1977 (Protocol I). Although the United States
declined to ratify Protocol I, its objections were not to
Article 75 thereof. Indeed, it appears that the Govern
ment “regard[s] the provisions of Article 75 as an articula
tion of safeguards to which all persons in the hands of an
enemy are entitled.” Taft, The Law of Armed Conflict
After 9/11: Some Salient Features, 28 Yale J. Int’l L. 319,
322 (2003). Among the rights set forth in Article 75 is the
“right to be tried in [one’s] presence.” Protocol I, Art.
75(4)(e).66
——————
  65 Further evidence of this tribunal’s irregular constitution is the fact

that its rules and procedures are subject to change midtrial, at the
whim of the Executive. See Commission Order No. 1, §11 (providing
that the Secretary of Defense may change the governing rules “from
time to time”).
  66 Other international instruments to which the United States is a
                      Cite as: 548 U. S. ____ (2006)                     71

                          Opinion of STEVENS, J.

  We agree with JUSTICE KENNEDY that the procedures
adopted to try Hamdan deviate from those governing
courts-martial in ways not justified by any “evident practi
cal need,” post, at 11, and for that reason, at least, fail to
afford the requisite guarantees. See post, at 8, 11–17. We
add only that, as noted in Part VI–A, supra, various provi
sions of Commission Order No. 1 dispense with the princi
ples, articulated in Article 75 and indisputably part of the
customary international law, that an accused must, absent
disruptive conduct or consent, be present for his trial and
must be privy to the evidence against him. See §§6(B)(3),
(D).67 That the Government has a compelling interest in
——————
signatory include the same basic protections set forth in Article 75.
See, e.g., International Covenant on Civil and Political Rights, Art. 14,
¶3(d), Mar. 23, 1976, 999 U. N. T. S. 171 (setting forth the right of an
accused “[t]o be tried in his presence, and to defend himself in person or
through legal assistance of his own choosing”). Following World War II,
several defendants were tried and convicted by military commission for
violations of the law of war in their failure to afford captives fair trials
before imposition and execution of sentence. In two such trials, the
prosecutors argued that the defendants’ failure to apprise accused
individuals of all evidence against them constituted violations of the
law of war. See 5 U. N. War Crimes Commission 30 (trial of Sergeant-
Major Shigeru Ohashi), 75 (trial of General Tanaka Hisakasu).
   67 The Government offers no defense of these procedures other than to

observe that the defendant may not be barred from access to evidence if
such action would deprive him of a “full and fair trial.” Commission
Order No. 1, §6(D)(5)(b). But the Government suggests no circum
stances in which it would be “fair” to convict the accused based on
evidence he has not seen or heard. Cf. Crawford v. Washington, 541
U. S. 36, 49 (2004) (“ ‘It is a rule of the common law, founded on natural
justice, that no man shall be prejudiced by evidence which he had not
the liberty to cross examine’ ” (quoting State v. Webb, 2 N. C. 103, 104
(Super. L. & Eq. 1794) (per curiam)); Diaz v. United States, 223 U. S.
442, 455 (1912) (describing the right to be present as “scarcely less
important to the accused than the right of trial itself”); Lewis v. United
States, 146 U. S. 370, 372 (1892) (exclusion of defendant from part of
proceedings is “contrary to the dictates of humanity” (internal quota
tion marks omitted)); Joint Anti-Fascist Refugee Comm. v. McGrath,
341 U. S. 123, 170, n. 17, 171 (1951) (Frankfurter, J., concurring) (“[t]he
72                    HAMDAN v. RUMSFELD

                         Opinion of the Court

denying Hamdan access to certain sensitive information is
not doubted. Cf. post, at 47–48 (THOMAS, J., dissenting).
But, at least absent express statutory provision to the
contrary, information used to convict a person of a crime
must be disclosed to him.
                             v
   Common Article 3 obviously tolerates a great degree of
flexibility in trying individuals captured during armed
conflict; its requirements are general ones, crafted to
accommodate a wide variety of legal systems. But re
quirements they are nonetheless. The commission that
the President has convened to try Hamdan does not meet
those requirements.
                            VII
  We have assumed, as we must, that the allegations
made in the Government’s charge against Hamdan are
true. We have assumed, moreover, the truth of the mes
sage implicit in that charge—viz., that Hamdan is a dan
gerous individual whose beliefs, if acted upon, would cause
great harm and even death to innocent civilians, and who
would act upon those beliefs if given the opportunity. It
bears emphasizing that Hamdan does not challenge, and
we do not today address, the Government’s power to de
tain him for the duration of active hostilities in order to
prevent such harm. But in undertaking to try Hamdan
and subject him to criminal punishment, the Executive is
bound to comply with the Rule of Law that prevails in this
jurisdiction.
  The judgment of the Court of Appeals is reversed, and
—————— 

plea that evidence of guilt must be secret is abhorrent to free men”

(internal quotation marks omitted)). More fundamentally, the legality

of a tribunal under Common Article 3 cannot be established by bare 

assurances that, whatever the character of the court or the procedures 

it follows, individual adjudicators will act fairly. 

                 Cite as: 548 U. S. ____ (2006)                 73

                     Opinion of the Court

the case is remanded for further proceedings.

                                                  It is so ordered.

  THE CHIEF JUSTICE took no part in the consideration or
decision of this case.
                 Cite as: 548 U. S. ____ (2006)          1

                    BREYER, J., concurring

SUPREME COURT OF THE UNITED STATES
                         _________________

                          No. 05–184
                         _________________


 SALIM AHMED HAMDAN, PETITIONER v. DONALD
  H. RUMSFELD, SECRETARY OF DEFENSE, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

    APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT

                        [June 29, 2006] 


   JUSTICE BREYER, with whom JUSTICE KENNEDY,
JUSTICE SOUTER, and JUSTICE GINSBURG join, concurring.
   The dissenters say that today’s decision would “sorely
hamper the President’s ability to confront and defeat a
new and deadly enemy.” Post, at 29 (opinion of THOMAS,
J.). They suggest that it undermines our Nation’s ability
to “preven[t] future attacks” of the grievous sort that we
have already suffered. Post, at 48. That claim leads me to
state briefly what I believe the majority sets forth both
explicitly and implicitly at greater length. The Court’s
conclusion ultimately rests upon a single ground: Congress
has not issued the Executive a “blank check.” Cf. Hamdi
v. Rumsfeld, 542 U. S. 507, 536 (2004) (plurality opinion).
Indeed, Congress has denied the President the legisla-
tive authority to create military commissions of the kind
at issue here. Nothing prevents the President from re
turning to Congress to seek the authority he believes
necessary.
   Where, as here, no emergency prevents consultation
with Congress, judicial insistence upon that consultation
does not weaken our Nation’s ability to deal with danger.
To the contrary, that insistence strengthens the Nation’s
ability to determine—through democratic means—how
best to do so. The Constitution places its faith in those
democratic means. Our Court today simply does the same.
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                 KENNEDY, J., concurring in part

SUPREME COURT OF THE UNITED STATES
                          _________________

                           No. 05–184
                          _________________


 SALIM AHMED HAMDAN, PETITIONER v. DONALD
  H. RUMSFELD, SECRETARY OF DEFENSE, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

    APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT

                         [June 29, 2006] 


   JUSTICE KENNEDY, with whom JUSTICE SOUTER,
JUSTICE GINSBURG, and JUSTICE BREYER join as to Parts I
and II, concurring in part.
   Military Commission Order No. 1, which governs the
military commission established to try petitioner Salim
Hamdan for war crimes, exceeds limits that certain stat
utes, duly enacted by Congress, have placed on the Presi
dent’s authority to convene military courts. This is not a
case, then, where the Executive can assert some unilateral
authority to fill a void left by congressional inaction. It is
a case where Congress, in the proper exercise of its powers
as an independent branch of government, and as part of a
long tradition of legislative involvement in matters of
military justice, has considered the subject of military
tribunals and set limits on the President’s authority.
Where a statute provides the conditions for the exercise of
governmental power, its requirements are the result of a
deliberative and reflective process engaging both of the
political branches. Respect for laws derived from the
customary operation of the Executive and Legislative
Branches gives some assurance of stability in time of
crisis. The Constitution is best preserved by reliance on
standards tested over time and insulated from the pres
sures of the moment.
   These principles seem vindicated here, for a case that
2                  HAMDAN v. RUMSFELD

                 KENNEDY, J., concurring in part

may be of extraordinary importance is resolved by ordi
nary rules. The rules of most relevance here are those
pertaining to the authority of Congress and the interpre
tation of its enactments.
   It seems appropriate to recite these rather fundamental
points because the Court refers, as it should in its exposi
tion of the case, to the requirement of the Geneva Conven
tions of 1949 that military tribunals be “regularly consti
tuted” ante, at 69—a requirement that controls here, if for
no other reason, because Congress requires that military
commissions like the ones at issue conform to the “law of
war,” 10 U. S. C. §821. Whatever the substance and con
tent of the term “regularly constituted” as interpreted in
this and any later cases, there seems little doubt that it
relies upon the importance of standards deliberated upon
and chosen in advance of crisis, under a system where the
single power of the Executive is checked by other constitu
tional mechanisms. All of which returns us to the point of
beginning—that domestic statutes control this case. If
Congress, after due consideration, deems it appropriate to
change the controlling statutes, in conformance with the
Constitution and other laws, it has the power and preroga
tive to do so.
   I join the Court’s opinion, save Parts V and VI–D–iv. To
state my reasons for this reservation, and to show my
agreement with the remainder of the Court’s analysis by
identifying particular deficiencies in the military commis
sions at issue, this separate opinion seems appropriate.
                              I
  Trial by military commission raises separation-of
powers concerns of the highest order. Located within a
single branch, these courts carry the risk that offenses will
be defined, prosecuted, and adjudicated by executive
officials without independent review. Cf. Loving v. United
States, 517 U. S. 748, 756–758, 760 (1996). Concentration of
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                 KENNEDY, J., concurring in part

power puts personal liberty in peril of arbitrary action by
officials, an incursion the Constitution’s three-part system is
designed to avoid. It is imperative, then, that when military
tribunals are established, full and proper authority exists
for the Presidential directive.
   The proper framework for assessing whether Executive
actions are authorized is the three-part scheme used by
Justice Jackson in his opinion in Youngstown Sheet & Tube
Co. v. Sawyer, 343 U. S. 579 (1952). “When the President
acts pursuant to an express or implied authorization of
Congress, his authority is at its maximum, for it includes all
that he possesses in his own right plus all that Congress can
delegate.” Id., at 635. “When the President acts in absence
of either a congressional grant or denial of authority, he can
only rely upon his own independent powers, but there is a
zone of twilight in which he and Congress may have concur
rent authority, or in which its distribution is uncertain.”
Id., at 637. And “[w]hen the President takes measures
incompatible with the expressed or implied will of Congress,
his power is at its lowest ebb.” Ibid.
   In this case, as the Court observes, the President has
acted in a field with a history of congressional participa
tion and regulation. Ante, at 28–30, 55–57. In the Uni
form Code of Military Justice (UCMJ), 10 U. S. C. §801 et
seq., which Congress enacted, building on earlier statutes,
in 1950, see Act of May 5, 1950, ch. 169, 64 Stat. 107, and
later amended, see, e.g., Military Justice Act of 1968, 82
Stat. 1335, Congress has set forth governing principles for
military courts. The UCMJ as a whole establishes an
intricate system of military justice. It authorizes courts-
martial in various forms, 10 U. S. C. §§816–820 (2000 ed.
and Supp. III); it regulates the organization and procedure
of those courts, e.g., §§822–835, 851–854; it defines of
fenses, §§877–934, and rights for the accused, e.g.,
§§827(b)–(c), 831, 844, 846, 855 (2000 ed.); and it provides
mechanisms for appellate review, §§859–876b (2000 ed.
4                  HAMDAN v. RUMSFELD

                KENNEDY, J., concurring in part

and Supp. III). As explained below, the statute further
recognizes that special military commissions may be
convened to try war crimes. See infra, at 5–6; §821 (2000
ed.). While these laws provide authority for certain forms
of military courts, they also impose limitations, at least
two of which control this case. If the President has ex
ceeded these limits, this becomes a case of conflict between
Presidential and congressional action—a case within
Justice Jackson’s third category, not the second or first.
  One limit on the President’s authority is contained in
§836 of the UCMJ. That section provides:
    “(a) Pretrial, trial, and post-trial procedures, including
    modes of proof, for cases arising under this chapter
    triable in courts-martial, military commissions and
    other military tribunals, and procedures for courts of
    inquiry, may be prescribed by the President by regu
    lations which shall, so far as he considers practicable,
    apply the principles of law and the rules of evidence
    generally recognized in the trial of criminal cases in
    the United States district courts, but which may not
    be contrary to or inconsistent with this chapter.
    “(b) All rules and regulations made under this article
    shall be uniform insofar as practicable.” 10 U. S. C.
    §836 (2000 ed.).
In this provision the statute allows the President to im
plement and build on the UCMJ’s framework by adopting
procedural regulations, subject to three requirements: (1)
Procedures for military courts must conform to district-
court rules insofar as the President “considers practica
ble”; (2) the procedures may not be contrary to or inconsis
tent with the provisions of the UCMJ; and (3) “insofar as
practicable” all rules and regulations under §836 must be
uniform, a requirement, as the Court points out, that
indicates the rules must be the same for military commis
sions as for courts-martial unless such uniformity is im
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                 KENNEDY, J., concurring in part

practicable, ante, at 57, 59, and n. 50.
   As the Court further instructs, even assuming the first
and second requirements of §836 are satisfied here—a
matter of some dispute, see ante, at 57–59—the third
requires us to compare the military-commission proce
dures with those for courts-martial and determine, to the
extent there are deviations, whether greater uniformity
would be practicable. Ante, at 59–62. Although we can
assume the President’s practicability judgments are enti
tled to some deference, the Court observes that Congress’
choice of language in the uniformity provision of 10
U. S. C. §836(b) contrasts with the language of §836(a).
This difference suggests, at the least, a lower degree of
deference for §836(b) determinations. Ante, at 59–60. The
rules for military courts may depart from federal-court
rules whenever the President “considers” conformity im
practicable, §836(a); but the statute requires procedural
uniformity across different military courts “insofar as
[uniformity is] practicable,” §836(b), not insofar as the
President considers it to be so. The Court is right to con
clude this is of relevance to our decision. Further, as the
Court is also correct to conclude, ante, at 60, the term
“practicable” cannot be construed to permit deviations
based on mere convenience or expedience. “Practicable”
means “feasible,” that is, “possible to practice or perform”
or “capable of being put into practice, done, or accom
plished.” Webster’s Third New International Dictionary
1780 (1961). Congress’ chosen language, then, is best
understood to allow the selection of procedures based on
logistical constraints, the accommodation of witnesses, the
security of the proceedings, and the like. Insofar as the
“[p]retrial, trial, and post-trial procedures” for the military
commissions at issue deviate from court-martial practice,
the deviations must be explained by some such practical
need.
   In addition to §836, a second UCMJ provision, 10
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                 KENNEDY, J., concurring in part

U. S. C. §821, requires us to compare the commissions at
issue to courts-martial. This provision states:
    “The provisions of this chapter conferring jurisdiction
    upon courts-martial do not deprive military commis
    sions, provost courts, or other military tribunals of
    concurrent jurisdiction with respect to offenders or of
    fenses that by statute or by the law of war may be
    tried by military commissions, provost courts, or other
    military tribunals.”
   In §821 Congress has addressed the possibility that
special military commissions—criminal courts other than
courts-martial—may at times be convened. At the same
time, however, the President’s authority to convene mili
tary commissions is limited: It extends only to “offenders
or offenses” that “by statute or by the law of war may be
tried by” such military commissions. Ibid.; see also ante,
at 28–29. The Government does not claim to base the
charges against Hamdan on a statute; instead it invokes
the law of war. That law, as the Court explained in Ex
parte Quirin, 317 U. S. 1 (1942), derives from “rules and
precepts of the law of nations”; it is the body of international
law governing armed conflict. Id., at 28. If the military
commission at issue is illegal under the law of war, then
an offender cannot be tried “by the law of war” before that
commission.
   The Court is correct to concentrate on one provision of
the law of war that is applicable to our Nation’s armed
conflict with al Qaeda in Afghanistan and, as a result, to
the use of a military commission to try Hamdan. Ante, at
65–70; see also 415 F. 3d 33, 44 (CADC 2005) (Williams,
J., concurring). That provision is Common Article 3 of the
four Geneva Conventions of 1949. It prohibits, as relevant
here, “[t]he passing of sentences and the carrying out of
executions without previous judgment pronounced by a
regularly constituted court affording all the judicial guar
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                 KENNEDY, J., concurring in part

antees which are recognized as indispensable by civilized
peoples.” See, e.g., Article 3 of the Geneva Convention
(III) Relative to the Treatment of Prisoners of War, Aug.
12, 1949, [1955] 6 U. S. T. 3316, 3318, T. I. A. S. No. 3364.
The provision is part of a treaty the United States has
ratified and thus accepted as binding law. See id., at
3316. By Act of Congress, moreover, violations of Common
Article 3 are considered “war crimes,” punishable as fed
eral offenses, when committed by or against United States
nationals and military personnel. See 18 U. S. C. §2441.
There should be no doubt, then, that Common Article 3 is
part of the law of war as that term is used in §821.
   The dissent by JUSTICE THOMAS argues that Common
Article 3 nonetheless is irrelevant to this case because in
Johnson v. Eisentrager, 339 U. S. 763 (1950), it was said to
be the “obvious scheme” of the 1929 Geneva Convention
that “[r]ights of alien enemies are vindicated under it only
through protests and intervention of protecting powers,”
i.e., signatory states, id., at 789, n. 14. As the Court ex
plains, ante, at 63–65, this language from Eisentrager is
not controlling here. Even assuming the Eisentrager
analysis has some bearing upon the analysis of the
broader 1949 Conventions and that, in consequence, rights
are vindicated “under [those Conventions]” only through
protests and intervention, 339 U. S., at 789, n. 14, Com
mon Article 3 is nonetheless relevant to the question of
authorization under §821. Common Article 3 is part of the
law of war that Congress has directed the President to
follow in establishing military commissions. Ante, at 66–
67. Consistent with that view, the Eisentrager Court itself
considered on the merits claims that “procedural irregu
larities” under the 1929 Convention “deprive[d] the Mili
tary Commission of jurisdiction.” 339 U. S., at 789, 790.
   In another military commission case, In re Yamashita,
327 U. S. 1 (1946), the Court likewise considered on the
merits—without any caveat about remedies under the
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                KENNEDY, J., concurring in part

Convention—a claim that an alleged violation of the 1929
Convention “establish[ed] want of authority in the com
mission to proceed with the trial.” Id., at 23, 24. That is
the precise inquiry we are asked to perform here.
   Assuming the President has authority to establish a
special military commission to try Hamdan, the commis
sion must satisfy Common Article 3’s requirement of a
“regularly constituted court affording all the judicial guar
antees which are recognized as indispensable by civilized
peoples,” 6 U. S. T., at 3318. The terms of this general
standard are yet to be elaborated and further defined, but
Congress has required compliance with it by referring to
the “law of war” in §821. The Court correctly concludes
that the military commission here does not comply with
this provision.
   Common Article 3’s standard of a “regularly constituted
court affording all the judicial guarantees which are rec
ognized as indispensable by civilized peoples,” ibid., sup
ports, at the least, a uniformity principle similar to that
codified in §836(b). The concept of a “regularly constituted
court” providing “indispensable” judicial guarantees re
quires consideration of the system of justice under which
the commission is established, though no doubt certain
minimum standards are applicable. See ante, at 69–70; 1
Int’l Committee of the Red Cross, Customary Interna
tional Humanitarian Law 355 (2005) (explaining that
courts are “regularly constituted” under Common Article 3
if they are “established and organised in accordance with
the laws and procedures already in force in a country”).
   The regular military courts in our system are the courts-
martial established by congressional statutes. Acts of
Congress confer on those courts the jurisdiction to try “any
person” subject to war crimes prosecution. 10 U. S. C.
§818. As the Court explains, moreover, while special
military commissions have been convened in previous
armed conflicts—a practice recognized in §821—those
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                 KENNEDY, J., concurring in part

military commissions generally have adopted the struc
ture and procedure of courts-martial. See, e.g., 1 The War
of the Rebellion: A Compilation of the Official Records of
the Union and Confederate Armies 248 (2d series 1894)
(Civil War general order requiring that military commis
sions “be constituted in a similar manner and their pro
ceedings be conducted according to the same general rules
as courts-martial in order to prevent abuses which might
otherwise arise”); W. Winthrop, Military Law and Prece
dents 835, n. 81 (rev. 2d ed. 1920) (“[M]ilitary commissions
are constituted and composed, and their proceedings are
conducted, similarly to general courts-martial”); 1 United
Nations War Crimes Commission, Law Reports of Trials of
War Criminals 116–117 (1947) (reprint 1997) (hereinafter
Law Reports) (discussing post-World War II regulations
requiring that military commissions “hav[e] regard for”
rules of procedure and evidence applicable in general
courts-martial); see also ante, at 53–57; post, at 31, n. 15
(THOMAS, J., dissenting). Today, moreover, §836(b)—
which took effect after the military trials in the World War
II cases invoked by the dissent, see Madsen v. Kinsella, 343
U. S. 341, 344–345, and n. 6 (1952); Yamashita, supra, at 5;
Quirin, 317 U. S., at 23—codifies this presumption of uni
formity at least as to “[p]retrial, trial, and post-trial proce
dures.” Absent more concrete statutory guidance, this
historical and statutory background—which suggests that
some practical need must justify deviations from the
court-martial model—informs the understanding of which
military courts are “regularly constituted” under United
States law.
   In addition, whether or not the possibility, contemplated
by the regulations here, of midtrial procedural changes
could by itself render a military commission impermissibly
irregular, ante, at 70, n. 65; see also Military Commission
Order No. 1, §11 (Aug. 31, 2005), App. to Brief for Peti
tioner 46a–72a (hereinafter MCO), an acceptable degree of
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                 KENNEDY, J., concurring in part

independence from the Executive is necessary to render a
commission “regularly constituted” by the standards of our
Nation’s system of justice. And any suggestion of Execu
tive power to interfere with an ongoing judicial process
raises concerns about the proceedings’ fairness. Again,
however, courts-martial provide the relevant benchmark.
Subject to constitutional limitations, see Ex parte Milligan,
4 Wall. 2 (1866), Congress has the power and responsibility
to determine the necessity for military courts, and to
provide the jurisdiction and procedures applicable to them.
The guidance Congress has provided with respect to
courts-martial indicates the level of independence and
procedural rigor that Congress has deemed necessary, at
least as a general matter, in the military context.
   At a minimum a military commission like the one at
issue—a commission specially convened by the President
to try specific persons without express congressional au
thorization—can be “regularly constituted” by the stan
dards of our military justice system only if some practical
need explains deviations from court-martial practice. In
this regard the standard of Common Article 3, applied
here in conformity with §821, parallels the practicability
standard of §836(b). Section 836, however, is limited by
its terms to matters properly characterized as proce
dural—that is, “[p]retrial, trial, and post-trial proce
dures”—while Common Article 3 permits broader consid
eration of matters of structure, organization, and
mechanisms to promote the tribunal’s insulation from
command influence. Thus the combined effect of the two
statutes discussed here—§§836 and 821—is that consid
erations of practicability must support departures from
court-martial practice. Relevant concerns, as noted ear
lier, relate to logistical constraints, accommodation of
witnesses, security of the proceedings, and the like, not
mere expedience or convenience. This determination, of
course, must be made with due regard for the constitu
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                KENNEDY, J., concurring in part

tional principle that congressional statutes can be control
ling, including the congressional direction that the law of
war has a bearing on the determination.
   These principles provide the framework for an analysis
of the specific military commission at issue here.
                              II
   In assessing the validity of Hamdan’s military commis
sion the precise circumstances of this case bear emphasis.
The allegations against Hamdan are undoubtedly serious.
Captured in Afghanistan during our Nation’s armed con
flict with the Taliban and al Qaeda—a conflict that con
tinues as we speak—Hamdan stands accused of overt acts
in furtherance of a conspiracy to commit terrorism: deliv
ering weapons and ammunition to al Qaeda, acquiring
trucks for use by Osama bin Laden’s bodyguards, provid
ing security services to bin Laden, and receiving weapons
training at a terrorist camp. App. to Pet. for Cert. 65a–
67a. Nevertheless, the circumstances of Hamdan’s trial
present no exigency requiring special speed or precluding
careful consideration of evidence. For roughly four years,
Hamdan has been detained at a permanent United States
military base in Guantanamo Bay, Cuba. And regardless
of the outcome of the criminal proceedings at issue, the
Government claims authority to continue to detain him
based on his status as an enemy combatant.
   Against this background, the Court is correct to con
clude that the military commission the President has
convened to try Hamdan is unauthorized. Ante, at 62, 69–
70, 72. The following analysis, which expands on the
Court’s discussion, explains my reasons for reaching this
conclusion.
   To begin with, the structure and composition of the
military commission deviate from conventional court-
martial standards. Although these deviations raise ques
tions about the fairness of the trial, no evident practical
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                 KENNEDY, J., concurring in part

need explains them.
   Under the UCMJ, courts-martial are organized by a
“convening authority”—either a commanding officer, the
Secretary of Defense, the Secretary concerned, or the
President. 10 U. S. C. §§822–824 (2000 ed. and Supp. III).
The convening authority refers charges for trial, Manual
for Courts-Martial, United States, Rule for Courts-Martial
401 (2005 ed.) (hereinafter R. C. M.), and selects the court-
martial members who vote on the guilt or innocence of the
accused and determine the sentence, 10 U. S. C.
§§825(d)(2), 851–852 (2000 ed.); R. C. M. 503(a). Parallel
ing this structure, under Military Commission Order No. 1
an “ ‘Appointing Authority’ ”—either the Secretary of De
fense or the Secretary’s “designee”—establishes commis
sions subject to the order, MCO No. 1, §2, approves and
refers charges to be tried by those commissions,
§4(B)(2)(a), and appoints commission members who vote
on the conviction and sentence, §§4(A)(1–3). In addition
the Appointing Authority determines the number of com
mission members (at least three), oversees the chief prose
cutor, provides “investigative or other resources” to the
defense insofar as he or she “deems necessary for a full
and fair trial,” approves or rejects plea agreements, ap
proves or disapproves communications with news media
by prosecution or defense counsel (a function shared by
the General Counsel of the Department of Defense), and
issues supplementary commission regulations (subject to
approval by the General Counsel of the Department of
Defense, unless the Appointing Authority is the Secretary
of Defense). See MCO No. 1, §§4(A)(2), 5(H), 6(A)(4), 7(A);
Military Commission Instruction No. 3, §5(C) (July 15,
2005)     (hereinafter    MCI),    available     at    www.
defenselink.mil/news/Aug2005/d20050811MC13.pdf; MCI
No. 4, §5(C) (Sept. 16, 2005), available at www.
defenselink.mil/news/Oct2005/d20051003MCI4.pdf          MCI
No. 6, §3(B)(3) (April 15, 2004), available at www.
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                 KENNEDY, J., concurring in part

defenselink.mil/news/Apr2004/d20040420ins6.pdf (all In
ternet materials as visited June 27, 2006, and available in
Clerk of Court’s case file).
  Against the background of these significant powers for
the Appointing Authority, which in certain respects at
least conform to ordinary court-martial standards, the
regulations governing the commissions at issue make
several noteworthy departures.        At a general court-
martial—the only type authorized to impose penalties of
more than one year’s incarceration or to adjudicate of
fenses against the law of war, R. C. M. 201(f); 10 U. S. C.
§§818–820 (2000 ed. and Supp. III)—the presiding officer
who rules on legal issues must be a military judge.
R. C. M. 501(a)(1), 801(a)(4)–(5); 10 U. S. C. §816(1) (2000
ed., Supp. III); see also R. C. M. 201(f)(2)(B)(ii) (likewise
requiring a military judge for certain other courts-
martial); 10 U. S. C. §819 (2000 ed. and Supp. III) (same).
A military judge is an officer who is a member of a state or
federal bar and has been specially certified for judicial
duties by the Judge Advocate General for the officer’s
Armed Service. R. C. M. 502(c); 10 U. S. C. §826(b). To
protect their independence, military judges at general
courts-martial are “assigned and directly responsible to
the Judge Advocate General or the Judge Advocate Gen
eral’s designee.” R. C. M. 502(c). They must be detailed to
the court, in accordance with applicable regulations, “by a
person assigned as a military judge and directly responsi
ble to the Judge Advocate General or the Judge Advocate
General’s designee.” R. C. M. 503(b); see also 10 U. S. C.
§826(c); see generally Weiss v. United States, 510 U. S. 163,
179–181 (1994) (discussing provisions that “insulat[e] mili
tary judges from the effects of command influence” and thus
“preserve judicial impartiality”). Here, by contrast, the
Appointing Authority selects the presiding officer, MCO
No. 1, §§4(A)(1), (A)(4); and that officer need only be a
judge advocate, that is, a military lawyer, §4(A)(4).
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                 KENNEDY, J., concurring in part

   The Appointing Authority, moreover, exercises supervi
sory powers that continue during trial. Any interlocutory
question “the disposition of which would effect a termina
tion of proceedings with respect to a charge” is subject to
decision not by the presiding officer, but by the Appointing
Authority. §4(A)(5)(e) (stating that the presiding officer
“shall certify” such questions to the Appointing Authority).
Other interlocutory questions may be certified to the
Appointing Authority as the presiding officer “deems
appropriate.” Ibid. While in some circumstances the
Government may appeal certain rulings at a court-
martial—including “an order or ruling that terminates the
proceedings with respect to a charge or specification,”
R. C. M. 908(a); see also 10 U. S. C. §862(a)—the appeals
go to a body called the Court of Criminal Appeals, not to
the convening authority. R. C. M. 908; 10 U. S. C. §862(b);
see also R. C. M. 1107 (requiring the convening authority
to approve or disapprove the findings and sentence of a
court-martial but providing for such action only after
entry of sentence and restricting actions that increase
penalties); 10 U. S. C. §860 (same); cf. §837(a) (barring
command influence on court-martial actions). The Court
of Criminal Appeals functions as the military’s intermedi
ate appeals court; it is established by the Judge Advocate
General for each Armed Service and composed of appellate
military judges. R. C. M. 1203; 10 U. S. C. §866. This is
another means in which, by structure and tradition, the
court-martial process is insulated from those who have an
interest in the outcome of the proceedings.
   Finally, in addition to these powers with respect to the
presiding officer, the Appointing Authority has greater
flexibility in appointing commission members. While a
general court-martial requires, absent a contrary election
by the accused, at least five members, R. C. M. 501(a)(1);
10 U. S. C. §816(1) (2000 ed. and Supp. III), the Appoint
ing Authority here is free, as noted earlier, to select as few
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                 KENNEDY, J., concurring in part

as three. MCO No. 1, §4(A)(2). This difference may affect
the deliberative process and the prosecution’s burden of
persuasion.
   As compared to the role of the convening authority in a
court-martial, the greater powers of the Appointing Au
thority here—including even the resolution of dispositive
issues in the middle of the trial—raise concerns that the
commission’s decisionmaking may not be neutral. If the
differences are supported by some practical need beyond
the goal of constant and ongoing supervision, that need is
neither apparent from the record nor established by the
Government’s submissions.
   It is no answer that, at the end of the day, the Detainee
Treatment Act of 2005 (DTA), 119 Stat. 2739, affords
military-commission defendants the opportunity for judi
cial review in federal court. As the Court is correct to
observe, the scope of that review is limited, DTA
§1005(e)(3)(D), id., at 2743; see also ante, at 8–9, and the
review is not automatic if the defendant’s sentence is
under 10 years, §1005(e)(3)(B), ibid. Also, provisions for
review of legal issues after trial cannot correct for struc
tural defects, such as the role of the Appointing Authority,
that can cast doubt on the factfinding process and the
presiding judge’s exercise of discretion during trial. Before
military-commission defendants may obtain judicial re
view, furthermore, they must navigate a military review
process that again raises fairness concerns. At the outset,
the Appointing Authority (unless the Appointing Author
ity is the Secretary of Defense) performs an “administra
tive review” of undefined scope, ordering any “supplemen
tary proceedings” deemed necessary. MCO No. 1 §6(H)(3).
After that the case is referred to a three-member
Review Panel composed of officers selected by the
Secretary of Defense. §6(H)(4); MCI No. 9, §4(B) (Oct. 11,
2005), available at www.defenselink.mil/news/Oct2005/
d20051014MCI9.pdf.        Though the Review Panel may
16                 HAMDAN v. RUMSFELD

                KENNEDY, J., concurring in part

return the case for further proceedings only if a majority
“form[s] a definite and firm conviction that a material
error of law occurred,” MCO No. 1, §6(H)(4); MCI No. 9,
§4(C)(1)(a), only one member must have “experience as a
judge,” MCO No. 1, §6(H)(4); nothing in the regulations
requires that other panel members have legal training.
By comparison to the review of court-martial judgments
performed by such independent bodies as the Judge Advo
cate General, the Court of Criminal Appeals, and the
Court of Appeals for the Armed Forces, 10 U. S. C. §§862,
864, 866, 867, 869, the review process here lacks struc
tural protections designed to help ensure impartiality.
   These structural differences between the military com
missions and courts-martial—the concentration of func
tions, including legal decisionmaking, in a single executive
official; the less rigorous standards for composition of the
tribunal; and the creation of special review procedures in
place of institutions created and regulated by Congress—
remove safeguards that are important to the fairness of
the proceedings and the independence of the court. Con
gress has prescribed these guarantees for courts-martial;
and no evident practical need explains the departures
here. For these reasons the commission cannot be consid
ered regularly constituted under United States law and
thus does not satisfy Congress’ requirement that military
commissions conform to the law of war.
   Apart from these structural issues, moreover, the basic
procedures for the commissions deviate from procedures
for courts-martial, in violation of §836(b). As the Court
explains, ante, at 51, 61, the Military Commission Order
abandons the detailed Military Rules of Evidence, which
are modeled on the Federal Rules of Evidence in confor
mity with §836(a)’s requirement of presumptive compli
ance with district-court rules.
   Instead, the order imposes just one evidentiary rule:
“Evidence shall be admitted if . . . the evidence would have
                 Cite as: 548 U. S. ____ (2006)         17

                KENNEDY, J., concurring in part

probative value to a reasonable person,” MCO No. 1,
§6(D)(1). Although it is true some military commissions
applied an amorphous evidence standard in the past, see,
e.g., 1 Law Reports 117–118 (discussing World War II
military commission orders); Exec. Order No. 9185, 7 Fed.
Reg. 5103 (1942) (order convening military commission to
try Nazi saboteurs), the evidentiary rules for those com
missions were adopted before Congress enacted the uni
formity requirement of 10 U. S. C. §836(b) as part of the
UCMJ, see Act of May 5, 1950, ch. 169, 64 Stat. 107, 120,
149. And while some flexibility may be necessary to per
mit trial of battlefield captives like Hamdan, military
statutes and rules already provide for introduction of
deposition testimony for absent witnesses, 10 U. S. C.
§849(d); R. C. M. 702, and use of classified information,
Military Rule Evid. 505. Indeed, the deposition-testimony
provision specifically mentions military commissions and
thus is one of the provisions the Government concedes
must be followed by the commission at issue. See ante, at
58. That provision authorizes admission of deposition
testimony only if the witness is absent for specified rea
sons, §849(d)—a requirement that makes no sense if
military commissions may consider all probative evidence.
Whether or not this conflict renders the rules at issue
“contrary to or inconsistent with” the UCMJ under
§836(a), it creates a uniformity problem under §836(b).
   The rule here could permit admission of multiple hear
say and other forms of evidence generally prohibited on
grounds of unreliability. Indeed, the commission regula
tions specifically contemplate admission of unsworn writ
ten statements, MCO No. 1, §6(D)(3); and they make no
provision for exclusion of coerced declarations save those
“established to have been made as a result of torture,”
MCI No. 10, §3(A) (Mar. 24, 2006), available at www.
defenselink.mil/news/Mar2006/d20060327MCI10.pdf; cf.
Military Rule Evid. 304(c)(3) (generally barring use of
18                 HAMDAN v. RUMSFELD

                KENNEDY, J., concurring in part

statements obtained “through the use of coercion, unlaw
ful influence, or unlawful inducement”); 10 U. S. C.
§831(d) (same). Besides, even if evidence is deemed non-
probative by the presiding officer at Hamdan’s trial, the
military-commission members still may view it. In an
other departure from court-martial practice the military
commission members may object to the presiding officer’s
evidence rulings and determine themselves, by majority
vote, whether to admit the evidence. MCO No. 1, §6(D)(1);
cf. R. C. M. 801(a)(4), (e)(1) (providing that the military
judge at a court-martial determines all questions of law).
   As the Court explains, the Government has made no
demonstration of practical need for these special rules and
procedures, either in this particular case or as to the
military commissions in general, ante, at 59–61; nor is any
such need self-evident. For all the Government’s regula
tions and submissions reveal, it would be feasible for most,
if not all, of the conventional military evidence rules and
procedures to be followed.
   In sum, as presently structured, Hamdan’s military
commission exceeds the bounds Congress has placed on
the President’s authority in §§836 and 821 of the UCMJ.
Because Congress has prescribed these limits, Congress
can change them, requiring a new analysis consistent with
the Constitution and other governing laws. At this time,
however, we must apply the standards Congress has
provided. By those standards the military commission is
deficient.
                            III
  In light of the conclusion that the military commission
here is unauthorized under the UCMJ, I see no need to
consider several further issues addressed in the plurality
opinion by JUSTICE STEVENS and the dissent by JUSTICE
THOMAS.
  First, I would not decide whether Common Article 3’s
                 Cite as: 548 U. S. ____ (2006)           19

                 KENNEDY, J., concurring in part

standard—a “regularly constituted court affording all the
judicial guarantees which are recognized as indispensable
by civilized peoples,” 6 U. S. T., at 3320 (¶(1)(d))—
necessarily requires that the accused have the right to be
present at all stages of a criminal trial. As JUSTICE
STEVENS explains, Military Commission Order No. 1
authorizes exclusion of the accused from the proceedings if
the presiding officer determines that, among other things,
protection of classified information so requires.         See
§§6(B)(3), (D)(5); ante, at 50. JUSTICE STEVENS observes
that these regulations create the possibility of a conviction
and sentence based on evidence Hamdan has not seen or
heard—a possibility the plurality is correct to consider
troubling. Ante, at 71–72, n. 67 (collecting cases); see also
In re Oliver, 333 U. S. 257, 277 (1948) (finding “no support
for sustaining petitioner’s conviction of contempt of court
upon testimony given in petitioner’s absence”).
  As the dissent by JUSTICE THOMAS points out, however,
the regulations bar the presiding officer from admitting
secret evidence if doing so would deprive the accused of a
“full and fair trial.” MCO No. 1, §6(D)(5)(b); see also post,
at 47. This fairness determination, moreover, is unambi
guously subject to judicial review under the DTA. See
§1005(e)(3)(D)(i), 119 Stat. 2743 (allowing review of com
pliance with the “standards and procedures” in Military
Commission Order No. 1). The evidentiary proceedings at
Hamdan’s trial have yet to commence, and it remains to be
seen whether he will suffer any prejudicial exclusion.
  There should be reluctance, furthermore, to reach un
necessarily the question whether, as the plurality seems to
conclude, ante, at 70, Article 75 of Protocol I to the Geneva
Conventions is binding law notwithstanding the earlier
decision by our Government not to accede to the Protocol.
For all these reasons, and without detracting from the
importance of the right of presence, I would rely on other
deficiencies noted here and in the opinion by the Court—
20                HAMDAN v. RUMSFELD

                KENNEDY, J., concurring in part

deficiencies that relate to the structure and procedure of
the commission and that inevitably will affect the proceed
ings—as the basis for finding the military commissions
lack authorization under 10 U. S. C. §836 and fail to be
regularly constituted under Common Article 3 and §821.
  I likewise see no need to address the validity of the
conspiracy charge against Hamdan—an issue addressed at
length in Part V of JUSTICE STEVENS’ opinion and in Part
II–C of JUSTICE THOMAS’ dissent. See ante, at 36–49; post,
at 12–28. In light of the conclusion that the military
commissions at issue are unauthorized Congress may
choose to provide further guidance in this area. Congress,
not the Court, is the branch in the better position to un
dertake the “sensitive task of establishing a principle not
inconsistent with the national interest or international
justice.” Banco Nacional de Cuba v. Sabbatino, 376 U. S.
398, 428 (1964).
  Finally, for the same reason, I express no view on the
merits of other limitations on military commissions de
scribed as elements of the common law of war in Part V of
JUSTICE STEVENS’ opinion. See ante, at 31–36, 48–49; post,
at 6–12.
  With these observations I join the Court’s opinion with
the exception of Parts V and VI–D–iv.
                 Cite as: 548 U. S. ____ (2006)           1

                     SCALIA, J., dissenting

SUPREME COURT OF THE UNITED STATES
                         _________________

                          No. 05–184
                         _________________


 SALIM AHMED HAMDAN, PETITIONER v. DONALD
  H. RUMSFELD, SECRETARY OF DEFENSE, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

    APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT

                        [June 29, 2006] 


   JUSTICE SCALIA, with whom JUSTICE THOMAS and
JUSTICE ALITO join, dissenting.
   On December 30, 2005, Congress enacted the Detainee
Treatment Act (DTA). It unambiguously provides that, as
of that date, “no court, justice, or judge” shall have juris
diction to consider the habeas application of a Guan
tanamo Bay detainee. Notwithstanding this plain direc
tive, the Court today concludes that, on what it calls the
statute’s most natural reading, every “court, justice, or
judge” before whom such a habeas application was pend
ing on December 30 has jurisdiction to hear, consider, and
render judgment on it. This conclusion is patently errone
ous. And even if it were not, the jurisdiction supposedly
retained should, in an exercise of sound equitable discre
tion, not be exercised.
                             I

                            A

  The DTA provides: “[N]o court, justice, or judge shall
have jurisdiction to hear or consider an application for a
writ of habeas corpus filed by or on behalf of an alien
detained by the Department of Defense at Guantanamo
Bay, Cuba.” §1005(e)(1), 119 Stat. 2742 (internal division
omitted). This provision “t[ook] effect on the date of the
enactment of this Act,” §1005(h)(1), id., at 2743, which was
2                  HAMDAN v. RUMSFELD

                     SCALIA, J., dissenting

December 30, 2005. As of that date, then, no court had
jurisdiction to “hear or consider” the merits of petitioner’s
habeas application. This repeal of jurisdiction is simply
not ambiguous as between pending and future cases. It
prohibits any exercise of jurisdiction, and it became effec
tive as to all cases last December 30. It is also perfectly
clear that the phrase “no court, justice, or judge” includes
this Court and its Members, and that by exercising our
appellate jurisdiction in this case we are “hear[ing] or
consider[ing] . . . an application for a writ of habeas
corpus.”
   An ancient and unbroken line of authority attests that
statutes ousting jurisdiction unambiguously apply to cases
pending at their effective date. For example, in Bruner v.
United States, 343 U. S. 112 (1952), we granted certiorari
to consider whether the Tucker Act’s provision denying
district court jurisdiction over suits by “officers” of the
United States barred a suit by an employee of the United
States. After we granted certiorari, Congress amended
the Tucker Act by adding suits by “ ‘employees’ ” to the
provision barring jurisdiction over suits by officers. Id., at
114. This statute narrowing the jurisdiction of the district
courts “became effective” while the case was pending
before us, ibid., and made no explicit reference to pending
cases. Because the statute “did not reserve jurisdiction
over pending cases,” id., at 115, we held that it clearly
ousted jurisdiction over them. Summarizing centuries of
practice, we said: “This rule—that, when a law conferring
jurisdiction is repealed without any reservation as to
pending cases, all cases fall with the law—has been ad
hered to consistently by this Court.” Id., at 116–117. See
also Landgraf v. USI Film Products, 511 U. S. 244, 274
(1994) (opinion for the Court by STEVENS, J.) (“We have
regularly applied intervening statutes conferring or oust
ing jurisdiction, whether or not jurisdiction lay when the
underlying conduct occurred or when the suit was filed”).
                 Cite as: 548 U. S. ____ (2006)           3

                     SCALIA, J., dissenting

  This venerable rule that statutes ousting jurisdiction
terminate jurisdiction in pending cases is not, as today’s
opinion for the Court would have it, a judge-made “pre
sumption against jurisdiction,” ante, at 11, that we have
invented to resolve an ambiguity in the statutes. It is
simple recognition of the reality that the plain import of a
statute repealing jurisdiction is to eliminate the power to
consider and render judgment—in an already pending
case no less than in a case yet to be filed.
    “Without jurisdiction the court cannot proceed at all
    in any cause. Jurisdiction is power to declare the law,
    and when it ceases to exist, the only function remain
    ing to the court is that of announcing the fact and
    dismissing the cause. And this is not less clear upon
    authority than upon principle.” Ex parte McCardle,
    7 Wall. 506, 514 (1869) (emphasis added).
  To alter this plain meaning, our cases have required an
explicit reservation of pending cases in the jurisdiction-
repealing statute. For example, Bruner, as mentioned,
looked to whether Congress made “any reservation as to
pending cases.” 343 U. S., at 116–117; see also id., at 115
(“Congress made no provision for cases pending at the
effective date of the Act withdrawing jurisdiction and, for
this reason, Courts of Appeals ordered pending cases
terminated for want of jurisdiction”). Likewise, in Hallo
well v. Commons, 239 U. S. 506 (1916), Justice Holmes
relied on the fact that the jurisdiction-ousting provision
“made no exception for pending litigation, but purported to
be universal,” id., at 508. And in Insurance Co. v. Ritchie,
5 Wall. 541 (1867), we again relied on the fact that the
jurisdictional repeal was made “without any saving of
such causes as that before us,” id., at 544. As in Bruner,
Hallowell, and Ritchie, the DTA’s directive that “no court,
justice, or judge shall have jurisdiction,” §1005(e)(1), 119
Stat. 2742, is made “without any reservation as to pending
4                  HAMDAN v. RUMSFELD

                     SCALIA, J., dissenting

cases” and “purport[s] to be universal.” What we stated in
an earlier case remains true here: “[W]hen, if it had been
the intention to confine the operation of [the jurisdictional
repeal] . . . to cases not pending, it would have been so
easy to have said so, we must presume that Congress
meant the language employed should have its usual and
ordinary signification, and that the old law should be
unconditionally repealed.” Railroad Co. v. Grant, 98 U. S.
398, 403 (1879).
   The Court claims that I “rea[d] too much into” the
Bruner line of cases, ante, at 12, n. 7, and that “the Bruner
rule” has never been “an inflexible trump,” ante, at 19.
But the Court sorely misdescribes Bruner—as if it were a
kind of early-day Lindh v. Murphy, 521 U. S. 320 (1997),
resolving statutory ambiguity by oblique negative infer
ence. On the contrary, as described above, Bruner stated
its holding as an unqualified “rule,” which “has been ad
hered to consistently by this Court.” 343 U. S., at 116–
117. Though Bruner referred to an express savings clause
elsewhere in the statute, id., at 115, n. 7, it disavowed any
reliance on such oblique indicators to vary the plain mean
ing, quoting Ritchie at length: “ ‘It is quite possible that
this effect of the [jurisdiction-stripping statute] was not
contemplated by Congress. . . . [B]ut when terms are
unambiguous we may not speculate on probabilities of
intention.’ ” 343 U. S., at 116 (quoting 5 Wall., at 544–
545).
   The Court also attempts to evade the Bruner line of
cases by asserting that “the ‘presumption’ [of application
to pending cases] that these cases have applied is more
accurately viewed as the nonapplication of another pre
sumption—viz., the presumption against retroactivity—in
certain limited circumstances.” Ante, at 11. I have al
ready explained that what the Court calls a “presumption”
is simply the acknowledgment of the unambiguous mean
ing of such provisions. But even taking it to be what the
                      Cite as: 548 U. S. ____ (2006)                     5

                          SCALIA, J., dissenting

Court says, the effect upon the present case would be the
same. Prospective applications of a statute are “effective”
upon the statute’s effective date; that is what an effective-
date provision like §1005(h)(1) means.1 “ ‘[S]hall take
effect upon enactment’ is presumed to mean ‘shall have
prospective effect upon enactment,’ and that presumption
is too strong to be overcome by any negative inference
[drawn from other provisions of the statute].” Landgraf,
511 U. S., at 288 (SCALIA, J., concurring in judgments).
The Court’s “nonapplication of . . . the presumption
against retroactivity” to §1005(e)(1) is thus just another
way of stating that the statute takes immediate effect in
pending cases.
  Though the Court resists the Bruner rule, it cannot cite
a single case in the history of Anglo-American law (before
today) in which a jurisdiction-stripping provision was
denied immediate effect in pending cases, absent an ex
plicit statutory reservation. By contrast, the cases grant
ing such immediate effect are legion, and they repeatedly
rely on the plain language of the jurisdictional repeal as
an “inflexible trump,” ante, at 19, by requiring an express
——————
  1 The Court apparently believes that the effective-date provision

means nothing at all. “That paragraph (1), along with paragraphs (2)
and (3), is to ‘take effect on the date of enactment,’ DTA §1005(h)(1),
119 Stat. 2743, is not dispositive,” says the Court, ante, at 14, n. 9. The
Court’s authority for this conclusion is its quote from INS v. St. Cyr,
533 U. S. 289, 317 (2001), to the effect that “a statement that a statute
will become effective on a certain date does not even arguably suggest
that it has any application to conduct that occurred at an earlier date.”
Ante, at 14, n. 9 (emphasis added, internal quotation marks omitted).
But this quote merely restates the obvious: An effective-date provision
does not render a statute applicable to “conduct that occurred at an
earlier date,” but of course it renders the statute applicable to conduct
that occurs on the effective date and all future dates—such as the
Court’s exercise of jurisdiction here. The Court seems to suggest that,
because the effective-date provision does not authorize retroactive
application, it also fails to authorize prospective application (and is
thus useless verbiage). This cannot be true.
6                  HAMDAN v. RUMSFELD

                     SCALIA, J., dissenting

reservation to save pending cases. See, e.g., Bruner, su
pra, at 115; Kline v. Burke Constr. Co., 260 U. S. 226, 234
(1922); Hallowell, 239 U. S., at 508; Gwin v. United States,
184 U. S. 669, 675 (1902); Gurnee v. Patrick County, 137
U. S. 141, 144 (1890); Sherman v. Grinnell, 123 U. S. 679,
680 (1887); Railroad Co. v. Grant, supra, at 403, Assessors
v. Osbornes, 9 Wall. 567, 575 (1870); Ex parte McCardle, 7
Wall., at 514; Ritchie, supra, at 544; Norris v. Crocker, 13
How. 429, 440 (1852); Yeaton v. United States, 5 Cranch
281 (1809) (Marshall, C. J.), discussed in Gwin, supra, at
675; King v. Justices of the Peace of London, 3 Burr. 1456,
1457, 97 Eng. Rep. 924, 925 (K. B. 1764). Cf. National
Exchange Bank of Baltimore v. Peters, 144 U. S. 570, 572
(1892).
                             B
   Disregarding the plain meaning of §1005(e)(1) and the
requirement of explicit exception set forth in the foregoing
cases, the Court instead favors “a negative inference . . .
from the exclusion of language from one statutory provi
sion that is included in other provisions of the same stat
ute,” ante, at 13. Specifically, it appeals to the fact that
§1005(e)(2) and (e)(3) are explicitly made applicable to
pending cases (by §1005(h)(2)). A negative inference of the
sort the Court relies upon might clarify the meaning of an
ambiguous provision, but since the meaning of §1005(e)(1)
is entirely clear, the omitted language in that context
would have been redundant.
   Even if §1005(e)(1) were at all ambiguous in its applica
tion to pending cases, the “negative inference” from
§1005(h)(2) touted by the Court would have no force. The
numerous cases in the Bruner line would at least create a
powerful default “presumption against jurisdiction,” ante,
at 11. The negative inference urged by the Court would be
a particularly awkward and indirect way of rebutting such
a longstanding and consistent practice. This is especially
                 Cite as: 548 U. S. ____ (2006)            7

                     SCALIA, J., dissenting

true since the negative inference that might be drawn
from §1005(h)(2)’s specification that certain provisions
shall apply to pending cases is matched by a negative
inference in the opposite direction that might be drawn
from §1005(b)(2), which provides that certain provisions
shall not apply to pending cases.
  The Court’s reliance on our opinion in Lindh v. Murphy,
521 U. S. 320 (1997), is utterly misplaced. Lindh involved
two provisions of the Antiterrorism and Effective Death
Penalty Act of 1996 (AEDPA): a set of amendments to
chapter 153 of the federal habeas statute that redefined
the scope of collateral review by federal habeas courts; and
a provision creating a new chapter 154 in the habeas
statute specially to govern federal collateral review of
state capital cases. See 521 U. S., at 326–327. The latter
provision explicitly rendered the new chapter 154 applica
ble to cases pending at the time of AEDPA’s enactment;
the former made no specific reference to pending cases.
Id., at 327. In Lindh, we drew a negative inference from
chapter 154’s explicit reference to pending cases, to con
clude that the chapter 153 amendments did not apply in
pending cases. It was essential to our reasoning, however,
that both provisions appeared to be identically difficult to
classify under our retroactivity cases. First, we noted
that, after Landgraf, there was reason for Congress to
suppose that an explicit statement was required to render
the amendments to chapter 154 applicable in pending
cases, because the new chapter 154 “will have substantive
as well as purely procedural effects.” 521 U. S., at 327.
The next step—and the critical step—in our reasoning was
that Congress had identical reason to suppose that an
explicit statement would be required to apply the chapter
153 amendments to pending cases, but did not provide it.
Id., at 329. The negative inference of Lindh rested on the
fact that “[n]othing . . . but a different intent explain[ed]
the different treatment.” Ibid.
8                     HAMDAN v. RUMSFELD

                         SCALIA, J., dissenting

   Here, by contrast, there is ample reason for the different
treatment. The exclusive-review provisions of the DTA,
unlike both §1005(e)(1) and the AEDPA amendments in
Lindh, confer new jurisdiction (in the D. C. Circuit) where
there was none before. For better or for worse, our recent
cases have contrasted jurisdiction-creating provisions with
jurisdiction-ousting provisions, retaining the venerable
rule that the latter are not retroactive even when applied
in pending cases, but strongly indicating that the former
are typically retroactive. For example, we stated in
Hughes Aircraft Co. v. United States ex rel. Schumer, 520
U. S. 939, 951 (1997), that a statute “that creates jurisdic
tion where none previously existed” is “as much subject to
our presumption against retroactivity as any other.” See
also Republic of Austria v. Altmann, 541 U. S. 677, 695
(2004) (opinion for the Court by STEVENS, J.); id., at 722
(KENNEDY, J., dissenting). The Court gives our retroactiv
ity jurisprudence a dazzling clarity in asserting that “sub
sections (e)(2) and (e)(3) ‘confer’ jurisdiction in a manner
that cannot conceivably give rise to retroactivity questions
under our precedents.”2 Ante, at 17–18. This statement
——————
  2 A comparison with Lindh v. Murphy, 521 U. S. 320 (1997), shows

this not to be true. Subsections (e)(2) and (e)(3) of §1005 resemble
the provisions of AEDPA at issue in Lindh (whose retroactivity
as applied to pending cases the Lindh majority did not rule upon,
see 521 U. S., at 326), in that they “g[o] beyond ‘mere’ procedure,”
id., at 327. They impose novel and unprecedented disabilities on
the Executive Branch in its conduct of military affairs. Subsection
(e)(2) imposes judicial review on the Combatant Status Review
Tribunals (CSRTs), whose implementing order did not subject them
to review by Article III courts. See Memorandum from Deputy
Secretary of Defense Paul Wolfowitz re: Order Establishing Com
batant Status Review Tribunals, at 3 §h (July 7, 2004), avail
able at http://www.defenselink.mil/news/Jul2004/d20040707review.pdf
(all Internet materials as visited June 27, 2006, and available
in Clerk of Court’s case file). Subsection (e)(3) authorizes the D. C.
Circuit to review “the validity of any final decision rendered pursuant
to Military Commission Order No. 1,” §1005(e)(3)(A), 119 Stat. 2743.
                     Cite as: 548 U. S. ____ (2006)                     9

                          SCALIA, J., dissenting

rises to the level of sarcasm when one considers its au
thor’s description of the governing test of our retroactivity
jurisprudence:
     “The conclusion that a particular rule operates ‘retro
     actively’ comes at the end of a process of judgment
     concerning the nature and extent of the change in the
     law and the degree of connection between the opera
     tion of the new rule and a relevant past event. Any
     test of retroactivity will leave room for disagreement
     in hard cases, and is unlikely to classify the enormous
     variety of legal changes with perfect philosophical
     clarity. However, retroactivity is a matter on which
     judges tend to have ‘sound . . . instinct[s],’ . . . and fa
     miliar considerations of fair notice, reasonable reli
     ance, and settled expectations offer sound guidance.”
     Landgraf, 511 U. S., at 270 (opinion for the Court by
     STEVENS, J.).
The only “familiar consideration,” “reasonable reliance,”
and “settled expectation” I am aware of pertaining to the
present case is the rule of Bruner—applicable to
§1005(e)(1), but not to §1005(e)(2) and (3)—which the
——————
Historically, federal courts have never reviewed the validity of the final
decision of any military commission; their jurisdiction has been re
stricted to considering the commission’s “lawful authority to hear,
decide and condemn,” In re Yamashita, 327 U. S. 1, 8 (1946) (emphasis
added). See also Johnson v. Eisentrager, 339 U. S. 763, 786–787 (1950).
Thus, contrary to the Court’s suggestion, ante, at 17, subsections (e)(2)
and (e)(3) confer new jurisdiction: They impose judicial oversight on a
traditionally unreviewable exercise of military authority by the Com
mander in Chief. They arguably “spea[k] not just to the power of a
particular court but to . . . substantive rights . . . as well,” Hughes
Aircraft Co. v. United States ex rel. Shumer, 520 U. S. 939, 951 (1997)—
namely, the unreviewable powers of the President. Our recent cases
had reiterated that the Executive is protected by the presumption
against retroactivity in such comparatively trivial contexts as suits for
tax refunds and increased pay, see Landgraf v. USI Film Products, 511
U. S. 244, 271, n. 25 (1994).
10                  HAMDAN v. RUMSFELD

                      SCALIA, J., dissenting

Court stubbornly disregards. It is utterly beyond question
that §1005(e)(2)’s and (3)’s application to pending cases
(without explicit specification) was not as clear as
§1005(e)(1)’s. That is alone enough to explain the differ
ence in treatment.
   Another obvious reason for the specification was to stave
off any Suspension Clause problems raised by the imme
diately effective ouster of jurisdiction brought about by
subsection (e)(1). That is to say, specification of the im
mediate effectiveness of subsections (e)(2) and (e)(3)
(which, unlike subsection (e)(1), would not fall within the
Bruner rule and would not automatically be deemed appli
cable in pending cases) could reasonably have been
thought essential to be sure of replacing the habeas juris
diction that subsection (e)(1) eliminated in pending cases
with an adequate substitute. See infra, at 16–18.
   These considerations by no means prove that an explicit
statement would be required to render subsections (e)(2)
and (e)(3) applicable in pending cases. But they surely
gave Congress ample reason to doubt that their applica
tion in pending cases would unfold as naturally as the
Court glibly assumes. In any event, even if it were true
that subsections (e)(2) and (e)(3) “ ‘confer’ jurisdiction in a
manner that cannot conceivably give rise to retroactivity
questions,” ante, at 17–18, this would merely establish
that subsection (h)(2)’s reference to pending cases was
wholly superfluous when applied to subsections (e)(2) and
(e)(3), just as it would have been for subsection (e)(1).
Lindh’s negative inference makes sense only when Con
gress would have perceived “the wisdom of being explicit”
with respect to the immediate application of both of two
statutory provisions, 521 U. S., at 328, but chose to be
explicit only for one of them—not when it would have
perceived no need to be explicit for both, but enacted a
redundancy only for one.
                 Cite as: 548 U. S. ____ (2006)           11

                     SCALIA, J., dissenting

   In short, it is simply untrue that Congress “ ‘should have
been just as concerned about’ ” specifying the application
of §1005(e)(1) to pending cases, ante, at 14 (quoting Lindh,
521 U. S., at 329). In fact, the negative-inference ap
proach of Lindh is particularly inappropriate in this case,
because the negative inference from §1005(h)(2) would
tend to defeat the purpose of the very provisions that are
explicitly rendered applicable in pending cases, §1005(e)(2)
and (3). Those provisions purport to vest “exclusive”
jurisdiction in the D. C. Circuit to consider the claims
raised by petitioners here. See infra, at 16–18. By draw
ing a negative inference à la Lindh, the Court supplants
this exclusive-review mechanism with a dual-review
mechanism for petitioners who were expeditious enough to
file applications challenging the CSRTs or military com
missions before December 30, 2005. Whatever the force of
Lindh’s negative inference in other cases, it surely should
not apply here to defeat the purpose of the very provision
from which the negative inference is drawn.
                             C
   Worst of all is the Court’s reliance on the legislative
history of the DTA to buttress its implausible reading of
§1005(e)(1). We have repeatedly held that such reliance is
impermissible where, as here, the statutory language is
unambiguous. But the Court nevertheless relies both on
floor statements from the Senate and (quite heavily) on
the drafting history of the DTA. To begin with floor
statements: The Court urges that some “statements made
by Senators preceding passage of the Act lend further
support to” the Court’s interpretation, citing excerpts from
the floor debate that support its view, ante, 15–16, n. 10.
The Court immediately goes on to discount numerous floor
statements by the DTA’s sponsors that flatly contradict its
view, because “those statements appear to have been
inserted into the Congressional Record after the Senate
12                     HAMDAN v. RUMSFELD

                         SCALIA, J., dissenting

debate.” Ibid. Of course this observation, even if true,
makes no difference unless one indulges the fantasy that
Senate floor speeches are attended (like the Philippics of
Demosthenes) by throngs of eager listeners, instead of
being delivered (like Demosthenes’ practice sessions on
the beach) alone into a vast emptiness. Whether the floor
statements are spoken where no Senator hears, or written
where no Senator reads, they represent at most the views
of a single Senator. In any event, the Court greatly exag
gerates the one-sidedness of the portions of the floor de
bate that clearly occurred before the DTA’s enactment.
Some of the statements of Senator Graham, a sponsor of
the bill, only make sense on the assumption that pending
cases are covered.3 And at least one opponent of the DTA
unmistakably expressed his understanding that it would
terminate our jurisdiction in this very case.4 (Of course in
its discussion of legislative history the Court wholly ig
nores the President’s signing statement, which explicitly
set forth his understanding that the DTA ousted jurisdic
——————
  3 “Because I have described how outrageous these claims are—about

the exercise regime, the reading materials—most Americans would be
highly offended to know that terrorists are suing us in our own courts
about what they read.” 151 Cong. Rec. S12756 (Nov. 14, 2005). “In
stead of having unlimited habeas corpus opportunities under the
Constitution, we give every enemy combatant, all 500, a chance to go to
Federal court, the Circuit Court of Appeals for the District of Colum
bia. . . . It will be a one-time deal.” Id., at S12754. “This Levin-
Graham-Kyl amendment allows every detainee under our control to
have their day in court. They are allowed to appeal their convictions.”
Id., at S12801 (Nov. 15, 2005); see also id., at S12799 (rejecting the
notion that “an enemy combatant terrorist al-Qaida member should be
able to have access to our Federal courts under habeas like an Ameri
can citizen”).
  4 “An earlier part of the amendment provides that no court, justice, or

judge shall have jurisdiction to consider the application for writ of
habeas corpus. . . . Under the language of exclusive jurisdiction in the
DC Circuit, the U. S. Supreme Court would not have jurisdiction to
hear the Hamdan case . . . .” Id., at S12796 (statement of Sen. Specter).
                     Cite as: 548 U. S. ____ (2006)                  13

                         SCALIA, J., dissenting

tion over pending cases.5)
   But selectivity is not the greatest vice in the Court’s use
of floor statements to resolve today’s case. These state
ments were made when Members of Congress were fully
aware that our continuing jurisdiction over this very case
was at issue. The question was divisive, and floor state
ments made on both sides were undoubtedly opportunistic
and crafted solely for use in the briefs in this very litiga
tion. See, e.g., 151 Cong. Rec. S14257–S14258 (Dec. 21,
2005) (statement of Sen. Levin) (arguing against a reading
that would “stri[p] the Federal courts of jurisdiction to
consider pending cases, including the Hamdan case now
pending in the Supreme Court,” and urging that Lindh
requires the same negative inference that the Court in
dulges today (emphasis added)). The Court’s reliance on
such statements cannot avoid the appearance of similar
opportunism. In a virtually identical context, the author
of today’s opinion has written for the Court that “[t]he
legislative history discloses some frankly partisan state
ments about the meaning of the final effective date lan
guage, but those statements cannot plausibly be read as
reflecting any general agreement.” Landgraf, 511 U. S., at
262 (opinion for the Court by STEVENS, J.). Likewise, the
handful of floor statements that the Court treats as au
thoritative do not “reflec[t] any general agreement.” They
reflect the now-common tactic—which the Court once
again rewards—of pursuing through floor-speech ipse dixit

——————
   5 “[T]he executive branch shall construe section 1005 to preclude the

Federal courts from exercising subject matter jurisdiction over any
existing or future action, including applications for writs of habeas
corpus, described in section 1005.” President’s Statement on Signing
of H. R. 2863, the “Department of Defense, Emergency Supple
mental Appropriations to Address Hurricanes in the Gulf of
Mexico, and Pandemic Influenza Act, 2006” (Dec. 30, 2005), available
at      http://www.whitehouse.gov/news/releases/2005/12/print/20051230
8.html.
14                     HAMDAN v. RUMSFELD

                          SCALIA, J., dissenting

what could not be achieved through the constitutionally
prescribed method of putting language into a bill that a
majority of both Houses vote for and the President signs.
    With regard to the floor statements, at least the Court
shows some semblance of seemly shame, tucking away its
reference to them in a half-hearted footnote. Not so for its
reliance on the DTA’s drafting history, which is displayed
prominently, see ante, at 14–15. I have explained else
where that such drafting history is no more legitimate or
reliable an indicator of the objective meaning of a statute
than any other form of legislative history. This case pre
sents a textbook example of its unreliability. The Court,
ante, at 14, trumpets the fact that a bill considered in the
Senate included redundant language, not included in the
DTA as passed, reconfirming that the abolition of habeas
jurisdiction “shall apply to any application or other action
that is pending on or after the date of the enactment of
this Act.” 151 Cong. Rec. S12655 (Nov. 10, 2005). But this
earlier version of the bill also differed from the DTA in
other material respects. Most notably, it provided for
postdecision review by the D. C. Circuit only of the deci
sions of CSRTs, not military commissions, ibid.; and it
limited that review to whether “the status determination
. . . was consistent with the procedures and standards
specified by the Secretary of Defense,” ibid., not whether
“the use of such standards and procedures . . . is consistent
with the Constitution and laws of the United States,” DTA
§1005(e)(2)(C)(ii), 119 Stat. 2742. To say that what moved
Senators to reject this earlier bill was the “action that is
pending” provision surpasses the intuitive powers of even
this Court’s greatest Justices.6 And to think that the
House and the President also had this rejection firmly in
——————
   6 The Court asserts that “it cannot be said that the changes to subsec

tion (h)(2) were inconsequential,” ante, at 15, n. 10, but the Court’s sole
evidence is the self-serving floor statements that it selectively cites.
                 Cite as: 548 U. S. ____ (2006)           15

                     SCALIA, J., dissenting

mind is absurd. As always—but especially in the context
of strident, partisan legislative conflict of the sort that
characterized enactment of this legislation—the language
of the statute that was actually passed by both Houses of
Congress and signed by the President is our only authori
tative and only reliable guidepost.
                              D
   A final but powerful indication of the fact that the Court
has made a mess of this statute is the nature of the conse
quences that ensue. Though this case concerns a habeas
application challenging a trial by military commission,
DTA §1005(e)(1) strips the courts of jurisdiction to hear or
consider any “application for a writ of habeas corpus filed
by or on behalf of an alien detained by the Department of
Defense at Guantanamo Bay, Cuba.” The vast majority of
pending petitions, no doubt, do not relate to military
commissions at all, but to more commonly challenged
aspects of “detention” such as the terms and conditions of
confinement. See Rasul v. Bush, 542 U. S. 466, 498 (2004)
(SCALIA, J., dissenting). The Solicitor General represents
that “[h]abeas petitions have been filed on behalf of a
purported 600 [Guantanamo Bay] detainees,” including
one that “seek[s] relief on behalf of every Guantanamo
detainee who has not already filed an action,” Respon
dents’ Motion to Dismiss for Lack of Jurisdiction 20, n. 10
(hereinafter Motion to Dismiss). The Court’s interpreta
tion transforms a provision abolishing jurisdiction over all
Guantanamo-related habeas petitions into a provision that
retains jurisdiction over cases sufficiently numerous to
keep the courts busy for years to come.
                            II
  Because I would hold that §1005(e)(1) unambiguously
terminates the jurisdiction of all courts to “hear or con
sider” pending habeas applications, I must confront peti
16                 HAMDAN v. RUMSFELD

                     SCALIA, J., dissenting

tioner’s arguments that the provision, so interpreted,
violates the Suspension Clause. This claim is easily dis
patched. We stated in Johnson v. Eisentrager, 339 U. S.
763, 768 (1950):
     “We are cited to no instance where a court, in this or
     any other country where the writ is known, has issued
     it on behalf of an alien enemy who, at no relevant
     time and in no stage of his captivity, has been within
     its territorial jurisdiction. Nothing in the text of the
     Constitution extends such a right, nor does anything
     in our statutes.”
Notwithstanding the ill-considered dicta in the Court’s
opinion in Rasul, 542 U. S., at 480–481, it is clear that
Guantanamo Bay, Cuba, is outside the sovereign “territo
rial jurisdiction” of the United States. See id., at 500–505
(SCALIA, J., dissenting). Petitioner, an enemy alien de
tained abroad, has no rights under the Suspension Clause.
  But even if petitioner were fully protected by the
Clause, the DTA would create no suspension problem.
This Court has repeatedly acknowledged that “the substi
tution of a collateral remedy which is neither inadequate
nor ineffective to test the legality of a person’s detention
does not constitute a suspension of the writ of habeas
corpus.” Swain v. Pressley, 430 U. S. 372, 381 (1977); see
also INS v. St. Cyr, 533 U. S. 289, 314, n. 38 (2006) (“Con
gress could, without raising any constitutional questions,
provide an adequate substitute through the courts of
appeals”).
  Petitioner has made no showing that the postdecision
exclusive review by the D. C. Circuit provided in
§1005(e)(3) is inadequate to test the legality of his trial by
military commission. His principal argument is that the
exclusive-review provisions are inadequate because they
foreclose review of the claims he raises here. Though
petitioner’s brief does not parse the statutory language,
                 Cite as: 548 U. S. ____ (2006)          17

                     SCALIA, J., dissenting

his argument evidently rests on an erroneously narrow
reading of DTA §1005(e)(3)(D)(ii), 119 Stat. 2743. That
provision grants the D. C. Circuit authority to review, “to
the extent the Constitution and laws of the United States
are applicable, whether the use of such standards and
procedures to reach the final decision is consistent with
the Constitution and laws of the United States.” In the
quoted text, the phrase “such standards and procedures”
refers to “the standards and procedures specified in the
military order referred to in subparagraph (A),” namely
“Military Commission Order No. 1, dated August 31, 2005
(or any successor military order).” DTA §1005(e)(3)(D)(i),
(e)(3)(A), ibid. This Military Commission Order (Order
No. 1) is the Department of Defense’s fundamental imple
menting order for the President’s order authorizing trials
by military commission. Order No. 1 establishes commis
sions, §2; delineates their jurisdiction, §3; provides for
their officers, §4(A); provides for their prosecution and
defense counsel, §4(B), (C); lays out all their procedures,
both pretrial and trial, §5(A)–(P), §6(A)–(G); and provides
for posttrial military review through the Secretary of
Defense and the President, §6(H). In short, the “standards
and procedures specified in” Order No. 1 include every
aspect of the military commissions, including the fact of
their existence and every respect in which they differ from
courts-martial. Petitioner’s claims that the President
lacks legal authority to try him before a military commis
sion constitute claims that “the use of such standards and
procedures,” as specified in Order No. 1, is “[in]consistent
with the Constitution and laws of the United States,” DTA
§1005(e)(3)(D)(ii), 119 Stat. 2743. The D. C. Circuit thus
retains jurisdiction to consider these claims on postdeci
sion review, and the Government does not dispute that the
DTA leaves unaffected our certiorari jurisdiction under 28
U. S. C. §1254(1) to review the D. C. Circuit’s decisions.
Motion to Dismiss 16, n. 8. Thus, the DTA merely defers
18                     HAMDAN v. RUMSFELD

                          SCALIA, J., dissenting

our jurisdiction to consider petitioner’s claims; it does not
eliminate that jurisdiction. It constitutes neither an
“inadequate” nor an “ineffective” substitute for petitioner’s
pending habeas application.7
   Though it does not squarely address the issue, the Court
hints ominously that “the Government’s preferred read
ing” would “rais[e] grave questions about Congress’ au
thority to impinge upon this Court’s appellate jurisdiction,
particularly in habeas cases.” Ante, at 10–11 (citing Ex
parte Yerger, 8 Wall. 85 (1869); Felker v. Turpin, 518 U. S.
651 (1996); Durousseau v. United States, 6 Cranch 307
(1810); United States v. Klein, 13 Wall. 128 (1872); and Ex
parte McCardle, 7 Wall. 506). It is not clear how there
could be any such lurking questions, in light of the aptly
named “Exceptions Clause” of Article III, §2, which, in
making our appellate jurisdiction subject to “such Excep
tions, and under such Regulations as the Congress shall
make,” explicitly permits exactly what Congress has done
here. But any doubt our prior cases might have created on
this score is surely chimerical in this case. As just noted,
the exclusive-review provisions provide a substitute for
habeas review adequate to satisfy the Suspension Clause,
——————
   7 Petitioner also urges that he could be subject to indefinite delay if

military officials and the President are deliberately dilatory in review
ing the decision of his commission. In reviewing the constitutionality of
legislation, we generally presume that the Executive will implement its
provisions in good faith. And it is unclear in any event that delay
would inflict any injury on petitioner, who (after an adverse determina
tion by his CSRT, see 344 F. Supp. 2d 152, 161 (DC 2004)) is already
subject to indefinite detention under our decision in Hamdi v. Rums
feld, 542 U. S. 507 (2004). Moreover, the mere possibility of delay does
not render an alternative remedy “inadequate [o]r ineffective to test the
legality” of a military commission trial. Swain v. Pressley, 430 U. S.
372, 381 (1977). In an analogous context, we discounted the notion that
postponement of relief until postconviction review inflicted any cogni
zable injury on a serviceman charged before a military court-martial.
Schlesinger v. Councilman, 420 U. S. 738, 754–755 (1975); see also
Younger v. Harris, 401 U. S. 37, 46 (1971).
                 Cite as: 548 U. S. ____ (2006)           19

                     SCALIA, J., dissenting

which forbids the suspension of the writ of habeas corpus.
A fortiori they provide a substitute adequate to satisfy any
implied substantive limitations, whether real or imagi
nary, upon the Exceptions Clause, which authorizes such
exceptions as §1005(e)(1).
                              III
   Even if Congress had not clearly and constitutionally
eliminated jurisdiction over this case, neither this Court
nor the lower courts ought to exercise it. Traditionally,
equitable principles govern both the exercise of habeas
jurisdiction and the granting of the injunctive relief sought
by petitioner. See Schlesinger v. Councilman, 420 U. S.
738, 754 (1975); Weinberger v. Romero-Barcelo, 456 U. S.
305, 311 (1982). In light of Congress’s provision of an
alternate avenue for petitioner’s claims in §1005(e)(3),
those equitable principles counsel that we abstain from
exercising jurisdiction in this case.
   In requesting abstention, the Government relies princi
pally on Councilman, in which we abstained from consid
ering a serviceman’s claim that his charge for marijuana
possession was not sufficiently “service-connected” to
trigger the subject-matter jurisdiction of the military
courts-martial. See 420 U. S., at 740, 758. Admittedly,
Councilman does not squarely control petitioner’s case,
but it provides the closest analogue in our jurisprudence.
As the Court describes, ante, at 21, Councilman “identi
fie[d] two considerations of comity that together favor[ed]
abstention pending completion of ongoing court-martial
proceedings against service personnel.” But the Court
errs in finding these considerations inapplicable to this
case. Both of them, and a third consideration not empha
sized in Councilman, all cut in favor of abstention here.
   First, the Court observes that Councilman rested in
part on the fact that “military discipline and, therefore,
the efficient operation of the Armed Forces are best served
20                 HAMDAN v. RUMSFELD

                     SCALIA, J., dissenting

if the military justice system acts without regular inter
ference from civilian courts,” and concludes that “Hamdan
is not a member of our Nation’s Armed Forces, so concerns
about military discipline do not apply.” Ante, at 22. This
is true enough. But for some reason, the Court fails to
make any inquiry into whether military commission trials
might involve other “military necessities” or “unique mili
tary exigencies,” 420 U. S., at 757, comparable in gravity
to those at stake in Councilman. To put this in context:
The charge against the respondent in Councilman was the
off-base possession and sale of marijuana while he was
stationed in Fort Sill, Oklahoma, see id., at 739–740. The
charge against the petitioner here is joining and actively
abetting the murderous conspiracy that slaughtered thou
sands of innocent American civilians without warning on
September 11, 2001. While Councilman held that the
prosecution of the former charge involved “military neces
sities” counseling against our interference, the Court does
not even ponder the same question for the latter charge.
   The reason for the Court’s “blinkered study” of this
question, ante, at 19, is not hard to fathom. The principal
opinion on the merits makes clear that it does not believe
that the trials by military commission involve any “mili
tary necessity” at all: “The charge’s shortcomings . . . are
indicative of a broader inability on the Executive’s part
here to satisfy the most basic precondition . . . for estab
lishment of military commissions: military necessity.”
Ante, at 48. This is quite at odds with the views on this
subject expressed by our political branches. Because of
“military necessity,” a joint session of Congress authorized
the President to “use all necessary and appropriate force,”
including military commissions, “against those nations,
organizations, or persons [such as petitioner] he deter
mines planned, authorized, committed, or aided the terror
ist attacks that occurred on September 11, 2001.” Au
thorization for Use of Military Force, §2(a), 115 Stat. 224,
                  Cite as: 548 U. S. ____ (2006)            21

                      SCALIA, J., dissenting

note following 50 U. S. C. §1541 (2000 ed., Supp. III). In
keeping with this authority, the President has determined
that “[t]o protect the United States and its citizens, and
for the effective conduct of military operations and preven
tion of terrorist attacks, it is necessary for individuals
subject to this order . . . to be detained, and, when tried, to
be tried for violations of the laws of war and other appli
cable laws by military tribunals.” Military Order of Nov.
13, 2001, 3 CFR §918(e) (2002). It is not clear where the
Court derives the authority—or the audacity—to contra
dict this determination. If “military necessities” relating
to “duty” and “discipline” required abstention in Council
man, supra, at 757, military necessities relating to the
disabling, deterrence, and punishment of the mass-
murdering terrorists of September 11 require abstention
all the more here.
   The Court further seeks to distinguish Councilman on
the ground that “the tribunal convened to try Hamdan is
not part of the integrated system of military courts, com
plete with independent review panels, that Congress has
established.” Ante, at 22. To be sure, Councilman empha
sized that “Congress created an integrated system of
military courts and review procedures, a critical element
of which is the Court of Military Appeals consisting of
civilian judges completely removed from all military influ
ence or persuasion, who would gain over time thorough
familiarity with military problems.” 420 U. S., at 758
(internal quotation marks and footnote omitted). The
Court contrasts this “integrated system” insulated from
military influence with the review scheme established by
Order No. 1, which “provides that appeal of a review
panel’s decision may be had only to the Secretary of De
fense himself, §6(H)(5), and then, finally, to the President,
§6(H)(6).” Ante, at 23.
   Even if we were to accept the Court’s extraordinary
assumption that the President “lack[s] the structural
22                     HAMDAN v. RUMSFELD

                          SCALIA, J., dissenting

insulation from military influence that characterizes the
Court of Appeals for the Armed Forces,” ante, at 23,8 the
Court’s description of the review scheme here is anachro
nistic. As of December 30, 2005, the “fina[l]” review of
decisions by military commissions is now conducted by the
D. C. Circuit pursuant to §1005(e)(3) of the DTA, and by
this Court under 28 U. S. C. §1254(1). This provision for
review by Article III courts creates, if anything, a review
scheme more insulated from Executive control than that in
Councilman.9 At the time we decided Councilman, Con
gress had not “conferred on any Art[icle] III court jurisdic
tion directly to review court-martial determinations.” 420
U. S., at 746. The final arbiter of direct appeals was the
Court of Military Appeals (now the Court of Appeals for
——————
  8 The  very purpose of Article II’s creation of a civilian Commander in
Chief in the President of the United States was to generate “structural
insulation from military influence.” See The Federalist No. 28 (A. Hamil
ton); id., No. 69 (same). We do not live under a military junta. It is a
disservice to both those in the Armed Forces and the President to suggest
that the President is subject to the undue control of the military.
   9 In rejecting our analysis, the Court observes that appeals to the

D. C. Circuit under subsection (e)(3) are discretionary, rather than as of
right, when the military commission imposes a sentence less than 10
years’ imprisonment, see ante, at 23, n. 19, 52–53; §1005(e)(3)(B), 119
Stat. 2743. The relevance of this observation to the abstention question
is unfathomable. The fact that Article III review is discretionary does
not mean that it lacks “structural insulation from military influence,”
ante, at 23, and its discretionary nature presents no obstacle to the
courts’ future review these cases.
   The Court might more cogently have relied on the discretionary na
ture of review to argue that the statute provides an inadequate substi
tute for habeas review under the Suspension Clause. See supra, at 16–
18. But this argument would have no force, even if all appeals to the
D. C. Circuit were discretionary. The exercise of habeas jurisdiction
has traditionally been entirely a matter of the court’s equitable discre
tion, see Withrow v. Williams, 507 U. S. 680, 715–718 (1993) (SCALIA,
J., concurring in part and dissenting in part), so the fact that habeas
jurisdiction is replaced by discretionary appellate review does not
render the substitution “inadequate.” Swain, 430 U. S., at 381.
                 Cite as: 548 U. S. ____ (2006)           23

                     SCALIA, J., dissenting

the Armed Forces), an Article I court whose members
possessed neither life tenure, nor salary protection, nor
the constitutional protection from removal provided to
federal judges in Article III, §1. See 10 U. S. C. §867(a)(2)
(1970 ed.).
  Moreover, a third consideration counsels strongly in
favor of abstention in this case. Councilman reasoned
that the “considerations of comity, the necessity of respect
for coordinate judicial systems” that motivated our deci
sion in Younger v. Harris, 401 U. S. 37 (1971), were inap
plicable to courts-martial, because “the particular de
mands of federalism are not implicated.” 420 U. S., at
756, 757. Though military commissions likewise do not
implicate “the particular demands of federalism,” consid
erations of interbranch comity at the federal level weigh
heavily against our exercise of equity jurisdiction in this
case. Here, apparently for the first time in history, see
Motion to Dismiss 6, a District Court enjoined ongoing
military commission proceedings, which had been deemed
“necessary” by the President “[t]o protect the United
States and its citizens, and for the effective conduct of
military operations and prevention of terrorist attacks.”
Military Order of Nov. 13, 3 CFR §918(e). Such an order
brings the Judicial Branch into direct conflict with the
Executive in an area where the Executive’s competence is
maximal and ours is virtually nonexistent. We should
exercise our equitable discretion to avoid such conflict.
Instead, the Court rushes headlong to meet it. Elsewhere,
we have deferred exercising habeas jurisdiction until state
courts have “the first opportunity to review” a petitioner’s
claim, merely to “reduc[e] friction between the state and
federal court systems.” O’Sullivan v. Boerckel, 526 U. S.
838, 844, 845 (1999). The “friction” created today between
this Court and the Executive Branch is many times more
serious.
  In the face of such concerns, the Court relies heavily on
24                  HAMDAN v. RUMSFELD

                      SCALIA, J., dissenting

Ex parte Quirin, 317 U. S. 1 (1942): “Far from abstaining
pending the conclusion of military proceedings, which
were ongoing, [in Quirin] we convened a special Term to
hear the case and expedited our review.” Ante, at 24. It is
likely that the Government in Quirin, unlike here, pre
ferred a hasty resolution of the case in this Court, so that
it could swiftly execute the sentences imposed, see Hamdi
v. Rumsfeld, 542 U. S. 507, 569 (2004) (SCALIA, J., dissent
ing). But the Court’s reliance on Quirin suffers from a
more fundamental defect: Once again, it ignores the DTA,
which creates an avenue for the consideration of peti
tioner’s claims that did not exist at the time of Quirin.
Collateral application for habeas review was the only
vehicle available. And there was no compelling reason to
postpone consideration of the Quirin application until the
termination of military proceedings, because the only
cognizable claims presented were general challenges to the
authority of the commissions that would not be affected by
the specific proceedings. See supra, at 8–9, n. 2. In the
DTA, by contrast, Congress has expanded the scope of
Article III review and has channeled it exclusively through
a single, postverdict appeal to Article III courts. Because
Congress has created a novel unitary scheme of Article III
review of military commissions that was absent in 1942,
Quirin is no longer governing precedent.
   I would abstain from exercising our equity jurisdiction,
as the Government requests.
                        *    *      * 

     For the foregoing reasons, I dissent. 

                 Cite as: 548 U. S. ____ (2006)            1

                    THOMAS, J., dissenting

SUPREME COURT OF THE UNITED STATES
                         _________________

                          No. 05–184
                         _________________


 SALIM AHMED HAMDAN, PETITIONER v. DONALD
  H. RUMSFELD, SECRETARY OF DEFENSE, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

    APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT

                        [June 29, 2006] 


  JUSTICE THOMAS, with whom JUSTICE SCALIA joins, and
with whom JUSTICE ALITO joins in all but Parts I, II–C–1,
and III–B–2, dissenting.
  For the reasons set forth in JUSTICE SCALIA’s dissent, it
is clear that this Court lacks jurisdiction to entertain
petitioner’s claims, see ante, at 1–11. The Court having
concluded otherwise, it is appropriate to respond to the
Court’s resolution of the merits of petitioner’s claims
because its opinion openly flouts our well-established duty
to respect the Executive’s judgment in matters of military
operations and foreign affairs. The Court’s evident belief
that it is qualified to pass on the “[m]ilitary necessity,”
ante, at 48, of the Commander in Chief’s decision to em
ploy a particular form of force against our enemies is so
antithetical to our constitutional structure that it simply
cannot go unanswered. I respectfully dissent.
                              I
  Our review of petitioner’s claims arises in the context of
the President’s wartime exercise of his commander-in
chief authority in conjunction with the complete support of
Congress. Accordingly, it is important to take measure of
the respective roles the Constitution assigns to the three
branches of our Government in the conduct of war.
  As I explained in Hamdi v. Rumsfeld, 542 U. S. 507
2                   HAMDAN v. RUMSFELD

                      THOMAS, J., dissenting

(2004), the structural advantages attendant to the Execu
tive Branch—namely, the decisiveness, “ ‘activity, secrecy,
and dispatch’ ” that flow from the Executive’s “ ‘unity,’ ” id.,
at 581 (dissenting opinion) (quoting The Federalist No. 70,
p. 472 (J. Cooke ed. 1961) (A. Hamilton))—led the Foun
ders to conclude that the “President ha[s] primary respon
sibility—along with the necessary power—to protect the
national security and to conduct the Nation’s foreign
relations.” 542 U. S., at 580. Consistent with this conclu
sion, the Constitution vests in the President “[t]he execu
tive Power,” Art. II, §1, provides that he “shall be Com
mander in Chief” of the Armed Forces, §2, and places in
him the power to recognize foreign governments, §3. This
Court has observed that these provisions confer upon the
President broad constitutional authority to protect the
Nation’s security in the manner he deems fit. See, e.g.,
Prize Cases, 2 Black 635, 668 (1863) (“If a war be made by
invasion of a foreign nation, the President is not only
authorized but bound to resist force by force . . . without
waiting for any special legislative authority”); Fleming v.
Page, 9 How. 603, 615 (1850) (acknowledging that the
President has the authority to “employ [the Nation’s
Armed Forces] in the manner he may deem most effectual
to harass and conquer and subdue the enemy”).
   Congress, to be sure, has a substantial and essential
role in both foreign affairs and national security. But
“Congress cannot anticipate and legislate with regard to
every possible action the President may find it necessary
to take or every possible situation in which he might act,”
and “[s]uch failure of Congress . . . does not, ‘especially . . .
in the areas of foreign policy and national security,’ imply
‘congressional disapproval’ of action taken by the Execu
tive.” Dames & Moore v. Regan, 453 U. S. 654, 678 (1981)
(quoting Haig v. Agee, 453 U. S. 280, 291 (1981)). Rather,
in these domains, the fact that Congress has provided the
President with broad authorities does not imply—and the
                 Cite as: 548 U. S. ____ (2006)           3

                    THOMAS, J., dissenting

Judicial Branch should not infer—that Congress intended
to deprive him of particular powers not specifically enu
merated. See Dames & Moore, 453 U. S., at 678 (“[T]he
enactment of legislation closely related to the question of
the President’s authority in a particular case which
evinces legislative intent to accord the President broad
discretion may be considered to invite measures on inde
pendent presidential responsibility” (internal quotation
marks omitted)).
    When “the President acts pursuant to an express or
implied authorization from Congress,” his actions are
“ ‘supported by the strongest of presumptions and the
widest latitude of judicial interpretation, and the burden
of persuasion . . . rest[s] heavily upon any who might
attack it.’ ” Id., at 668 (quoting Youngstown Sheet & Tube
Co. v. Sawyer, 343 U. S. 579, 637 (1952) (Jackson, J.,
concurring)). Accordingly, in the very context that we
address today, this Court has concluded that “the deten
tion and trial of petitioners—ordered by the President in
the declared exercise of his powers as Commander in Chief
of the Army in time of war and of grave public danger—
are not to be set aside by the courts without the clear
conviction that they are in conflict with the Constitution
or laws of Congress constitutionally enacted.” Ex parte
Quirin, 317 U. S. 1, 25 (1942).
    Under this framework, the President’s decision to try
Hamdan before a military commission for his involvement
with al Qaeda is entitled to a heavy measure of deference.
In the present conflict, Congress has authorized the Presi
dent “to use all necessary and appropriate force against
those nations, organizations, or persons he determines
planned, authorized, committed, or aided the terrorist
attacks that occurred on September 11, 2001 . . . in order
to prevent any future acts of international terrorism
against the United States by such nations, organizations
or persons.” Authorization for Use of Military Force
4                  HAMDAN v. RUMSFELD

                    THOMAS, J., dissenting

(AUMF) 115 Stat. 224, note following 50 U. S. C. §1541
(2000 ed., Supp. III) (emphasis added). As a plurality of
the Court observed in Hamdi, the “capture, detention, and
trial of unlawful combatants, by ‘universal agreement and
practice,’ are ‘important incident[s] of war,’ ” Hamdi, 542
U. S., at 518 (quoting Quirin, supra, at 28, 30; emphasis
added), and are therefore “an exercise of the ‘necessary
and appropriate force’ Congress has authorized the Presi
dent to use.” Hamdi, 542 U. S., at 518; id., at 587 (THO
MAS, J., dissenting). Hamdi’s observation that military
commissions are included within the AUMF’s authoriza
tion is supported by this Court’s previous recognition that
“[a]n important incident to the conduct of war is the adop
tion of measures by the military commander, not only to
repel and defeat the enemy, but to seize and subject to
disciplinary measures those enemies who, in their attempt
to thwart or impede our military effort, have violated the
law of war.” In re Yamashita, 327 U. S. 1, 11 (1946); see
also Quirin, supra, at 28–29; Madsen v. Kinsella, 343 U. S.
341, 354, n. 20 (1952) (“ ‘[T]he military commission . . . is
an institution of the greatest importance in the period of
war and should be preserved’ ” (quoting S. Rep. No. 229,
63d Cong., 2d Sess., 53 (1914) (testimony of Gen. Crowder))).
   Although the Court concedes the legitimacy of the Presi
dent’s use of military commissions in certain circum
stances, ante, at 28, it suggests that the AUMF has no
bearing on the scope of the President’s power to utilize
military commissions in the present conflict, ante, at 29–
30. Instead, the Court determines the scope of this power
based exclusively on Article 21 of the Uniform Code of
Military Justice (UCMJ), 10 U. S. C. §821, the successor to
Article 15 of the Articles of War, which Quirin held “au
thorized trial of offenses against the law of war before
[military] commissions.” 317 U. S., at 29. As I shall dis
cuss below, Article 21 alone supports the use of commis
sions here. Nothing in the language of Article 21, how
                     Cite as: 548 U. S. ____ (2006)                     5

                         THOMAS, J., dissenting

ever, suggests that it outlines the entire reach of congres
sional authorization of military commissions in all con
flicts—quite the contrary, the language of Article 21 pre
supposes the existence of military commissions under an
independent basis of authorization.1 Indeed, consistent
with Hamdi’s conclusion that the AUMF itself authorizes
the trial of unlawful combatants, the original sanction for
military commissions historically derived from congres
sional authorization of “the initiation of war” with its
attendant authorization of “the employment of all neces
sary and proper agencies for its due prosecution.” W.
Winthrop, Military Law and Precedents 831 (2d ed. 1920)
(hereinafter Winthrop). Accordingly, congressional au
thorization for military commissions pertaining to the
instant conflict derives not only from Article 21 of the
UCMJ, but also from the more recent, and broader, au
thorization contained in the AUMF.2
   I note the Court’s error respecting the AUMF not be
cause it is necessary to my resolution of this case—
Hamdan’s military commission can plainly be sustained
solely under Article 21—but to emphasize the complete
congressional sanction of the President’s exercise of his
commander-in-chief authority to conduct the present war.
In such circumstances, as previously noted, our duty to
——————
   1 As previously noted, Article 15 of the Articles of War was the prede

cessor of Article 21 of the UCMJ. Article 21 provides as follows: “The
provisions of this chapter conferring jurisdiction upon courts-martial do
not deprive military commissions, provost courts, or other military
tribunals of concurrent jurisdiction with respect to offenders or offenses
that by statute or by the law of war may be tried by military commis
sions, provost courts, or other military tribunals.” 10 U. S. C. §821.
   2 Although the President very well may have inherent authority to try

unlawful combatants for violations of the law of war before military
commissions, we need not decide that question because Congress has
authorized the President to do so. Cf. Hamdi v. Rumsfeld, 542 U. S.
507, 587 (2004) (THOMAS, J., dissenting) (same conclusion respecting
detention of unlawful combatants).
6                   HAMDAN v. RUMSFELD

                     THOMAS, J., dissenting

defer to the Executive’s military and foreign policy judg
ment is at its zenith; it does not countenance the kind of
second-guessing the Court repeatedly engages in today.
Military and foreign policy judgments
    “ ‘are and should be undertaken only by those directly
    responsible to the people whose welfare they advance
    or imperil. They are decisions of a kind for which the
    Judiciary has neither aptitude, facilities nor responsi
    bility and which has long been held to belong in the
    domain of political power not subject to judicial intru
    sion or inquiry.’ ” Hamdi, supra, at 582–583 (THOMAS,
    J., dissenting) (quoting Chicago & Southern Air Lines,
    Inc. v. Waterman S. S. Corp., 333 U. S. 103, 111 (1948)).
It is within this framework that the lawfulness of Ham
dan’s commission should be examined.
                               II
   The plurality accurately describes some aspects of the
history of military commissions and the prerequisites for
their use. Thus, I do not dispute that military commis
sions have historically been “used in three [different]
situations,” ante, at 31–32, and that the only situation
relevant to the instant case is the use of military commis
sions “ ‘to seize and subject to disciplinary measures those
enemies who . . . have violated the law of war,’ ” ante, at 32
(quoting Quirin, supra, at 28–29). Similarly, I agree with
the plurality that Winthrop’s treatise sets forth the four
relevant considerations for determining the scope of a
military commission’s jurisdiction, considerations relating
to the (1) time and (2) place of the offense, (3) the status of
the offender, and (4) the nature of the offense charged.
Winthrop 836–840. The Executive has easily satisfied
these considerations here. The plurality’s contrary con
clusion rests upon an incomplete accounting and an un
faithful application of those considerations.
                 Cite as: 548 U. S. ____ (2006)            7

                    THOMAS, J., dissenting

                               A
   The first two considerations are that a law-of-war mili
tary commission may only assume jurisdiction of “offences
committed within the field of the command of the conven
ing commander,” and that such offenses “must have been
committed within the period of the war.” See id., at 836,
837; ante, at 33. Here, as evidenced by Hamdan’s charg
ing document, the Executive has determined that the
theater of the present conflict includes “Afghanistan,
Pakistan and other countries” where al Qaeda has estab
lished training camps, App. to Pet. for Cert. 64a, and that
the duration of that conflict dates back (at least) to Usama
bin Laden’s August 1996 “Declaration of Jihad Against the
Americans,” ibid. Under the Executive’s description of the
conflict, then, every aspect of the charge, which alleges
overt acts in “Afghanistan, Pakistan, Yemen and other
countries” taking place from 1996 to 2001, satisfies the
temporal and geographic prerequisites for the exercise of
law-of-war military commission jurisdiction. Id., at 65a–
67a. And these judgments pertaining to the scope of the
theater and duration of the present conflict are committed
solely to the President in the exercise of his commander-
in-chief authority. See Prize Cases, 2 Black, at 670 (con
cluding that the President’s commander-in-chief judgment
about the nature of a particular conflict was “a question to
be decided by him, and this Court must be governed by the
decisions and acts of the political department of the Gov
ernment to which this power was entrusted”).
   Nevertheless, the plurality concludes that the legality of
the charge against Hamdan is doubtful because “Hamdan
is charged not with an overt act for which he was caught
redhanded in a theater of war . . . but with an agreement
the inception of which long predated . . . the [relevant
armed conflict].” Ante, at 48 (emphasis in original). The
plurality’s willingness to second-guess the Executive’s judg
ments in this context, based upon little more than its un
8                      HAMDAN v. RUMSFELD

                         THOMAS, J., dissenting

supported assertions, constitutes an unprecedented depar
ture from the traditionally limited role of the courts with
respect to war and an unwarranted intrusion on executive
authority. And even if such second-guessing were appropri
ate, the plurality’s attempt to do so is unpersuasive.
   As an initial matter, the plurality relies upon the date of
the AUMF’s enactment to determine the beginning point
for the “period of the war,” Winthrop 836, thereby suggest
ing that petitioner’s commission does not have jurisdiction
to try him for offenses committed prior to the AUMF’s
enactment. Ante, at 34–36, 48. But this suggestion be
trays the plurality’s unfamiliarity with the realities of
warfare and its willful blindness to our precedents. The
starting point of the present conflict (or indeed any con
flict) is not determined by congressional enactment, but
rather by the initiation of hostilities. See Prize Cases,
supra, at 668 (recognizing that war may be initiated by
“invasion of a foreign nation,” and that such initiation, and
the President’s response, usually precedes congressional
action). Thus, Congress’ enactment of the AUMF did not
mark the beginning of this Nation’s conflict with al Qaeda,
but instead authorized the President to use force in the
midst of an ongoing conflict. Moreover, while the Presi
dent’s “war powers” may not have been activated until the
AUMF was passed, ante, 35, n. 31, the date of such activa
tion has never been used to determine the scope of a mili
tary commission’s jurisdiction.3 Instead, the traditional
——————
   3 Even if the formal declaration of war were generally the determina

tive act in ascertaining the temporal reach of the jurisdiction of a
military commission, the AUMF itself is inconsistent with the plural
ity’s suggestion that such a rule is appropriate in this case. See ante, at
34–36, 48. The text of the AUMF is backward looking, authorizing the
use of “all necessary and appropriate force against those nations,
organizations, or persons he determines planned, authorized, commit
ted, or aided the terrorist attacks that occurred on September 11,
2001.” Thus, the President’s decision to try Hamdan by military
commission—a use of force authorized by the AUMF—for Hamdan’s
                     Cite as: 548 U. S. ____ (2006)                     9

                         THOMAS, J., dissenting

rule is that “[o]ffenses committed before a formal declara
tion of war or before the declaration of martial law may be
tried by military commission.” Green, The Military Com
mission, 42 Am. J. Int’l L. 832, 848 (1948) (hereinafter
Green); see also C. Howland, Digest of Opinions of the
Judge-Advocates General of the Army 1067 (1912) (here
inafter Howland) (“A military commission . . . exercising
. . . jurisdiction . . . under the laws of war . . . may take
cognizance of offenses committed, during the war, before
the initiation of the military government or martial law”
(emphasis in original));4 cf. Yamashita, 327 U. S., at 13
(“The extent to which the power to prosecute violations of
the law of war shall be exercised before peace is declared
rests, not with the courts, but with the political branch of
the Government”). Consistent with this principle, on facts
virtually identical to those here, a military commission
tried Julius Otto Kuehn for conspiring with Japanese
officials to betray the United States Fleet to the Imperial
Japanese Government prior to its attack on Pearl Harbor.
Green 848.5
——————
involvement with al Qaeda prior to September 11, 2001, fits comforta
bly within the framework of the AUMF. In fact, bringing the Septem
ber 11 conspirators to justice is the primary point of the AUMF. By
contrast, on the plurality’s logic, the AUMF would not grant the Presi
dent the authority to try Usama bin Laden himself for his involvement
in the events of September 11, 2001.
   4 The plurality suggests these authorities are inapplicable because

nothing in its “analysis turns on the admitted absence of either a
formal declaration of war or a declaration of martial law. Our focus
instead is on the . . . AUMF.” Ante, at 35, n. 31. The difference identi
fied by the plurality is purely semantic. Both Green and Howland
confirm that the date of the enactment that establishes a legal basis for
forming military commissions—whether it be a declaration of war, a
declaration of martial law, or an authorization to use military force—
does not limit the jurisdiction of military commissions to offenses
committed after that date.
   5 The plurality attempts to evade the import of this historical example

by observing that Kuehn was tried before a martial law commission for
10                       HAMDAN v. RUMSFELD

                           THOMAS, J., dissenting

  Moreover, the President’s determination that the pre
sent conflict dates at least to 1996 is supported by over
whelming evidence. According to the State Department,
al Qaeda declared war on the United States as early as
August 1996. See Dept. of State Fact Sheet: Usama bin
Ladin (Aug. 21, 1998); Dept. of State Fact Sheet: The
Charges against International Terrorist Usama Bin Laden
(Dec. 20, 2000); cf. Prize Cases, 2 Black, at 668 (recogniz
ing that a state of war exists even if “the declaration of it
be unilateral” (emphasis in original)). In February 1998,
al Qaeda leadership issued another statement ordering
the indiscriminate—and, even under the laws of war as
applied to legitimate nation-states, plainly illegal—killing
of American civilians and military personnel alike. See
Jihad Against Jews and Crusaders: World Islamic Front
——————
a violation of federal espionage statutes. Ibid. As an initial matter, the
fact that Kuehn was tried before a martial law commission for an
offense committed prior to the establishment of martial law provides
strong support for the President’s contention that he may try Hamdan
for offenses committed prior to the enactment of the AUMF. Here the
AUMF serves the same function as the declaration of martial law in
Hawaii in 1941, establishing legal authority for the constitution of
military commissions. Moreover, Kuehn was not tried and punished
“by statute, but by the laws and usages of war.” United States v.
Bernard Julius Otto Kuehn, Board of Review 5 (Office of the Military
Governor, Hawaii 1942). Indeed, in upholding the imposition of the
death penalty, a sentence “not authorized by the Espionage statutes,”
ibid., Kuehn’s Board of Review explained that “[t]he fact that persons
may be tried and punished . . . by a military commission for committing
acts defined as offenses by . . . federal statutes does not mean that such
persons are being tried for violations of such . . . statutes; they are,
instead, being tried for acts made offenses only by orders of the . . .
commanding general.” Id., at 6. Lastly, the import of this example is
not undermined by Duncan v. Kahanamoku, 327 U. S. 304 (1946). The
question before the Court in that case involved only whether “loyal
civilians in loyal territory should have their daily conduct governed by
military orders,” id., at 319; it did “not involve the well-established power
of the military to exercise jurisdiction over . . . enemy belligerents,” id., at
313.
                  Cite as: 548 U. S. ____ (2006)            11

                     THOMAS, J., dissenting

Statement 2 (Feb. 23, 1998), in Y. Alexander & M. Swet
nam, Usama bin Laden’s al-Qaida: Profile of a Terrorist
Network, App. 1B (2001) (“The ruling to kill the Ameri
cans and their allies—civilians and military—is an indi
vidual duty for every Muslim who can do it in any country
in which it is possible to do it”). This was not mere rheto
ric; even before September 11, 2001, al Qaeda was in
volved in the bombing of the World Trade Center in New
York City in 1993, the bombing of the Khobar Towers in
Saudi Arabia in 1996, the bombing of the U. S. Embassies
in Kenya and Tanzania in 1998, and the attack on the
U. S. S. Cole in Yemen in 2000. See id., at 1. In response
to these incidents, the United States “attack[ed] facilities
belonging to Usama bin Ladin’s network” as early as 1998.
Dept. of State Fact Sheet: Usama bin Ladin (Aug. 21,
1998). Based on the foregoing, the President’s judgment—
that the present conflict substantially predates the AUMF,
extending at least as far back as al Qaeda’s 1996 declara
tion of war on our Nation, and that the theater of war
extends at least as far as the localities of al Qaeda’s prin
cipal bases of operations—is beyond judicial reproach.
And the plurality’s unsupportable contrary determination
merely confirms that “ ‘the Judiciary has neither aptitude,
facilities nor responsibility’ ” for making military or foreign
affairs judgments. Hamdi, 542 U. S., at 585 (THOMAS, J.,
dissenting) (quoting Chicago & Southern Air Lines, 333
U. S., at 111).
                             B
  The third consideration identified by Winthrop’s treatise
for the exercise of military commission jurisdiction per
tains to the persons triable before such a commission, see
ante, at 33; Winthrop 838. Law-of-war military commis
sions have jurisdiction over “ ‘individuals of the enemy’s
army who have been guilty of illegitimate warfare or other
offences in violation of the laws of war,’ ” ante, at 33-34
12                 HAMDAN v. RUMSFELD

                    THOMAS, J., dissenting

(quoting Winthrop 838). They also have jurisdiction over
“[i]rregular armed bodies or persons not forming part of
the organized forces of a belligerent” “who would not be
likely to respect the laws of war.” Id., at 783, 784. Indeed,
according to Winthrop, such persons are not “within the
protection of the laws of war” and were “liable to be shot,
imprisoned, or banished, either summarily where their
guilt was clear or upon trial and conviction by military
commission.” Id., at 784. This consideration is easily satis
fied here, as Hamdan is an unlawful combatant charged
with joining and conspiring with a terrorist network dedi
cated to flouting the laws of war. 344 F. Supp. 2d 152, 161
(DC 2004); App. to Pet. for Cert. 63a–67a.
                              C
   The fourth consideration relevant to the jurisdiction of
law-of-war military commissions relates to the nature of
the offense charged. As relevant here, such commissions
have jurisdiction to try “ ‘[v]iolations of the laws and us
ages of war cognizable by military tribunals only,’ ” ante,
at 34 (quoting Winthrop 839). In contrast to the preceding
considerations, this Court’s precedents establish that
judicial review of “whether any of the acts charged is an
offense against the law of war cognizable before a military
tribunal” is appropriate. Quirin, 317 U. S., at 29. How
ever, “charges of violations of the law of war triable before
a military tribunal need not be stated with the precision of
a common law indictment.” Yamashita, 327 U. S., at 17.
And whether an offense is a violation of the law of war
cognizable before a military commission must be deter
mined pursuant to “the system of common law applied by
military tribunals.” Quirin, supra, at 30; Yamashita,
supra, at 8.
   The common law of war as it pertains to offenses triable
by military commission is derived from the “experience of
our wars” and our wartime tribunals, Winthrop 839, and
                 Cite as: 548 U. S. ____ (2006)          13

                    THOMAS, J., dissenting

“the laws and usages of war as understood and practiced
by the civilized nations of the world,” 11 Op. Atty. Gen.
297, 310 (1865). Moreover, the common law of war is
marked by two important features. First, as with the
common law generally, it is flexible and evolutionary in
nature, building upon the experience of the past and
taking account of the exigencies of the present. Thus,
“[t]he law of war, like every other code of laws, declares
what shall not be done, and does not say what may be
done. The legitimate use of the great power of war, or
rather the prohibitions upon the use of that power, in
crease or diminish as the necessity of the case demands.”
Id., at 300. Accordingly, this Court has recognized that
the “jurisdiction” of “our common-law war courts” has not
been “prescribed by statute,” but rather “has been adapted
in each instance to the need that called it forth.” Madsen,
343 U. S., at 346–348. Second, the common law of war
affords a measure of respect for the judgment of military
commanders. Thus, “[t]he commander of an army in time
of war has the same power to organize military tribunals
and execute their judgments that he has to set his squad
rons in the field and fight battles. His authority in each
case is from the law and usage of war.” 11 Op. Atty. Gen.,
at 305. In recognition of these principles, Congress has
generally “ ‘left it to the President, and the military com
manders representing him, to employ the commission, as
occasion may require, for the investigation and punish
ment of violations of the law of war.’ ” Madsen, supra, at
347, n. 9 (quoting Winthrop 831; emphasis added).
   In one key respect, the plurality departs from the proper
framework for evaluating the adequacy of the charge
against Hamdan under the laws of war. The plurality
holds that where, as here, “neither the elements of the
offense nor the range of permissible punishments is de
fined by statute or treaty, the precedent [establishing
whether an offense is triable by military commission]
14                     HAMDAN v. RUMSFELD

                         THOMAS, J., dissenting

must be plain and unambiguous.” Ante, at 38. This is a
pure contrivance, and a bad one at that. It is contrary to
the presumption we acknowledged in Quirin, namely, that
the actions of military commissions are “not to be set aside
by the courts without the clear conviction that they are”
unlawful, 317 U. S., at 25 (emphasis added). It is also
contrary to Yamashita, which recognized the legitimacy of
that military commission notwithstanding a substantial
disagreement pertaining to whether Yamashita had been
charged with a violation of the law of war. Compare 327
U. S., at 17 (noting that the allegations were “adequat[e]”
and “need not be stated with . . . precision”), with id., at 35
(Murphy, J., dissenting) (arguing that the charge was
inadequate). Nor does it find support from the separation
of powers authority cited by the plurality. Indeed, Madi
son’s praise of the separation of powers in The Federalist
No. 47, quoted ante, at 38-39, if it has any relevance at all,
merely highlights the illegitimacy of today’s judicial intru
sion onto core executive prerogatives in the waging of war,
where executive competence is at its zenith and judicial
competence at its nadir.
  The plurality’s newly minted clear-statement rule is also
fundamentally inconsistent with the nature of the common
law which, by definition, evolves and develops over time
and does not, in all cases, “say what may be done.” 11 Op.
Atty. Gen., at 300. Similarly, it is inconsistent with the
nature of warfare, which also evolves and changes over
time, and for which a flexible, evolutionary common-law
system is uniquely appropriate.6 Though the charge
——————
  6 Indeed, respecting the present conflict, the President has found that

“the war against terrorism ushers in a new paradigm, one in which
groups with broad, international reach commit horrific acts against
innocent civilians, sometimes with the direct support of states. Our
Nation recognizes that this new paradigm—ushered in not by us, but
by terrorists—requires new thinking in the law of war.” App. 34–35.
Under the Court’s approach, the President’s ability to address this “new
                      Cite as: 548 U. S. ____ (2006)                    15

                         THOMAS, J., dissenting

against Hamdan easily satisfies even the plurality’s
manufactured rule, see supra, at 16–28, the plurality’s
inflexible approach has dangerous implications for the
Executive’s ability to discharge his duties as Commander
in Chief in future cases. We should undertake to deter
mine whether an unlawful combatant has been charged
with an offense against the law of war with an under
standing that the common law of war is flexible, respon
sive to the exigencies of the present conflict, and deferen
tial to the judgment of military commanders.
                              1
   Under either the correct, flexible approach to evaluating
the adequacy of Hamdan’s charge, or under the plurality’s
new, clear-statement approach, Hamdan has been charged
with conduct constituting two distinct violations of the law
of war cognizable before a military commission: member
ship in a war-criminal enterprise and conspiracy to com
mit war crimes. The charging section of the indictment
alleges both that Hamdan “willfully and knowingly joined
an enterprise of persons who shared a common criminal
purpose,” App. to Pet. for Cert. 65a, and that he “conspired
and agreed with [al Qaeda] to commit . . . offenses triable
by military commission,” ibid.7
——————
paradigm” of inflicting death and mayhem would be completely frozen
by rules developed in the context of conventional warfare.
  7 It is true that both of these separate offenses are charged under a

single heading entitled “CHARGE: CONSPIRACY,” App. to Pet. for
Cert. 65a. But that does not mean that they must be treated as a single
crime, when the law of war treats them as separate crimes. As we
acknowledged in In re Yamashita, 327 U. S. 1 (1946), “charges of
violations of the law of war triable before a military tribunal need not
be stated with the precision of a common law indictment.” Id., at 17; cf.
W. Birkhimer, Military Government and Martial Law 536 (3d ed. 1914)
(hereinafter Birkhimer) (“[I]t would be extremely absurd to expect the
same precision in a charge brought before a court-martial as is required to
support a conviction before a justice of the peace” (internal quotation
marks omitted)).
16                     HAMDAN v. RUMSFELD

                         THOMAS, J., dissenting

   The common law of war establishes that Hamdan’s
willful and knowing membership in al Qaeda is a war
crime chargeable before a military commission. Hamdan,
a confirmed enemy combatant and member or affiliate of
al Qaeda, has been charged with willfully and knowingly
joining a group (al Qaeda) whose purpose is “to support
violent attacks against property and nationals (both mili
tary and civilian) of the United States.” Id., at 64a; 344 F.
Supp. 2d, at 161. Moreover, the allegations specify that
Hamdan joined and maintained his relationship with al
Qaeda even though he “believed that Usama bin Laden
and his associates were involved in the attacks on the
U. S. Embassies in Kenya and Tazania in August 1998,
the attack on the USS COLE in October 2000, and the
——————
   Nevertheless, the plurality contends that Hamdan was “not actually
charged,” ante, at 37, n. 32 (emphasis deleted), with being a member in
a war criminal organization. But that position is demonstrably wrong.
Hamdan’s charging document expressly charges that he “willfully and
knowingly joined an enterprise of persons who shared a common
criminal purpose.” App. to Pet. for Cert. 65a. Moreover, the plurality’s
contention that we may only look to the label affixed to the charge to
determine if the charging document alleges an offense triable by
military commission is flatly inconsistent with its treatment of the Civil
War cases—where it accepts as valid charges that did not appear in the
heading or title of the charging document, or even the listed charge
itself, but only in the supporting specification. See, e.g., ante, at 45–46
(discussing the military commission trial of Wirz). For example, in the
Wirz case, Wirz was charged with conspiring to violate the laws of war,
and that charge was supported with allegations that he personally
committed a number of atrocities. The plurality concludes that military
commission jurisdiction was appropriate in that case not based upon
the charge of conspiracy, but rather based upon the allegations of
various atrocities in the specification which were not separately
charged. Ante, at 45. Just as these atrocities, not separately charged,
were independent violations of the law of war supporting Wirz’s trial by
military commission, so too here Hamdan’s membership in al Qaeda
and his provision of various forms of assistance to al Qaeda’s top
leadership are independent violations of the law of war supporting his
trial by military commission.
                     Cite as: 548 U. S. ____ (2006)                   17

                         THOMAS, J., dissenting

attacks on the United States on September 11, 2001.”
App. to Pet. for Cert. 65a. These allegations, against a
confirmed unlawful combatant, are alone sufficient to
sustain the jurisdiction of Hamdan’s military commission.
  For well over a century it has been established that “to
unite with banditti, jayhawkers, guerillas, or any other
unauthorized marauders is a high offence against the laws
of war; the offence is complete when the band is organized
or joined. The atrocities committed by such a band do not
constitute the offence, but make the reasons, and sufficient
reasons they are, why such banditti are denounced by the
laws of war.” 11 Op. Atty. Gen., at 312 (emphasis added).8
In other words, unlawful combatants, such as Hamdan,
violate the law of war merely by joining an organization,
such as al Qaeda, whose principal purpose is the “killing
[and] disabling . . . of peaceable citizens or soldiers.”
Winthrop 784; see also 11 Op. Atty. Gen., at 314 (“A bush
whacker, a jayhawker, a bandit, a war rebel, an assassin,
being public enemies, may be tried, condemned, and exe
cuted as offenders against the laws of war”). This conclu
sion is unsurprising, as it is a “cardinal principle of the
law of war . . . that the civilian population must enjoy
complete immunity.” 4 International Committee of Red
Cross, Commentary: Geneva Convention Relative to the
——————
   8 These observations respecting the law of war were made by the

Attorney General in defense of the military commission trial of the
Lincoln conspirators’. As the foregoing quoted portion of that opinion
makes clear, the Attorney General did not, as the Court maintains,
“trea[t] the charge as if it alleged the substantive offense of assassina
tion.” Ante, at 40, n. 35. Rather, he explained that the conspirators
“high offence against the laws of war” was “complete” when their band
was “organized or joined,” and did not depend upon “atrocities commit
ted by such a band.” 11 Op. Atty. Gen. 297, 312 (1865). Moreover, the
Attorney General’s conclusions specifically refute the plurality’s unsup
ported suggestion that I have blurred the line between “those categories
of ‘offender’ who may be tried by military commission . . . with the
‘offenses’ that may be so tried.” Ante, at 37, n. 32.
18                      HAMDAN v. RUMSFELD

                          THOMAS, J., dissenting

Protection of Civilian Persons in Time of War 3 (J. Pictet
ed. 1958). “Numerous instances of trials, for ‘Violation of
the laws of war,’ of offenders of this description, are pub
lished in the General Orders of the years 1862 to 1866.”
Winthrop 784, and n. 57.9 Accordingly, on this basis
——————
   9 The General Orders establishing the jurisdiction for military com

missions during the Civil War provided that such offenses were viola
tions of the laws of war cognizable before military commissions. See
H. R. Doc. No. 65, 55th Cong., 3d Sess., 164 (1894) (“[P]ersons charged
with the violation of the laws of war as spies, bridge-burners, maraud
ers, &c., will . . . be held for trial under such charges”); id., at 234
(“[T]here are numerous rebels . . . that . . . furnish the enemy with
arms, provisions, clothing, horses and means of transportation; [such]
insurgents are banding together in several of the interior counties for
the purpose of assisting the enemy to rob, to maraud and to lay waste
to the country. All such persons are by the laws of war in every civilized
country liable to capital punishment” (emphasis added)). Numerous
trials were held under this authority. See, e.g., U. S. War Dept.,
General Court-Martial Order No. 51, p. 1 (1866) (hereinafter
G. C. M. O.). (indictment in the military commission trial of James
Harvey Wells charged “[b]eing a guerrilla” and specified that he “will
fully . . . [took] up arms as a guerrilla marauder, and did join, belong to,
act and co-operate with guerrillas”); G. C. M. O. No. 108, Head-
Quarters Dept. of Kentucky, p. 1 (1865) (indictment in the military
commission trial of Henry C. Magruder charged “[b]eing a guerrilla”
and specified that he “unlawfully, and of his own wrong, [took] up arms
as a guerrilla marauder, and did join, belong to, act, and co-operate
with a band of guerrillas”); G. C. M. O. No. 41, p. 1 (1864) (indictment
in the military commission trial of John West Wilson charged that
Wilson “did take up arms as an insurgent and guerrilla against the
laws and authorities of the United States, and did join and co-operate
with an armed band of insurgents and guerrillas who were engaged in
plundering the property of peaceable citizens . . . in violation of the laws
and customs of war”); G. C. M. O. No. 153, p. 1 (1864) (indictment in the
military commission trial of Simeon B. Kight charged that defendant
was “a guerrilla, and has been engaged in an unwarrantable and
barbarous system of warfare against citizens and soldiers of the United
States”); G. C. M. O. No. 93, pp. 3–4 (1864) (indictment in the military
commission trial of Francis H. Norvel charged “[b]eing a guerrilla” and
specified that he “unlawfully and by his own wrong, [took] up arms as
an outlaw, guerrilla, and bushwhacker, against the lawfully constituted
                     Cite as: 548 U. S. ____ (2006)                   19

                         THOMAS, J., dissenting

alone, “the allegations of [Hamdan’s] charge, tested by any
reasonable standard, adequately allege a violation of the
law of war.” Yamashita, 327 U. S., at 17.
   The conclusion that membership in an organization
whose purpose is to violate the laws of war is an offense
triable by military commission is confirmed by the experi
ence of the military tribunals convened by the United
States at Nuremberg. Pursuant to Article 10 of the Char
ter of the International Military Tribunal (IMT), the
United States convened military tribunals “to bring indi
viduals to trial for membership” in “a group or organiza
tion . . . declared criminal by the [IMT].” 1 Trials of War
Criminals Before the Nuernberg Military Tribunals, p. XII
(hereinafter Trials). The IMT designated various compo
nents of four Nazi groups—the Leadership Corps, Ge
stapo, SD, and SS—as criminal organizations. 22 IMT,
Trial of the Major War Criminals 505, 511, 517 (1948); see
also T. Taylor, The Anatomy of the Nuremberg Trials: A
Personal Memoir 584–585 (1992). “[A] member of [such]
an organization [could] be . . . convicted of the crime of
membership and be punished for that crime by death.” 22
IMT, at 499. Under this authority, the United States
Military Tribunal at Nuremberg convicted numerous
individuals for the act of knowing and voluntary member
ship in these organizations. For example, in Military
Tribunal Case No. 1, United States v. Brandt, Karl
Brandt, Karl Gebhardt, Rudolf Brandt, Joachim
——————
authorities of the United States government”); id., at 9 (indictment in
the military commission trial of James A. Powell charged
“[t]ransgression of the laws and customs of war” and specified that he
“[took] up arms in insurrection as a military insurgent, and did join
himself to and, in arms, consort with . . . a rebel enemy of the United
States, and the leader of a band of insurgents and armed rebels”); id.,
at 10–11 (indictment in the military commission trial of Joseph
Overstreet charged “[b]eing a guerrilla” and specified that he “did join,
belong to, consort and co-operate with a band of guerrillas, insurgents,
outlaws, and public robbers”).
20                    HAMDAN v. RUMSFELD

                        THOMAS, J., dissenting

Mrugowsky, Wolfram Sievers, Viktor Brack, and Walde
mar Hoven, were convicted and sentenced to death for the
crime of, inter alia, membership in an organization de
clared criminal by the IMT; Karl Genzken and Fritz
Fischer were sentenced to life imprisonment for the same;
and Helmut Poppendick was convicted of no other offense
than membership in a criminal organization and sen
tenced to a 10-year term of imprisonment. 2 Trials 180–
300. This Court denied habeas relief, 333 U. S. 836
(1948), and the executions were carried out at Landsberg
prison on June 2, 1948. 2 Trials 330.
    Moreover, the Government has alleged that Hamdan
was not only a member of al Qaeda while it was carrying
out terrorist attacks on civilian targets in the United
States and abroad, but also that Hamdan aided and as
sisted al Qaeda’s top leadership by supplying weapons,
transportation, and other services. App. to Pet. for Cert.
65a–67a. These allegations further confirm that Hamdan
is triable before a law-of-war military commission for his
involvement with al Qaeda. See H. R. Doc. No. 65, 55th
Cong., 3d Sess., 234 (1894) (“[T]here are numerous rebels
. . . that . . . furnish the enemy with arms, provisions,
clothing, horses and means of transportation; [such] in
surgents are banding together in several of the interior
counties for the purpose of assisting the enemy to rob, to
maruad and to lay waste to the country. All such persons
are by the laws of war in every civilized country liable to
capital punishment” (emphasis added)); Winthrop 840
(including in the list of offenses triable by law-of-war
military commissions “dealing with . . . enemies, or fur
nishing them with money, arms, provisions, medicines,
&c”).10 Undoubtedly, the conclusion that such conduct
——————
  10 Even if the plurality were correct that a membership offense must

be accompanied by allegations that the “defendant ‘took up arms,’ ”
ante, at 37, n. 32, that requirement has easily been satisfied here. Not
                    Cite as: 548 U. S. ____ (2006)                  21

                        THOMAS, J., dissenting

violates the law of war led to the enactment of Article 104
of the UCMJ, which provides that “[a]ny person who . . .
aids, or attempts to aid, the enemy with arms, ammuni
tion, supplies, money, or other things . . . shall suffer
death or such other punishment as a court-martial or
military commission may direct.” 10 U. S. C. §904.
                              2
   Separate and apart from the offense of joining a contin
gent of “uncivilized combatants who [are] not . . . likely to
respect the laws of war,” Winthrop 784, Hamdan has been
charged with “conspir[ing] and agree[ing] with . . . the al
Qaida organization . . . to commit . . . offenses triable by
military commission,” App. to Pet. for Cert. 65a. Those
offenses include “attacking civilians; attacking civilian
objects; murder by an unprivileged belligerent; and terror
ism.” Ibid. This, too, alleges a violation of the law of war
triable by military commission.
   “[T]he experience of our wars,” Winthrop 839, is rife
with evidence that establishes beyond any doubt that
conspiracy to violate the laws of war is itself an offense
cognizable before a law-of-war military commission.
World War II provides the most recent examples of the use
of American military commissions to try offenses pertain
ing to violations of the laws of war. In that conflict, the
orders establishing the jurisdiction of military commis
sions in various theaters of operation provided that con
spiracy to violate the laws of war was a cognizable offense.
See Letter, General Headquarters, United States Army
Forces, Pacific (Sept. 24, 1945), Record in Yamashita v.
Styer, O. T. 1945, No. 672, pp. 14, 16 (Exh. F) (Order
respecting the “Regulations Governing the Trial of War
——————
only has Hamdan been charged with providing assistance to top al
Qaeda leadership (itself an offense triable by military commission), he
has also been charged with receiving weapons training at an al Qaeda
camp. App. to Pet. for Cert. 66a–67a.
22                     HAMDAN v. RUMSFELD

                         THOMAS, J., dissenting

Criminals” provided that “participation in a common plan
or conspiracy to accomplish” various offenses against the
law of war was cognizable before military commissions); 1
United Nations War Crimes Commission, Law Reports of
Trials of War Criminals 114–115 (1997) (hereinafter U. N.
Commission) (recounting that the orders establishing
World War II military commissions in the Pacific and
China included “participation in a common plan or con
spiracy” pertaining to certain violations of the laws of war
as an offense triable by military commission). Indeed,
those orders authorized trial by military commission of
participation in a conspiracy to commit “murder . . . or
other inhumane acts . . . against any civilian population,”
id., at 114, which is precisely the offense Hamdan has
been charged with here. And conspiracy to violate the
laws of war was charged in the highest profile case tried
before a World War II military commission, see Quirin,
317 U. S., at 23, and on numerous other occasions. See,
e.g., Colepaugh v. Looney, 235 F. 2d 429, 431 (CA10 1956);
Green 848 (describing the conspiracy trial of Julius Otto
Kuehn).
   To support its contrary conclusion, ante, at 35–36, the
plurality attempts to evade the import of Quirin (and the
other World War II authorities) by resting upon this
Court’s failure to address the sufficiency of the conspiracy
charge in the Quirin case, ante, at 41–43. But the com
mon law of war cannot be ascertained from this Court’s
failure to pass upon an issue, or indeed to even mention
the issue in its opinion;11 rather, it is ascertained by the
practice and usage of war. Winthrop 839; supra, at 11–12.
——————
  11 The plurality recounts the respective claims of the parties in Quirin

pertaining to this issue and cites the United States Reports. Ante, at
41-42. But the claims of the parties are not included in the opinion of
the Court, but rather in the sections of the Reports entitled “Argument
for Petitioners,” and “Argument for Respondent.” See 317 U. S., at
6–17.
                     Cite as: 548 U. S. ____ (2006)                   23

                         THOMAS, J., dissenting

   The Civil War experience provides further support for
the President’s conclusion that conspiracy to violate the
laws of war is an offense cognizable before law-of-war
military commissions. Indeed, in the highest profile case
to be tried before a military commission relating to that
war, namely, the trial of the men involved in the assassi
nation of President Lincoln, the charge provided that those
men had “combin[ed], confederat[ed], and conspir[ed] . . . to
kill and murder” President Lincoln. G. C. M. O. No. 356
(1865), reprinted in H. R. Doc. No. 314, 55th Cong., 3d
Sess., 696 (1899) (hereinafter G. C. M. O. No. 356).12
   In addition to the foregoing high-profile example, Win
throp’s treatise enumerates numerous Civil War military
commission trials for conspiracy to violate the law of war.
Winthrop 839, n. 5. The plurality attempts to explain
these examples away by suggesting that the conspiracies
listed by Winthrop are best understood as “a species of
——————
   12 The plurality concludes that military commission jurisdiction was

appropriate in the case of the Lincoln conspirators because they were
charged with “ ‘maliciously, unlawfully, and traitorously murdering the
said Abraham Lincoln,’ ” ante, at 40, n. 35. But the sole charge filed in
that case alleged conspiracy, and the allegations pertaining to “mali
ciously, unlawfully, and traitorously murdering the said Abraham
Lincoln” were not charged or labeled as separate offenses, but rather as
overt acts “in pursuance of and in prosecuting said malicious, unlawful,
and traitorous conspiracy. ” G. C. M. O. No. 356, at ___ (emphasis
added). While the plurality contends the murder of President Lincoln
was charged as a distinct separate offense, the foregoing quoted lan
guage of the charging document unequivocally establishes otherwise.
Moreover, though I agree that the allegations pertaining to these overt
acts provided an independent basis for the military commission’s
jurisdiction in that case, that merely confirms the propriety of examin
ing all the acts alleged—whether or not they are labeled as separate
offenses—to determine if a defendant has been charged with a violation
of the law of war. As I have already explained, Hamdan has been
charged with violating the law of war not only by participating in a
conspiracy to violate the law of war, but also by joining a war criminal
enterprise and by supplying provisions and assistance to that enter
prise’s top leadership.
24                  HAMDAN v. RUMSFELD

                     THOMAS, J., dissenting

compound offense,” namely, violations both of the law of
war and ordinary criminal laws, rather than “stand-alone
offense[s] against the law of war.” Ante, at 44–45 (citing,
as an example, murder in violation of the laws of war).
But the fact that, for example, conspiracy to commit mur
der can at the same time violate ordinary criminal laws
and the law of war, so that it is “a combination of the two
species of offenses,” Howland 1071, does not establish that
a military commission would not have jurisdiction to try
that crime solely on the basis that it was a violation of the
law of war. Rather, if anything, and consistent with the
principle that the common law of war is flexible and af
fords some level of deference to the judgments of military
commanders, it establishes that military commissions
would have the discretion to try the offense as (1) one
against the law of war, or (2) one against the ordinary
criminal laws, or (3) both.
  In any event, the plurality’s effort to avoid the import of
Winthrop’s footnote through the smokescreen of its “com
pound offense” theory, ante, at 44–45, cannot be reconciled
with the particular charges that sustained military com
mission jurisdiction in the cases that Winthrop cites. For
example, in the military commission trial of Henry Wirtz,
Charge I provided that he had been
     “[m]aliciously, willfully, and traitorously . . . combin
     ing, confederating, and conspiring, together [with
     various other named and unnamed co-conspirators],
     to injure the health and destroy the lives of soldiers in
     the military service of the United States, then held
     and being prisoners of war within the lines of the so-
     called Confederate States, and in the military prisons
     thereof, to the end that the armies of the United
     States might be weakened and impaired, in violation
     of the laws and customs of war.” G. C. M. O. No. 607
     (1865), reprinted in H. R. Doc. No. 314, at 785 (em
                      Cite as: 548 U. S. ____ (2006)                    25

                         THOMAS, J., dissenting

     phasis added).
Likewise, in the military commission trial of Lenger
Grenfel, Charge I accused Grenfel of “[c]onspiring, in
violation of the laws of war, to release rebel prisoners of
war confined by authority of the United States at Camp
Douglas, near Chicago, Ill.” G. C. M. O. No. 452 (1865),
reprinted in H. R. Doc. No. 314, at 724 (emphasis added)13;
see also G. C. M. O. No. 41, at 20 (1864) (indictment in the
military commission trial of Robert Louden charged
“[c]onspiring with the rebel enemies of the United States
to embarrass and impede the military authorities in the

——————
  13 The plurality’s attempt to undermine the significance of these cases
is unpersuasive. The plurality suggests the Wirz case is not relevant
because the specification supporting his conspiracy charge alleged that
he “personally committed a number of atrocities.” Ante, at 45. But this
does not establish that conspiracy to violate the laws of war, the very
crime with which Wirz was charged, is not itself a violation of the law
of war. Rather, at best, it establishes that in addition to conspiracy
Wirz violated the laws of war by committing various atrocities, just as
Hamdan violated the laws of war not only by conspiring to do so, but
also by joining al Qaeda and providing provisions and services to its top
leadership. Moreover, the fact that Wirz was charged with overt acts
that are more severe than the overt acts with which Hamdan has been
charged does not establish that conspiracy is not an offense cognizable
before military commission; rather it merely establishes that Wirz’s
offenses may have been comparably worse than Hamdan’s offenses.
   The plurality’s claim that the charge against Lenger Grenfel supports
its compound offense theory is similarly unsupportable. The plurality
does not, and cannot, dispute that Grenfel was charged with conspiring
to violate the laws of war by releasing rebel prisoners—a charge that
bears no relation to a crime “ordinarily triable in civilian courts.” Ante,
at 46, n. 37. Tellingly, the plurality does not reference or discuss this
charge, but instead refers to the conclusion of Judge Advocate Holt that
Grenfel also “ ‘united himself with traitors and malefactors for the
overthrow of our Republic in the interest of slavery.’ ” Ibid. (quoting
H. R. Doc. No. 314, at 689). But Judge Advocate Holt’s observation
provides no support for the plurality’s conclusion, as it does not discuss
the charges that sustained military commission jurisdiction, much less
suggest that such charges were not violations of the law of war.
26                     HAMDAN v. RUMSFELD

                         THOMAS, J., dissenting

suppression of the existing rebellion, by the burning and
destruction of steamboats and means of transportation on
the Mississippi river”). These examples provide incontro
vertible support for the President’s conclusion that the
common law of war permits military commission trials for
conspiracy to violate the law of war. And they specifically
contradict the plurality’s conclusion to the contrary,
thereby easily satisfying its requirement that the Gov
ernment “make a substantial showing that the crime for
which it seeks to try a defendant by military commission
is acknowledged to be an offense against the law of war.”
Ante, at 39-40.14
   The plurality further contends, in reliance upon Win

——————
   14 The plurality contends that international practice—including the

practice of the IMT at Nuremberg—supports its conclusion that con
spiracy is not an offense triable by military commission because “ ‘[t]he
Anglo-American concept of conspiracy was not part of European legal
systems and arguably not an element of the internationally recognized
laws of war.’ ” Ante, at 47 (quoting T. Taylor, Anatomy of the Nurem
berg Trials: A Personal Memoir 36 (1992)). But while the IMT did not
criminalize all conspiracies to violate the law of war, it did criminalize
“participation in a common plan or conspiracy” to wage aggressive war.
See 1 Trials, pp. XI–XII. Moreover, the World War II military tribunals
of several European nations recognized conspiracy to violate the laws of
war as an offense triable before military commissions. See 15 U. N.
Commission 90–91 (noting that the French Military Tribunal at Mar
seilles found Henri Georges Stadelhofer “guilty of the crime of associa
tion de malfaiteurs,” namely of “having formed with various members of
the German Gestapo an association with the aim of preparing or
committing crimes against persons or property, without justification
under the laws and usages of war”); 11 id., at 98 (noting that the
Netherlands’ military tribunals were authorized to try conspiracy to
violate the laws of war). Thus, the European legal systems’ approach to
domestic conspiracy law has not prevented European nations from
recognizing conspiracy offenses as violations of the law of war. This is
unsurprising, as the law of war is derived not from domestic law but
from the wartime practices of civilized nations, including the United
States, which has consistently recognized that conspiracy to violate the
laws of war is an offense triable by military commission.
                  Cite as: 548 U. S. ____ (2006)            27

                     THOMAS, J., dissenting

throp, that conspiracy is not an offense cognizable before a
law-of-war military commission because “it is not enough
to intend to violate the law of war and commit overt acts
in furtherance of that intention unless the overt acts
either are themselves offenses against the law of war or
constitute steps sufficiently substantial to qualify as an
attempt.” Ibid. But Winthrop does not support the plural
ity’s conclusion. The passage in Winthrop cited by the
plurality states only that “the jurisdiction of the military
commission should be restricted to cases of offence consist
ing in overt acts, i.e. in unlawful commissions or actual
attempts to commit, and not in intentions merely.” Win
throp 841 (emphasis in original). This passage would be
helpful to the plurality if its subject were “conspiracy,”
rather than the “jurisdiction of the military commission.”
Winthrop is not speaking here of the requirements for a
conspiracy charge, but of the requirements for all charges.
Intentions do not suffice. An unlawful act—such as com
mitting the crime of conspiracy—is necessary. Winthrop
says nothing to exclude either conspiracy or membership
in a criminal enterprise, both of which go beyond “inten
tions merely” and “consis[t] of overt acts, i.e. . . . unlawful
commissions or actual attempts to commit,” and both of
which are expressly recognized by Winthrop as crimes
against the law of war triable by military commissions.
Id., at 784; id., at 839, and n. 5, 840. Indeed, the commis
sion of an “overt ac[t]” is the traditional requirement for
the completion of the crime of conspiracy, and the charge
against Hamdan alleges numerous such overt acts. App.
to Pet. for Cert. 65a. The plurality’s approach, unsup
ported by Winthrop, requires that any overt act to further
a conspiracy must itself be a completed war crime distinct
from conspiracy—which merely begs the question the
plurality sets out to answer, namely, whether conspiracy
itself may constitute a violation of the law of war. And,
even the plurality’s unsupported standard is satisfied
28                 HAMDAN v. RUMSFELD

                    THOMAS, J., dissenting

here. Hamdan has been charged with the overt acts of
providing protection, transportation, weapons, and other
services to the enemy, id., at 65a–67a, acts which in and of
themselves are violations of the laws of war. See supra, at
20–21; Winthrop 839–840.
                               3
   Ultimately, the plurality’s determination that Hamdan
has not been charged with an offense triable before a
military commission rests not upon any historical example
or authority, but upon the plurality’s raw judgment of the
“inability on the Executive’s part here to satisfy the most
basic precondition . . . for establishment of military com
missions: military necessity.” Ante, at 48. This judgment
starkly confirms that the plurality has appointed itself the
ultimate arbiter of what is quintessentially a policy and
military judgment, namely, the appropriate military
measures to take against those who “aided the terrorist
attacks that occurred on September 11, 2001.” AUMF
§2(a), 115 Stat. 224. The plurality’s suggestion that Ham
dan’s commission is illegitimate because it is not dispens
ing swift justice on the battlefield is unsupportable. Ante,
at 43. Even a cursory review of the authorities confirms
that law-of-war military commissions have wide-ranging
jurisdiction to try offenses against the law of war in exi
gent and nonexigent circumstances alike. See, e.g., Win
throp 839–840; see also Yamashita, 327 U. S., at 5 (mili
tary commission trial after the cessation of hostilities in
the Philippines); Quirin, 317 U. S. 1 (military commission
trial in Washington, D. C.). Traditionally, retributive
justice for heinous war crimes is as much a “military
necessity” as the “demands” of “military efficiency” touted
by the plurality, and swift military retribution is precisely
what Congress authorized the President to impose on the
September 11 attackers in the AUMF.
   Today a plurality of this Court would hold that conspir
                 Cite as: 548 U. S. ____ (2006)           29

                    THOMAS, J., dissenting

acy to massacre innocent civilians does not violate the
laws of war. This determination is unsustainable. The
judgment of the political branches that Hamdan, and
others like him, must be held accountable before military
commissions for their involvement with and membership
in an unlawful organization dedicated to inflicting massive
civilian casualties is supported by virtually every relevant
authority, including all of the authorities invoked by the
plurality today. It is also supported by the nature of the
present conflict. We are not engaged in a traditional
battle with a nation-state, but with a worldwide, hydra-
headed enemy, who lurks in the shadows conspiring to
reproduce the atrocities of September 11, 2001, and who
has boasted of sending suicide bombers into civilian gath
erings, has proudly distributed videotapes of beheadings of
civilian workers, and has tortured and dismembered
captured American soldiers. But according to the plural
ity, when our Armed Forces capture those who are plotting
terrorist atrocities like the bombing of the Khobar Towers,
the bombing of the U. S. S. Cole, and the attacks of Sep
tember 11—even if their plots are advanced to the very
brink of fulfillment—our military cannot charge those
criminals with any offense against the laws of war. In
stead, our troops must catch the terrorists “redhanded,”
ante, at 48, in the midst of the attack itself, in order to
bring them to justice. Not only is this conclusion funda
mentally inconsistent with the cardinal principal of the
law of war, namely protecting non-combatants, but it
would sorely hamper the President’s ability to confront
and defeat a new and deadly enemy.
   After seeing the plurality overturn longstanding prece
dents in order to seize jurisdiction over this case, ante, at
2–4 (SCALIA, J., dissenting), and after seeing them disre
gard the clear prudential counsel that they abstain in
these circumstances from using equitable powers, ante, at
19–24, it is no surprise to see them go on to overrule one
30                HAMDAN v. RUMSFELD

                    THOMAS, J., dissenting

after another of the President’s judgments pertaining to
the conduct of an ongoing war. Those Justices who today
disregard the commander-in-chief’s wartime decisions,
only 10 days ago deferred to the judgment of the Corps of
Engineers with regard to a matter much more within the
competence of lawyers, upholding that agency’s wildly
implausible conclusion that a storm drain is a tributary of
the waters of the United States. See Rapanos v. United
States, 547 U. S. ___(2006). It goes without saying that
there is much more at stake here than storm drains. The
plurality’s willingness to second-guess the determination
of the political branches that these conspirators must be
brought to justice is both unprecedented and dangerous.
                             III
  The Court holds that even if “the Government has
charged Hamdan with an offense against the law of war
cognizable by military commission, the commission lacks
power to proceed” because of its failure to comply with the
terms of the UCMJ and the four Geneva Conventions signed
in 1949. Ante, at 49. This position is untenable.
                             A
   As with the jurisdiction of military commissions, the
procedure of such commissions “has [not] been prescribed
by statute,” but “has been adapted in each instance to the
need that called it forth.” Madsen, 343 U. S., at 347–348.
Indeed, this Court has concluded that “[i]n the absence of
attempts by Congress to limit the President’s power, it
appears that, as Commander in Chief of the Army and
Navy of the United States, he may, in time of war, estab
lish and prescribe the jurisdiction and procedure of mili
tary commissions.” Id., at 348. This conclusion is consis
tent with this Court’s understanding that military
commissions are “our common-law war courts.” Id., at
                      Cite as: 548 U. S. ____ (2006)                      31

                          THOMAS, J., dissenting

346–347.15 As such, “[s]hould the conduct of those who
compose martial-law tribunals become [a] matter of judicial
determination subsequently before the civil courts, those
courts will give great weight to the opinions of the officers as
to what the customs of war in any case justify and render
necessary.” Birkhimer 534.
  The Court nevertheless concludes that at least one
provision of the UCMJ amounts to an attempt by Congress
to limit the President’s power. This conclusion is not only

——————
  15 Though    it does not constitute a basis for any holding of the Court,
the Court maintains that, as a “general rule,” “the procedures govern
ing trials by military commission historically have been the same as
those governing courts-martial.” Ante, at 54, 53. While it is undoubt
edly true that military commissions have invariably employed most of
the procedures employed by courts-martial, that is not a requirement.
See Winthrop 841 (“[M]ilitary commissions . . . are commonly conducted
according to the rules and forms governing courts-martial. These war-
courts are indeed more summary in their action than are the courts
held under the Articles of war, and . . . their proceedings . . . will not be
rendered illegal by the omission of details required upon trials by
courts-martial” (emphasis in original; footnotes omitted)); 1 U. N.
Commission 116–117 (“The [World War II] Mediterranean Regulations
(No. 8) provide that Military Commissions shall conduct their proceed
ings as may be deemed necessary for full and fair trial, having regard
for, but not being bound by, the rules of procedure prescribed for Gen
eral Courts Martial” (emphasis added)); id., at 117 (“In the [World War
II] European directive it is stated . . . that Military Commissions shall
have power to make, as occasion requires, such rules for the conduct of
their proceedings consistent with the powers of such Commissions, and
with the rules of procedure . . . as are deemed necessary for a full and
fair trial of the accused, having regard for, without being bound by, the
rules of procedure and evidence prescribed for General Courts Mar
tial”). Moreover, such a requirement would conflict with the settled
understanding of the flexible and responsive nature of military com
missions and the President’s wartime authority to employ such tribu
nals as he sees fit. See Birkhimer 537–538 (“[M]ilitary commissions may
so vary their procedure as to adapt it to any situation, and may extend
their powers to any necessary degree. . . . The military commander decides
upon the character of the military tribunal which is suited to the occasion
. . . and his decision is final”).
32                 HAMDAN v. RUMSFELD

                    THOMAS, J., dissenting

contrary to the text and structure of the UCMJ, but it is
also inconsistent with precedent of this Court. Consistent
with Madsen’s conclusion pertaining to the common-law
nature of military commissions and the President’s discre
tion to prescribe their procedures, Article 36 of the UCMJ
authorizes the President to establish procedures for mili
tary commissions “which shall, so far as he considers
practicable, apply the principles of law and the rules of
evidence generally recognized in the trial of criminal cases
in the United States district courts, but which may not be
contrary to or inconsistent with this chapter.” 10 U. S. C.
§836(a) (emphasis added). Far from constraining the
President’s authority, Article 36 recognizes the President’s
prerogative to depart from the procedures applicable in
criminal cases whenever he alone does not deem such
procedures “practicable.” While the procedural regula
tions promulgated by the Executive must not be “contrary
to” the UCMJ, only a few provisions of the UCMJ mention
“military commissions,” see ante, at 58, n. 49, and there is
no suggestion that the procedures to be employed by
Hamdan’s commission implicate any of those provisions.
   Notwithstanding the foregoing, the Court concludes that
Article 36(b) of the UCMJ, 10 U. S. C. §836(b), which
provides that “ ‘[a]ll rules and regulations made under this
article shall be uniform insofar as practicable,’ ” ante, at
57, requires the President to employ the same rules and
procedures in military commissions as are employed by
courts-martial “insofar as practicable.” Ante, at 59. The
Court further concludes that Hamdan’s commission is
unlawful because the President has not explained why it
is not practicable to apply the same rules and procedures
to Hamdan’s commission as would be applied in a trial by
court martial. Ante, at 60.
   This interpretation of §836(b) is unconvincing. As an
initial matter, the Court fails to account for our cases
interpreting the predecessor to Article 21 of the UCMJ—
                    Cite as: 548 U. S. ____ (2006)                 33

                        THOMAS, J., dissenting

Article 15 of the Articles of War—which provides crucial
context that bears directly on the proper interpretation of
Article 36(b). Article 15 of the Articles of War provided
that:
     “The provisions of these articles conferring jurisdic
     tion upon courts-martial shall not be construed as de
     priving military commissions, provost courts, or other
     military tribunals of concurrent jurisdiction in respect
     of offenders or offences that by statute or by the law of
     war may be triable by such military commissions,
     provost courts, or other military tribunals.”
In Yamashita, this Court concluded that Article 15 of the
Articles of War preserved the President’s unfettered au
thority to prescribe military commission procedure. The
Court explained, “[b]y thus recognizing military commis
sions in order to preserve their traditional jurisdiction
over enemy combatants unimpaired by the Articles, Con
gress gave sanction . . . to any use of the military commis
sion contemplated by the common law of war.” 327 U. S.,
at 20 (emphasis added)16; see also Quirin, 317 U. S., at 28;
Madsen, 343 U. S., at 355. In reaching this conclusion,
this Court treated as authoritative the congressional
testimony of Judge Advocate General Crowder, who testi
——————
  16 The Court suggests that Congress’ amendment to Article 2 of the
UCMJ, providing that the UCMJ applies to “persons within an area
leased by or otherwise reserved or acquired for the use of the United
States,” 10 U. S. C. §802(a)(12), deprives Yamashita’s conclusion
respecting the President’s authority to promulgate military commission
procedures of its “precedential value.” Ante, at 56. But this merely
begs the question of the scope and content of the remaining provisions
of the UCMJ. Nothing in the additions to Article 2, or any other
provision of the UCMJ, suggests that Congress has disturbed this
Court’s unequivocal interpretation of Article 21 as preserving the
common-law status of military commissions and the corresponding
authority of the President to set their procedures pursuant to his
commander-in-chief powers. See Quirin, 317 U. S., at 28; Yamashita,
327 U. S., at 20; Madsen v. Kinsella, 343 U. S. 341, 355 (1952).
34                 HAMDAN v. RUMSFELD

                    THOMAS, J., dissenting

fied that Article 15 of the Articles of War was enacted to
preserve the military commission as “ ‘our common-law
war court.’ ” Yamashita, supra, at 19, n. 7. And this Court
recognized that Article 15’s preservation of military com
missions as common-law war courts preserved the Presi
dent’s commander-in-chief authority to both “establish”
military commissions and to “prescribe [their] proce
dure[s].” Madsen, 343 U. S., at 348; id., at 348–349 (ex
plaining that Congress had “refrain[ed] from legislating”
in the area of military commission procedures, in “con
tras[t] with its traditional readiness to . . . prescrib[e],
with particularity, the jurisdiction and procedure of
United States courts-martial”); cf. Green 834 (“The mili
tary commission exercising jurisdiction under common law
authority is usually appointed by a superior military
commander and is limited in its procedure only by the will
of that commander. Like any other common law court, in
the absence of directive of superior authority to the con
trary, the military commission is free to formulate its own
rules of procedure”).
   Given these precedents, the Court’s conclusion that
Article 36(b) requires the President to apply the same
rules and procedures to military commissions as are appli
cable to courts-martial is unsustainable. When Congress
codified Article 15 of the Articles of War in Article 21 of
the UCMJ it was “presumed to be aware of . . . and to
adopt” this Court’s interpretation of that provision as
preserving the common-law status of military commis
sions, inclusive of the President’s unfettered authority to
prescribe their procedures. Lorillard v. Pons, 434 U. S.
575, 580 (1978). The Court’s conclusion that Article 36(b)
repudiates this settled meaning of Article 21 is not based
upon a specific textual reference to military commissions,
but rather on a one-sentence subsection providing that
“[a]ll rules and regulations made under this article shall
be uniform insofar as practicable.” 10 U. S. C. §836(b).
                  Cite as: 548 U. S. ____ (2006)            35

                     THOMAS, J., dissenting

This is little more than an impermissible repeal by impli
cation. See Branch v. Smith, 538 U. S. 254, 273 (2003).
(“We have repeatedly stated . . . that absent a clearly
expressed congressional intention, repeals by implication
are not favored” (citation and internal quotation marks
omitted)). Moreover, the Court’s conclusion is flatly con
trary to its duty not to set aside Hamdan’s commission
“without the clear conviction that [it is] in conflict with the
. . . laws of Congress constitutionally enacted.” Quirin,
supra, at 25 (emphasis added).
    Nothing in the text of Article 36(b) supports the Court’s
sweeping conclusion that it represents an unprecedented
congressional effort to change the nature of military com
missions from common-law war courts to tribunals that
must presumptively function like courts-martial. And
such an interpretation would be strange indeed. The
vision of uniformity that motivated the adoption of the
UCMJ, embodied specifically in Article 36(b), is nothing
more than uniformity across the separate branches of the
armed services. See ch. 169, 64 Stat. 107 (preamble to the
UCMJ explaining that the UCMJ is an act “[t]o unify,
consolidate, revise, and codify the Articles of War, the
Articles for the Government of the Navy, and the discipli
nary laws of the Coast Guard”). There is no indication
that the UCMJ was intended to require uniformity in
procedure between courts-martial and military commis
sions, tribunals that the UCMJ itself recognizes are differ
ent. To the contrary, the UCMJ expressly recognizes that
different tribunals will be constituted in different manners
and employ different procedures. See 10 U. S. C. §866
(providing for three different types of courts-martial—
general, special, and summary—constituted in different
manners and employing different procedures). Thus,
Article 36(b) is best understood as establishing that, so far
as practicable, the rules and regulations governing tribu
nals convened by the Navy must be uniform with the rules
36                     HAMDAN v. RUMSFELD

                         THOMAS, J., dissenting

and regulations governing tribunals convened by the
Army. But, consistent with this Court’s prior interpreta
tions of Article 21 and over a century of historical practice,
it cannot be understood to require the President to con
form the procedures employed by military commissions to
those employed by courts-martial.17
   Even if Article 36(b) could be construed to require pro
cedural uniformity among the various tribunals contem
plated by the UCMJ, Hamdan would not be entitled to
relief. Under the Court’s reading, the President is entitled
to prescribe different rules for military commissions than
for courts-martial when he determines that it is not “prac
ticable” to prescribe uniform rules. The Court does not
resolve the level of deference such determinations would
be owed, however, because, in its view, “[t]he President
has not . . . [determined] that it is impracticable to apply
the rules for courts-martial.” Ante, at 60. This is simply
not the case. On the same day that the President issued
Military Commission Order No. 1, the Secretary of De
fense explained that “the president decided to establish
——————
  17 Itbears noting that while the Court does not hesitate to cite legis
lative history that supports its view of certain statutory provisions, see
ante, at 14–15, and n. 10, it makes no citation of the legislative history
pertaining to Article 36(b), which contradicts its interpretation of that
provision. Indeed, if it were authoritative, the only legislative history
relating to Article 36(b) would confirm the obvious—Article 36(b)’s
uniformity requirement pertains to uniformity between the three
branches of the Armed Forces, and no more. When that subsection was
introduced as an amendment to Article 36, its author explained that it
would leave the three branches “enough leeway to provide a different
provision where it is absolutely necessary” because “there are some
differences in the services.” Hearings on H. R. 2498 before the Sub
committee No. 1 of the House Committee on Armed Services, 81st
Cong., 1st Sess., 1015 (1949). A further statement explained that
“there might be some slight differences that would pertain as to the
Navy in contrast to the Army, but at least [Article 36(b)] is an expres
sion of the congressional intent that we want it to be as uniform as
possible.” Ibid.
                 Cite as: 548 U. S. ____ (2006)           37

                    THOMAS, J., dissenting

military commissions because he wanted the option of a
process that is different from those processes which we
already have, namely the federal court system . . . and the
military court system,” Dept. of Defense News Briefing on
Military Commissions (Mar. 21, 2002) (remarks of Donald
Rumsfeld), available at http://www.dod.gov/transcrips/
2002/t03212002_t0321sd.html (as visited June 26, 2006,
and available in Clerk of Court’s case file) (hereinafter
News Briefing), and that “[t]he commissions are intended
to be different . . . because the [P]resident recognized that
there had to be differences to deal with the unusual situa
tion we face and that a different approach was needed.”
Ibid. The President reached this conclusion because
    “we’re in the middle of a war, and . . . had to design a
    procedure that would allow us to pursue justice for
    these individuals while at the same time prosecuting
    the war most effectively. And that means setting
    rules that would allow us to preserve our intelligence
    secrets, develop more information about terrorist ac
    tivities that might be planned for the future so that
    we can take action to prevent terrorist attacks against
    the United States. . . . [T]here was a constant balanc
    ing of the requirements of our war policy and the im
    portance of providing justice for individuals . . . and
    each deviation from the standard kinds of rules that
    we have in our criminal courts was motivated by the
    desire to strike the balance between individual justice
    and the broader war policy.” Ibid. (remarks of Doug
    las J. Feith, Under Secretary of Defense for Policy
    (emphasis added)).
The Court provides no explanation why the President’s
determination that employing court-martial procedures in
the military commissions established pursuant to Military
Commission Order No. 1 would hamper our war effort is in
any way inadequate to satisfy its newly minted “practica
38                    HAMDAN v. RUMSFELD

                        THOMAS, J., dissenting

bility” requirement. On the contrary, this determination
is precisely the kind for which the “Judiciary has neither
aptitude, facilities nor responsibility and which has long
been held to belong in the domain of political power not
subject to judicial intrusion or inquiry.’ ” Chicago &
Southern Air Lines, Inc. v. Waterman S. S. Corp., 333 U. S.
103, 111 (1948). And, in the context of the present conflict, it
is exactly the kind of determination Congress countenanced
when it authorized the President to use all necessary and
appropriate force against our enemies. Accordingly, the
President’s determination is sufficient to satisfy any practi
cability requirement imposed by Article 36(b).
   The plurality further contends that Hamdan’s commis
sion is unlawful because it fails to provide him the right to
be present at his trial, as recognized in 10 U. S. C. A.
§839(c) (Supp. 2006). Ante, at 61. But §839(c) applies to
courts-martial, not military commissions. It provides:
       “When the members of a court-martial deliberate or
     vote, only the members may be present. All other
     proceedings, including any other consultation of the
     members of the court with counsel or the military
     judge, shall be made a part of the record and shall be
     in the presence of the accused, the defense counsel,
     the trial counsel, and, in cases in which a military
     judge has been detailed to the court, the military
     judge.”
In context, “all other proceedings” plainly refers exclusively
to “other proceedings” pertaining to a court-martial.18 This
is confirmed by the provision’s subsequent reference to
“members of the court” and to “cases in which a military
——————
  18 In addition to being foreclosed by the text of the provision, the

Court’s suggestion that 10 U. S. C. A. §839(c) (Supp. 2006) applies to
military commissions is untenable because it would require, in military
commission proceedings, that the accused be present when the mem
bers of the commission voted on his guilt or innocence.
                 Cite as: 548 U. S. ____ (2006)           39

                    THOMAS, J., dissenting

judge has been detailed to the court.” It is also confirmed
by the other provisions of §839, which refer only to courts-
martial. See §§839(a)(1)–(4) (“[A]ny time after the service
of charges which have been referred for trial to a court-
martial composed of a military judge and members, the
military judge may . . . call the court into session without
the presence of the members for the purpose of,” hearing
motions, issuing rulings, holding arraignments, receiving
pleas, and performing various procedural functions). See
also §839(b) (“Proceedings under subsection (a) shall be
conducted in the presence of the accused”). Section 839(c)
simply does not address the procedural requirements of
military commissions.
                              B
   The Court contends that Hamdan’s military commission
is also unlawful because it violates Common Article 3 of the
Geneva Conventions, see ante, at 65–72. Furthermore,
Hamdan contends that his commission is unlawful because
it violates various provisions of the Third Geneva Conven
tion. These contentions are untenable.
                               1
   As an initial matter, and as the Court of Appeals con
cluded, both of Hamdan’s Geneva Convention claims are
foreclosed by Johnson v. Eisentrager, 339 U. S. 763 (1950).
In that case the respondents claimed, inter alia, that their
military commission lacked jurisdiction because it failed to
provide them with certain procedural safeguards that they
argued were required under the Geneva Conventions. Id.,
at 789–790. While this Court rejected the underlying mer
its of the respondents’ Geneva Convention claims, id., at
790, it also held, in the alternative, that the respondents
could “not assert . . . that anything in the Geneva Conven
tion makes them immune from prosecution or punishment
for war crimes,” id., at 789. The Court explained:
40                 HAMDAN v. RUMSFELD

                    THOMAS, J., dissenting

        “We are not holding that these prisoners have no
     right which the military authorities are bound to re
     spect. The United States, by the Geneva Convention
     of July 27, 1929, 47 Stat. 2021, concluded with forty-
     six other countries, including the German Reich, an
     agreement upon the treatment to be accorded cap
     tives. These prisoners claim to be and are entitled to
     its protection. It is, however, the obvious scheme of
     the Agreement that responsibility for observance and
     enforcement of these rights is upon political and mili
     tary authorities. Rights of alien enemies are vindi
     cated under it only through protests and intervention
     of protecting powers as the rights of our citizens
     against foreign governments are vindicated only by
     Presidential intervention.” Id., at 789, n. 14.
This alternative holding is no less binding than if it were
the exclusive basis for the Court’s decision. See Massa
chusetts v. United States, 333 U. S. 611, 623 (1948). While
the Court attempts to cast Eisentrager’s unqualified,
alternative holding as footnote dictum, ante, at 63–64, it
does not dispute the correctness of its conclusion, namely,
that the provisions of the 1929 Geneva Convention were
not judicially enforceable because that Convention con
templated that diplomatic measures by political and mili
tary authorities were the exclusive mechanisms for such
enforcement. Nor does the Court suggest that the 1949
Geneva Conventions departed from this framework. See
ante, at 64 (“We may assume that ‘the obvious scheme’ of
the 1949 Conventions is identical in all relevant respects
to that of the 1929 Convention”).
  Instead, the Court concludes that petitioner may seek
judicial enforcement of the provisions of the Geneva Con
ventions because “they are . . . part of the law of war. And
compliance with the law of war is the condition upon
which the authority set forth in Article 21 is granted.”
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                    THOMAS, J., dissenting

Ante, at 65 (citation omitted). But Article 21 authorizes
the use of military commissions; it does not purport to
render judicially enforceable aspects of the law of war that
are not so enforceable of their own accord. See Quirin, 317
U. S., at 28 (by enacting Article 21, “Congress has explic
itly provided, so far as it may constitutionally do so, that
military tribunals shall have jurisdiction to try offenders
or offenses against the law of war”). The Court cannot
escape Eisentrager’s holding merely by observing that
Article 21 mentions the law of war; indeed, though Eisen
trager did not specifically consider the Court’s novel inter
pretation of Article 21, Eisentrager involved a challenge to
the legality of a World War II military commission, which,
like all such commissions, found its authorization in Arti
cle 15 of the Articles of War, the predecessor to Article 21
of the UCMJ. Thus, the Court’s interpretation of Article
21 is foreclosed by Eisentrager.
   In any event, the Court’s argument is too clever by half.
The judicial nonenforceability of the Geneva Conventions
derives from the fact that those Conventions have exclu
sive enforcement mechanisms, see Eisentrager, supra, at
789, n. 14, and this, too, is part of the law of war. The
Court’s position thus rests on the assumption that Article
21’s reference to the “laws of war” selectively incorporates
only those aspects of the Geneva Conventions that the
Court finds convenient, namely, the substantive require
ments of Common Article 3, and not those aspects of the
Conventions that the Court, for whatever reason, disfavors,
namely the Conventions’ exclusive diplomatic enforcement
scheme. The Court provides no account of why the partial
incorporation of the Geneva Conventions should extend
only so far—and no further—because none is available
beyond its evident preference to adjudicate those matters
that the law of war, through the Geneva Conventions,
consigns exclusively to the political branches.
   Even if the Court were correct that Article 21 of the
42                 HAMDAN v. RUMSFELD

                    THOMAS, J., dissenting

UCMJ renders judicially enforceable aspects of the law of
war that are not so enforceable by their own terms, Article
21 simply cannot be interpreted to render judicially en
forceable the particular provision of the law of war at issue
here, namely Common Article 3 of the Geneva Conven
tions. As relevant, Article 21 provides that “[t]he provi
sions of this chapter conferring jurisdiction upon courts-
martial do not deprive military commissions . . . of concur
rent jurisdiction with respect to offenders or offenses that
by statute or by the law of war may be tried by military
commissions.” 10 U. S. C. §821 (emphasis added). Thus,
to the extent Article 21 can be interpreted as authorizing
judicial enforcement of aspects of the law of war that are
not otherwise judicially enforceable, that authorization
only extends to provisions of the law of war that relate to
whether a particular “offender” or a particular “offense” is
triable by military commission. Common Article 3 of the
Geneva Conventions, the sole provision of the Geneva
Conventions relevant to the Court’s holding, relates to
neither. Rather, it relates exclusively to the particulars of
the tribunal itself, namely, whether it is “regularly consti
tuted” and whether it “afford[s] all the judicial guarantees
which are recognized as indispensable by civilized peo
ples.” Third Geneva Convention, Art. 3, ¶1(d), Relative to
the Treatment of Prisoners of War, Aug. 12, 1949, [1955] 6
U. S. T. 3316, 3320, T. I. A. S No. 3364.
                               2
   In addition to being foreclosed by Eisentrager, Hamdan’s
claim under Common Article 3 of the Geneva Conventions
is meritless. Common Article 3 applies to “armed conflict
not of an international character occurring in the territory
of one of the High Contracting Parties.” 6 U. S. T., at
3318. “Pursuant to [his] authority as Commander in Chief
and Chief Executive of the United States,” the President
has “accept[ed] the legal conclusion of the Department of
                  Cite as: 548 U. S. ____ (2006)            43

                     THOMAS, J., dissenting

Justice . . . that common Article 3 of Geneva does not
apply to . . . al Qaeda . . . detainees, because, among other
reasons, the relevant conflicts are international in scope
and common Article 3 applies only to ‘armed conflict not of
an international character.’ ” App. 35. Under this Court’s
precedents, “the meaning attributed to treaty provisions
by the Government agencies charged with their negotia
tion and enforcement is entitled to great weight.” Sumi
tomo Shoji America, Inc. v. Avagliano, 457 U. S. 176, 184–
185 (1982); United States v. Stuart, 489 U. S. 353, 369
(1989). Our duty to defer to the President’s understanding
of the provision at issue here is only heightened by the fact
that he is acting pursuant to his constitutional authority as
Commander in Chief and by the fact that the subject matter
of Common Article 3 calls for a judgment about the nature
and character of an armed conflict. See generally United
States v. Curtiss-Wright Export Corp., 299 U. S. 304, 320
(1936).
    The President’s interpretation of Common Article 3 is
reasonable and should be sustained. The conflict with al
Qaeda is international in character in the sense that it is
occurring in various nations around the globe. Thus, it is
also “occurring in the territory of” more than “one of the
High Contracting Parties.” The Court does not dispute the
President’s judgments respecting the nature of our conflict
with al Qaeda, nor does it suggest that the President’s
interpretation of Common Article 3 is implausible or
foreclosed by the text of the treaty. Indeed, the Court
concedes that Common Article 3 is principally concerned
with “furnish[ing] minimal protection to rebels involved in
. . . a civil war,” ante, at 68, precisely the type of conflict
the President’s interpretation envisions to be subject to
Common Article 3. Instead, the Court, without acknowl
edging its duty to defer to the President, adopts its own,
admittedly plausible, reading of Common Article 3. But
where, as here, an ambiguous treaty provision (“not of an
44                     HAMDAN v. RUMSFELD

                         THOMAS, J., dissenting

international character”) is susceptible of two plausible,
and reasonable, interpretations, our precedents require us
to defer to the Executive’s interpretation.
                                3
   But even if Common Article 3 were judicially enforce
able and applicable to the present conflict, petitioner
would not be entitled to relief. As an initial matter, any
claim petitioner has under Common Article 3 is not ripe.
The only relevant “acts” that “are and shall remain prohib
ited” under Common Article 3 are “the passing of sen
tences and the carrying out of executions without previous
judgment pronounced by a regularly constituted court
affording all the judicial guarantees which are recognized
as indispensable by civilized peoples.” Art. 3, ¶1(d), 6
U. S. T., at 1318, 1320 (emphases added). As its terms
make clear, Common Article 3 is only violated, as relevant
here, by the act of “passing of sentenc[e],” and thus Ham
dan will only have a claim if his military commission
convicts him and imposes a sentence. Accordingly, as
Hamdan’s claim is “contingent [upon] future events that
may not occur as anticipated, or indeed may not occur at
all,” it is not ripe for adjudication. Texas v. United States,
523 U. S. 296, 300 (1998) (internal quotation marks omit
ted).19 Indeed, even if we assume he will be convicted and
sentenced, whether his trial will be conducted in a manner
——————
  19 The Court does not dispute the conclusion that Common Article 3
cannot be violated unless and until Hamdan is convicted and sen
tenced. Instead, it contends that “the Geneva Conventions d[o] not
direct an accused to wait until sentence is imposed to challenge the
legality of the tribunal that is to try him.” Ante, at 62, n. 55. But the
Geneva Contentions do not direct defendants to enforce their rights
through litigation, but through the Conventions’ exclusive diplomatic
enforcement provisions. Moreover, neither the Court’s observation
respecting the Geneva Conventions nor its reference to the equitable
doctrine of abstention bears on the constitutional prohibition on adjudi
cating unripe claims.
                 Cite as: 548 U. S. ____ (2006)          45

                    THOMAS, J., dissenting

so as to deprive him of “the judicial guarantees which are
recognized as indispensable by civilized peoples” is en
tirely speculative. And premature adjudication of Ham
dan’s claim is especially inappropriate here because
“reaching the merits of the dispute would force us to de
cide whether an action taken by one of the other two
branches of the Federal Government was unconstitu
tional.” Raines v. Byrd, 521 U. S. 811, 819–820 (1997).
   In any event, Hamdan’s military commission complies
with the requirements of Common Article 3. It is plainly
“regularly constituted” because such commissions have
been employed throughout our history to try unlawful
combatants for crimes against the law of war. This Court
has recounted that history as follows:
    “ ‘By a practice dating from 1847 and renewed and
    firmly established during the Civil War, military
    commissions have become adopted as authorized tri
    bunals in this country in time of war. . . . Their com
    petency has been recognized not only in acts of Con
    gress, but in executive proclamations, in rulings of the
    courts, and in the opinions of the Attorneys General.’ ”
    Madsen, 343 U. S., at 346, n. 8.
Hamdan’s commission has been constituted in accordance
with these historical precedents. As I have previously
explained, the procedures to be employed by that commis
sion, and the Executive’s authority to alter those proce
dures, are consistent with the practice of previous Ameri
can military commissions. See supra, at 30–34 , and n. 15.
   The Court concludes Hamdan’s commission fails to
satisfy the requirements of Common Article 3 not because
it differs from the practice of previous military commis
sions but because it “deviate[s] from [the procedures]
governing courts-martial.” Ante, at 71. But there is nei
ther a statutory nor historical requirement that military
commissions conform to the structure and practice of
46                  HAMDAN v. RUMSFELD

                     THOMAS, J., dissenting

courts-martial. A military commission is a different tri
bunal, serving a different function, and thus operates
pursuant to different procedures. The 150-year pedigree
of the military commission is itself sufficient to establish
that such tribunals are “regularly constituted court[s].”
Art. 3, ¶1(d), 6 U. S. T., at 3320.
  Similarly, the procedures to be employed by Hamdan’s
commission afford “all the judicial guarantees which are
recognized as indispensable by civilized peoples.” Neither
the Court nor petitioner disputes the Government’s de
scription of those procedures.
     “Petitioner is entitled to appointed military legal coun
     sel, 32 C.F.R. 9.4(c)(2), and may retain a civilian attor
     ney (which he has done), 32 C.F.R. 9.4(c)(2)(iii)(B). Pe
     titioner is entitled to the presumption of innocence, 32
     C.F.R. 9.5(b), proof beyond a reasonable doubt, 32
     C.F.R. 9.5(c), and the right to remain silent, 32 C.F.R.
     9.5(f). He may confront witnesses against him, 32
     C.F.R. 9.5(i), and may subpoena his own witnesses, if
     reasonably available, 32 C.F.R. 9.5(h). Petitioner may
     personally be present at every stage of the trial unless
     he engages in disruptive conduct or the prosecution
     introduces classified or otherwise protected informa
     tion for which no adequate substitute is available and
     whose admission will not deprive him of a full and fair
     trial, 32 C.F.R. 9.5(k); Military Commission Order No.
     1 (Dep’t of Defense Aug. 31, 2005) §6(B)(3) and
     (D)(5)(b). If petitioner is found guilty, the judgment
     will be reviewed by a review panel, the Secretary of
     Defense, and the President, if he does not designate
     the Secretary as the final decisionmaker. 32 C.F.R.
     9.6(h). The final judgment is subject to review in the
     Court of Appeals for the District of Columbia Circuit
     and ultimately in this Court. See DTA §1005(e)(3),
     119 Stat. 2743; 28 U. S. C. 1254(1).” Brief for Re
                    Cite as: 548 U. S. ____ (2006)                  47

                        THOMAS, J., dissenting

     spondents 4.
Notwithstanding these provisions, which in my judgment
easily satisfy the nebulous standards of Common Article
3,20 the plurality concludes that Hamdan’s commission is
unlawful because of the possibility that Hamdan will be
barred from proceedings and denied access to evidence
that may be used to convict him. Ante, at 70–72. But,
under the commissions’ rules, the Government may not
impose such bar or denial on Hamdan if it would render
his trial unfair, a question that is clearly within the scope
of the appellate review contemplated by regulation and
statute.
    Moreover, while the Executive is surely not required to
offer a particularized defense of these procedures prior to
their application, the procedures themselves make clear
that Hamdan would only be excluded (other than for
disruption) if it were necessary to protect classified (or
classifiable) intelligence, Dept. of Defense, Military Com
mission Order No. 1, §6(B)(3) (Aug. 31, 2005), including
the sources and methods for gathering such intelligence.
The Government has explained that “we want to make
sure that these proceedings, which are going on in the
middle of the war, do not interfere with our war effort and
. . . because of the way we would be able to handle interro
gations and intelligence information, may actually assist
us in promoting our war aims.” News Briefing (remarks of
Douglas J. Feith, Under Secretary of Defense for Policy).
And this Court has concluded, in the very context of a
——————
  20 Notably, a prosecutor before the Quirin military commission has
described these procedures as “a substantial improvement over those in
effect during World War II,” further observing that “[t]hey go a long
way toward assuring that the trials will be full and fair.” National
Institute of Military Justice, Procedures for Trials by Military Commis
sions of Certain Non-United States Citizens in the War Against Terror
ism, p. x (2002) (hereinafter Procedures for Trials) (foreword by Lloyd
N. Cutler).
48                  HAMDAN v. RUMSFELD

                     THOMAS, J., dissenting

threat to reveal our Nation’s intelligence gathering sources
and methods, that “[i]t is ‘obvious and unarguable’ that no
governmental interest is more compelling than the security
of the Nation,” Haig, 453 U. S., at 307 (quoting Aptheker v.
Secretary of State, 378 U. S. 500, 509 (1964)), and that
“[m]easures to protect the secrecy of our Government’s
foreign intelligence operations plainly serve these interests,”
Haig, supra, at 307. See also Snepp v. United States, 444
U. S. 507, 509, n. 3 (1980) (per curiam) (“The Government
has a compelling interest in protecting both the secrecy of
information important to our national security and the
appearance of confidentiality so essential to the effective
operation of our foreign intelligence service”); Curtiss-
Wright, 299 U. S., at 320. This interest is surely compelling
here. According to the Government, “[b]ecause al Qaeda
operates as a clandestine force relying on sleeper agents to
mount surprise attacks, one of the most critical fronts in the
current war involves gathering intelligence about future
terrorist attacks and how the terrorist network operates—
identifying where its operatives are, how it plans attacks,
who directs operations, and how they communicate.” Brief
for United States in No. 03–4792, United States v. Mous
saoui (CA4), p. 9. We should not rule out the possibility that
this compelling interest can be protected, while at the same
time affording Hamdan (and others like him) a fair trial.
   In these circumstances, “civilized peoples” would take
into account the context of military commission trials
against unlawful combatants in the war on terrorism,
including the need to keep certain information secret in
the interest of preventing future attacks on our Nation
and its foreign installations so long as it did not deprive
the accused of a fair trial. Accordingly, the President’s
understanding of the requirements of Common Article 3 is
entitled to “great weight.” See supra, at 43.
                 Cite as: 548 U. S. ____ (2006)          49

                    THOMAS, J., dissenting

                              4
   In addition to Common Article 3, which applies to con
flicts “not of an international character,” Hamdan also
claims that he is entitled to the protections of the Third
Geneva Convention, which applies to conflicts between
two or more High Contracting Parties. There is no merit
to Hamdan’s claim.
   Article 2 of the Convention provides that “the present
Convention shall apply to all cases of declared war or of
any other armed conflict which may arise between two or
more of the High Contracting Parties.” 6 U. S. T., at 1318.
“Pursuant to [his] authority as Commander in Chief and
Chief Executive of the United States,” the President has
determined that the Convention is inapplicable here,
explaining that “none of the provisions of Geneva apply to
our conflict with al Qaeda in Afghanistan or elsewhere
throughout the world, because, among other reasons, al
Qaeda is not a High Contracting Party.” App. 35. The
President’s findings about the nature of the present con
flict with respect to members of al Qaeda operating in
Afghanistan represents a core exercise of his commander-
in-chief authority that this Court is bound to respect. See
Prize Cases, 2 Black, at 670.
                      *    *     *
  For these reasons, I would affirm the judgment of the
Court of Appeals.
                 Cite as: 548 U. S. ____ (2006)            1

                     ALITO, J., dissenting

SUPREME COURT OF THE UNITED STATES
                         _________________

                          No. 05–184
                         _________________


 SALIM AHMED HAMDAN, PETITIONER v. DONALD
  H. RUMSFELD, SECRETARY OF DEFENSE, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

    APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT

                        [June 29, 2006] 


   JUSTICE ALITO, with whom JUSTICE SCALIA and JUSTICE
THOMAS join in Parts I–III, dissenting.
   For the reasons set out in JUSTICE SCALIA’s dissent,
which I join, I would hold that we lack jurisdiction. On
the merits, I join JUSTICE THOMAS’ dissent with the excep
tion of Parts I, II–C–1, and III–B–2, which concern mat
ters that I find unnecessary to reach. I add the following
comments to provide a further explanation of my reasons
for disagreeing with the holding of the Court.
                              I
   The holding of the Court, as I understand it, rests on the
following reasoning. A military commission is lawful only
if it is authorized by 10 U. S. C. §821; this provision per
mits the use of a commission to try “offenders or offenses”
that “by statute or by the law of war may be tried by” such
a commission; because no statute provides that an of
fender such as petitioner or an offense such as the one
with which he is charged may be tried by a military com
mission, he may be tried by military commission only if
the trial is authorized by “the law of war”; the Geneva
Conventions are part of the law of war; and Common
Article 3 of the Conventions prohibits petitioner’s trial
because the commission before which he would be tried is
not “a regularly constituted court,” Third Geneva Conven
2                  HAMDAN v. RUMSFELD

                      ALITO, J., dissenting

tion, Art. 3, ¶1(d), Relative to the Treatment of Prisoners
of War, Aug. 12, 1949, [1955] 6 U. S. T. 3316, 3320,
T. I. A. S. No. 3364. I disagree with this holding because
petitioner’s commission is “a regularly constituted court.”
   Common Article 3 provides as follows:
    “In the case of armed conflict not of an international
    character occurring in the territory of one of the High
    Contracting Parties, each Party to the conflict shall
    be bound to apply, as a minimum, the following
    provisions:
      “(1) . . . [T]he following acts are and shall remain
    prohibited . . . :
      “(d) [T]he passing of sentences and the carrying out
    of executions without previous judgment pronounced
    by a regularly constituted court affording all the judi
    cial guarantees which are recognized as indispensable
    by civilized peoples.” Id., at 3318–3320 (emphasis
    added).
  Common Article 3 thus imposes three requirements.
Sentences may be imposed only by (1) a “court” (2) that is
“regularly constituted” and (3) that affords “all the judicial
guarantees which are recognized as indispensable by
civilized peoples.” Id., at 3320.
  I see no need here to comment extensively on the mean
ing of the first and third requirements. The first require
ment is largely self-explanatory, and, with respect to the
third, I note only that on its face it imposes a uniform
international standard that does not vary from signatory
to signatory.
  The second element (“regularly constituted”) is the one
on which the Court relies, and I interpret this element to
require that the court be appointed or established in ac
cordance with the appointing country’s domestic law. I
agree with the Court, see ante, at 69, n. 64, that, as used
in Common Article 3, the term “regularly” is synonymous
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                      ALITO, J., dissenting

with “properly.” The term “constitute” means “appoint,”
“set up,” or “establish,” Webster’s Third New International
Dictionary 486 (1961), and therefore “regularly consti
tuted” means properly appointed, set up, or established.
Our cases repeatedly use the phrases “regularly consti
tuted” and “properly constituted” in this sense. See, e.g.,
Hamdi v. Rumsfeld, 542 U. S. 507, 538 (2004) (plurality
opinion of O’Connor, J.); Nguyen v. United States, 539 U. S.
69, 83 (2003); Ryder v. United States, 515 U. S. 177, 187
(1995); Williams v. Bruffy, 96 U. S. 176, 185 (1878).
   In order to determine whether a court has been properly
appointed, set up, or established, it is necessary to refer to
a body of law that governs such matters. I interpret
Common Article 3 as looking to the domestic law of the
appointing country because I am not aware of any interna
tional law standard regarding the way in which such a
court must be appointed, set up, or established, and be
cause different countries with different government struc
tures handle this matter differently. Accordingly, “a
regularly constituted court” is a court that has been ap
pointed, set up, or established in accordance with the
domestic law of the appointing country.
                             II
  In contrast to this interpretation, the opinions support
ing the judgment today hold that the military commission
before which petitioner would be tried is not “a regularly
constituted court” (a) because “no evident practical need
explains” why its “structure and composition . . . deviate
from conventional court-martial standards,” ante, at 11
(KENNEDY, J., concurring in part); see also ante, at 69–70
(Opinion of the Court); and (b) because, contrary to 10
U. S. C. §836(b), the procedures specified for use in the
proceeding before the military commission impermissibly
differ from those provided under the Uniform Code of
Military Justice (UCMJ) for use by courts-martial, ante, at
4                  HAMDAN v. RUMSFELD

                     ALITO, J., dissenting

52–62 (Opinion of the Court); ante, at 16–18 (KENNEDY, J.,
concurring in part). I do not believe that either of these
grounds is sound.
                               A
   I see no basis for the Court’s holding that a military
commission cannot be regarded as “a regularly constituted
court” unless it is similar in structure and composition to a
regular military court or unless there is an “evident prac
tical need” for the divergence. There is no reason why a
court that differs in structure or composition from an
ordinary military court must be viewed as having been
improperly constituted. Tribunals that vary significantly
in structure, composition, and procedures may all be
“regularly” or “properly” constituted. Consider, for exam
ple, a municipal court, a state trial court of general juris
diction, an Article I federal trial court, a federal district
court, and an international court, such as the Interna
tional Criminal Tribunal for the Former Yugoslavia.
Although these courts are “differently constituted” and
differ substantially in many other respects, they are all
“regularly constituted.”
   If Common Article 3 had been meant to require trial
before a country’s military courts or courts that are simi
lar in structure and composition, the drafters almost
certainly would have used language that expresses that
thought more directly. Other provisions of the Convention
Relative to the Treatment of Prisoners of War refer ex
pressly to the ordinary military courts and expressly
prescribe the “uniformity principle” that JUSTICE
KENNEDY sees in Common Article 3, see ante, at 8–9.
Article 84 provides that “[a] prisoner of war shall be tried
only by a military court, unless the existing laws of the
Detaining Power expressly permit the civil courts to try a
member of the armed forces of the Detaining Power in
respect of the particular offence alleged to have been
                 Cite as: 548 U. S. ____ (2006)            5

                     ALITO, J., dissenting

committed by the prisoner of war.” 6 U. S. T., at 3382.
Article 87 states that “[p]risoners of war may not be sen
tenced by the military authorities and courts of the De
taining Power to any penalties except those provided for in
respect of members of the armed forces of the said Power
who have committed the same acts.” Id., at 3384. Simi
larly, Article 66 of the Geneva Convention Relative to the
Treatment of Civilian Persons in Time of War—a provi
sion to which the Court looks for guidance in interpreting
Common Article 3, see ante at 69—expressly provides that
civilians charged with committing crimes in occupied
territory may be handed over by the occupying power “to
its properly constituted, non-political military courts, on
condition that the said courts sit in the occupied country.”
6 U. S. T. 3516, 3558–3560, T. I. A. S. No. 3365. If Com
mon Article 3 had been meant to incorporate a “uniformity
principle,” it presumably would have used language like
that employed in the provisions noted above. For these
reasons, I cannot agree with the Court’s conclusion that
the military commission at issue here is not a “regularly
constituted court” because its structure and composition
differ from those of a court-martial.
   Contrary to the suggestion of the Court, see ante, at 69,
the commentary on Article 66 of Fourth Geneva Conven
tion does not undermine this conclusion. As noted, Article
66 permits an occupying power to try civilians in its “prop
erly constituted, non-political military courts,” 6 U. S. T.,
at 3558. The commentary on this provision states:
    “The courts are to be ‘regularly constituted’. This
    wording definitely excludes all special tribunals. It is
    the ordinary military courts of the Occupying Power
    which will be competent.” 4 Int’l Comm. of Red Cross,
    Commentary: Geneva Convention Relative to the Pro
    tection of Civilian Persons in Time of War 340 (1958)
    (hereinafter GCIV Commentary).
6                  HAMDAN v. RUMSFELD

                     ALITO, J., dissenting

   The Court states that this commentary “defines ‘ “regu
larly constituted” ’ tribunals to include ‘ordinary military
courts’ and ‘definitely exclud[e] all special tribunals.’ ”
Ante, at 69 (alteration in original). This much is clear
from the commentary itself. Yet the mere statement that
a military court is a regularly constituted tribunal is of no
help in addressing petitioner’s claim that his commission
is not such a tribunal. As for the commentary’s mention of
“special tribunals,” it is doubtful whether we should take
this gloss on Article 66—which forbids an occupying power
from trying civilians in courts set up specially for that
purpose—to tell us much about the very different context
addressed by Common Article 3.
   But even if Common Article 3 recognizes this prohibi
tion on “special tribunals,” that prohibition does not cover
petitioner’s tribunal. If “special” means anything in con
tradistinction to “regular,” it would be in the sense of
“special” as “relating to a single thing,” and “regular” as
“uniform in course, practice, or occurrence.” Webster’s
Third New International Dictionary 2186, 1913. Insofar
as respondents propose to conduct the tribunals according
to the procedures of Military Commission Order No. 1 and
orders promulgated thereunder—and nobody has sug
gested respondents intend otherwise—then it seems that
petitioner’s tribunal, like the hundreds of others respon
dents propose to conduct, is very much regular and not at
all special.
                            B
   I also disagree with the Court’s conclusion that peti
tioner’s military commission is “illegal,” ante, at 62, be
cause its procedures allegedly do not comply with 10
U. S. C. §836. Even if §836(b), unlike Common Article 3,
does impose at least a limited uniformity requirement
amongst the tribunals contemplated by the UCMJ, but see
ante, at 35 (THOMAS, J., dissenting), and even if it is as
                  Cite as: 548 U. S. ____ (2006)            7

                      ALITO, J., dissenting

sumed for the sake of argument that some of the proce
dures specified in Military Commission Order No. 1
impermissibly deviate from court-martial procedures, it
does not follow that the military commissions created by
that order are not “regularly constituted” or that trying
petitioner before such a commission would be inconsistent
with the law of war. If Congress enacted a statute requir
ing the federal district courts to follow a procedure that is
unconstitutional, the statute would be invalid, but the
district courts would not. Likewise, if some of the proce
dures that may be used in military commission proceed
ings are improper, the appropriate remedy is to proscribe
the use of those particular procedures, not to outlaw the
commissions. I see no justification for striking down the
entire commission structure simply because it is possible
that petitioner’s trial might involve the use of some proce
dure that is improper.
                               III
  Returning to the three elements of Common Article 3—
(1) a court, (2) that is appointed, set up, and established in
compliance with domestic law, and (3) that respects uni
versally recognized fundamental rights—I conclude that
all of these elements are satisfied in this case.
                            A
  First, the commissions qualify as courts.
  Second, the commissions were appointed, set up, and
established pursuant to an order of the President, just like
the commission in Ex parte Quirin, 317 U. S. 1 (1942), and
the Court acknowledges that Quirin recognized that the
statutory predecessor of 10 U. S. C. §821 “preserved” the
President’s power “to convene military commissions,” ante,
at 29. Although JUSTICE KENNEDY concludes that “an
acceptable degree of independence from the Executive is
necessary to render a commission ‘regularly constituted’
8                      HAMDAN v. RUMSFELD

                          ALITO, J., dissenting

by the standards of our Nation’s system of justice,” ante at
9–10, he offers no support for this proposition (which in
any event seems to be more about fairness or integrity
than regularity). The commission in Quirin was certainly
no more independent from the Executive than the com
missions at issue here, and 10 U. S. C. §§821 and 836 do
not speak to this issue.1
   Finally, the commission procedures, taken as a whole,
and including the availability of review by a United States
Court of Appeals and by this Court, do not provide a basis
for deeming the commissions to be illegitimate. The Court
questions the following two procedural rules: the rule
allowing the Secretary of Defense to change the governing
rules “ ‘from time to time’ ” (which does not rule out mid-
trial changes), see ante, at 70, n. 65 (Opinion of the Court);
ante, at 9–10 (KENNEDY, J., concurring in part), and the
rule that permits the admission of any evidence that
would have “ ‘probative value to a reasonable person’ ”
(which departs from our legal system’s usual rules of
evidence), see ante, at 51, 60 (Opinion of the Court); ante,
at 16–18 (KENNEDY, J., concurring in part).2 Neither
of these two rules undermines the legitimacy of the
commissions.
   Surely the entire commission structure cannot be
stricken merely because it is possible that the governing
rules might be changed during the course of one or more
——————
    1 Section821 looks to the “law of war,” not separation of powers is
sues. And §836, as JUSTICE KENNEDY notes, concerns procedures, not
structure, see ante, at 10.
  2 The plurality, but not JUSTICE KENNEDY, suggests that the commis

sion rules are improper insofar as they allow a defendant to be denied
access to evidence under some circumstances. See, ante, at 70–72. But
here too, if this procedure is used in a particular case and the accused is
convicted, the validity of this procedure can be challenged in the review
proceeding in that case. In that context, both the asserted need for the
procedure and its impact on the accused can be analyzed in concrete
terms.
                 Cite as: 548 U. S. ____ (2006)           9

                     ALITO, J., dissenting

proceedings. If a change is made and applied during the
course of an ongoing proceeding and if the accused is
found guilty, the validity of that procedure can be consid
ered in the review proceeding for that case. After all, not
every midtrial change will be prejudicial. A midtrial
change might amend the governing rules in a way that is
inconsequential or actually favorable to the accused.
  As for the standard for the admission of evidence at
commission proceedings, the Court does not suggest that
this rule violates the international standard incorporated
into Common Article 3 (“the judicial guarantees which are
recognized as indispensable by civilized peoples,” 6
U. S. T., at 3320). Rules of evidence differ from country to
country, and much of the world does not follow aspects of
our evidence rules, such as the general prohibition against
the admission of hearsay. See, e.g., Blumenthal, Shedding
Some Light on Calls for Hearsay Reform: Civil Law Hear
say Rules in Historical and Modern Perspective, 13 Pace
Int’l L. Rev. 93, 96–101 (2001). If a particular accused
claims to have been unfairly prejudiced by the admission
of particular evidence, that claim can be reviewed in the
review proceeding for that case. It makes no sense to
strike down the entire commission structure based on
speculation that some evidence might be improperly ad
mitted in some future case.
  In sum, I believe that Common Article 3 is satisfied here
because the military commissions (1) qualify as courts, (2)
that were appointed and established in accordance with
domestic law, and (3) any procedural improprieties that
might occur in particular cases can be reviewed in those
cases.
                               B
  The commentary on Common Article 3 supports this
interpretation. The commentary on Common Article 3,
¶1(d), in its entirety states:
10                    HAMDAN v. RUMSFELD

                         ALITO, J., dissenting

       “[A]lthough [sentences and executions without a
       proper trial] were common practice until quite re
       cently, they are nevertheless shocking to the civilized
       mind. . . . Sentences and executions without previous
       trial are too open to error. ‘Summary justice’ may be
       effective on account of the fear it arouses . . . , but it
       adds too many further innocent victims to all the
       other innocent victims of the conflict. All civilized na
       tions surround the administration of justice with safe
       guards aimed at eliminating the possibility of judicial
       errors. The Convention has rightly proclaimed that it
       is essential to do this even in time of war. We must be
       very clear about one point: it is only ‘summary’ justice
       which it is intended to prohibit. No sort of immunity
       is given to anyone under this provision. There is
       nothing in it to prevent a person presumed to be
       guilty from being arrested and so placed in a position
       where he can do no further harm; and it leaves intact
       the right of the State to prosecute, sentence and pun
       ish according to the law.” GCIV Commentary 39 (em
       phasis added).
  It seems clear that the commissions at issue here meet
this standard. Whatever else may be said about the sys
tem that was created by Military Commission Order No. 1
and augmented by the Detainee Treatment Act,
§1005(e)(1), 119 Stat. 2742, this system—which features
formal trial procedures, multiple levels of administrative
review, and the opportunity for review by a United States
Court of Appeals and by this Court—does not dispense
“summary justice.”
                           *    *     * 

     For these reasons, I respectfully dissent. 

