 United States Court of Appeals
         FOR THE DISTRICT OF COLUMBIA CIRCUIT



Argued September 30, 2013              Decided July 14, 2014

                        No. 11-1324

         ALI HAMZA AHMAD SULIMAN AL BAHLUL,
                     PETITIONER

                              v.

                UNITED STATES OF AMERICA,
                       RESPONDENT


             On Petition for Rehearing En Banc


   Michel Paradis, Counsel, Office of the Chief Defense
Counsel, argued the cause for the petitioner. Mary R.
McCormick and Todd E. Pierce, Counsel, were on brief.

     David S. Weissbrodt and William J. Aceves were on brief
for amicus curiae International Law Scholars in support of the
petitioner.

     Agnieszka Fryszman was on brief for amicus curiae
National Institute of Military Justice in support of the
petitioner.

     McKenzie A. Livingston was on brief for amici curiae
Robert D. Steele and other Former Members of the
Intelligence Community in support of the petitioner.
                             2
     John S. Summers and Michael J. Newman were on brief
for amici curiae Professors David Glazier and Gary Solis in
support of the petitioner.

    Sarah H. Paoletti was on brief for amici curiae
Historians, Political Scientists and Constitutional Law
Scholars in support of the petitioner.

    Jeffrey T. Renz was on brief for amici curiae First
Amendment Scholars and Historians and the Montana Pardon
Project in support of the petitioner.

     Elizabeth B. Wydra was on brief for amicus curiae
Constitutional Accountability Center in support of the
petitioner.

     Ian H. Gershengorn, Attorney, U.S. Department of
Justice, argued the cause for the respondent. Steven M.
Dunne, Chief Attorney, and John F. De Pue, Attorney, were
on brief. Jeffrey M. Smith, Trial Attorney, U.S. Department
of Justice, and Francis A. Gilligan and Edward S. White,
Attorneys, Office of Military Commissions, entered
appearances.

    James A. Schoettler Jr. was on brief for amici curiae
Former Government Officials, Former Military Lawyers and
Scholars of National Security Law in support of respondent.

     Cory L. Andrews and Richard A. Samp were on brief for
amici curiae Washington Legal Foundation et al. in support of
the respondent.

    Before: GARLAND, Chief Judge, and HENDERSON,
ROGERS, TATEL, BROWN, GRIFFITH and KAVANAUGH, Circuit
Judges.
                              3

    Opinion for the court filed by Circuit Judge HENDERSON.

    Concurring opinion filed by Circuit Judge HENDERSON.

     Opinion concurring in the judgment in part and
dissenting filed by Circuit Judge ROGERS.

     Opinion concurring in the judgment in part and
dissenting in part filed by Circuit Judge BROWN.

     Opinion concurring in the judgment in part and
dissenting in part filed by Circuit Judge KAVANAUGH.

     KAREN LECRAFT HENDERSON, Circuit Judge: Ali Hamza
Ahmad Suliman al Bahlul (Bahlul) served as a personal
assistant to Osama bin Laden, produced propaganda videos
for al Qaeda and assisted with preparations for the attacks of
September 11, 2001 that killed thousands of Americans.
Three months after 9/11, Bahlul was captured in Pakistan and
transferred to the United States Naval Base at Guantanamo
Bay, Cuba. Military prosecutors charged him with three
crimes: conspiracy to commit war crimes, providing material
support for terrorism and solicitation of others to commit war
crimes. A military commission convicted him of all three
crimes and sentenced him to life imprisonment. The United
States Court of Military Commission Review (CMCR)
affirmed his conviction and sentence. Bahlul appeals. For the
reasons that follow, we reject Bahlul’s ex post facto challenge
to his conspiracy conviction and remand that conviction to the
original panel of this Court for it to dispose of several
remaining issues. In addition, we vacate his material support
and solicitation convictions.
                              4
                       I. Background

     Bahlul is a native of Yemen. In the late 1990s, he
traveled to Afghanistan to join al Qaeda. He completed
military-like training while staying at an al Qaeda guesthouse
and eventually met and pledged an oath of loyalty (“bayat”) to
bin Laden. Bin Laden assigned Bahlul to work in al Qaeda’s
media office.

     On October 12, 2000, al Qaeda suicide bombers attacked
the U.S.S. Cole, killing 17 American servicemen and
wounding 39 others. Bin Laden later instructed Bahlul to
create a video celebrating the attack for use as a recruiting
tool. The video Bahlul produced (and bin Laden edited)
includes footage of the attack, calls for jihad against the
United States and propaganda blaming “Western infidels” and
complicit Middle Eastern regimes for Muslim suffering.
Bahlul considered it one of the best propaganda videos al
Qaeda had produced and it has been translated into several
languages and widely distributed.

     Bin Laden then appointed Bahlul as his personal assistant
and secretary for public relations. Bahlul arranged the loyalty
oaths of two of the 9/11 hijackers, Mohamed Atta and Ziad al
Jarrah, and prepared their “martyr wills”—propaganda
declarations documenting al Qaeda’s role in the attacks.
Bahlul claims he sought to participate in the 9/11 attacks
himself but bin Laden refused because he considered his
media man too important to lose. In the days preceding 9/11,
Bahlul assembled al Qaeda’s media equipment and evacuated
al Qaeda’s Kandahar headquarters with bin Laden and other
senior al Qaeda leaders. They traveled to a remote region of
Afghanistan where, on September 11, 2001, they heard
reports of the day’s attacks via a radio operated by Bahlul.
                              5
Bin Laden subsequently asked Bahlul to research the
economic effects of the attacks and report his findings.

     In the following weeks, Bahlul fled to Pakistan. He was
captured there in December 2001 and turned over to U.S.
forces. In 2002, he was transferred to the U.S. Naval Base at
Guantanamo Bay, Cuba, where he has since been detained as
an enemy combatant pursuant to the 2001 Authorization for
Use of Military Force (AUMF). See Pub. L. No. 107-40,
§ 2(a), 115 Stat. 224, 224; Hamdi v. Rumsfeld, 542 U.S. 507,
518, 521 (2004) (plurality). Two months after 9/11, President
Bush invoked the AUMF and Article 21 of the Uniform Code
of Military Justice (UCMJ), 10 U.S.C. § 821 (hereinafter
“section 821”), to establish military commissions to try
“member[s] of . . . al Qaida” and others who “engaged in,
aided or abetted, or conspired to commit, acts of international
terrorism, or acts in preparation therefor.” See Detention,
Treatment, and Trial of Certain Non-Citizens in the War
Against Terrorism, 66 Fed. Reg. 57,833 (Nov. 13, 2001). In
2003, the President designated Bahlul eligible for trial by
military commission and in 2004 military prosecutors charged
him with conspiracy to commit war crimes.

     Bahlul’s prosecution was stayed pending the outcome of
another detainee’s challenge to the lawfulness of his trial by
military commission. In Hamdan v. Rumsfeld, the United
States Supreme Court held that the military commission
procedures then in place contravened certain constraints
imposed by the UCMJ and the four Geneva Conventions
signed in 1949. 548 U.S. 557, 613–35 (2006). In response to
the Hamdan decision, the Congress enacted the Military
Commissions Act of 2006 (2006 MCA), Pub. L. No. 109-336,
120 Stat. 2600, which amended the statutory procedures
governing military commissions to cure the flaws identified in
Hamdan. The 2006 MCA specifically enumerated 30 war
                               6
crimes triable by military commission, see 10 U.S.C. §§ 950t–
950v (2006),1 and conferred jurisdiction on military
commissions to try “any offense made punishable by this
chapter or the law of war when committed by an alien
unlawful enemy combatant before, on, or after September 11,
2001,” id. § 948d(a).

     The Supreme Court has long recognized that unlawful
enemy combatants may be prosecuted by military commission
for their war crimes. See Hamdan, 548 U.S. at 592–93;
Hamdi, 542 U.S. at 518; In re Yamashita, 327 U.S. 1, 7–8, 11
(1946); Ex parte Quirin, 317 U.S. 1, 28, 31 (1942). There are
three traditional bases for military commission jurisdiction:
military government, martial law and the law of war. See
Hamdan, 548 U.S. at 595–98 (plurality opinion); see also id.
at 683 (Thomas, J., dissenting). First, military commissions
may try ordinary crimes—e.g., manslaughter or robbery—and
violations of military orders committed by both soldiers and
civilians in territories under U.S. military government. Id. at
595–96. Second, military commissions may try ordinary
crimes and violations of military orders committed by soldiers
and civilians in territory under martial law—as much of our
country was during the Civil War. See id. at 595; WILLIAM
WINTHROP, MILITARY LAW AND PRECEDENTS 832–34 (rev. 2d
ed. 1920). Third, and “utterly different” from the first two
categories, military commissions may try offenses against the
law of war. Hamdan, 548 U.S. at 596 (plurality opinion)
(citation omitted). It is undisputed that the commission that
tried Bahlul is of the third type: a law-of-war military
    1
        The Military Commissions Act of 2009 rewrote the 2006
MCA but left it substantively unaltered as relevant here. See
National Defense Authorization Act for Fiscal Year 2010, Pub. L.
No. 111-84, §§ 1801–07, 123 Stat. 2190, 2574–2614 (codified at 10
U.S.C. §§ 948a–950t (Supp. III 2010)). Unless otherwise noted, we
refer to the 2006 MCA.
                               7
commission. A military commission convened pursuant to
the 2006 MCA must be composed of at least five “members,”
who are qualified active duty officers of the armed forces and
play a role similar to a petit jury. 10 U.S.C. §§ 948i, 948m.
A military judge presides over the trial. Id. § 948j.

     In 2008, military prosecutors amended the charges
against Bahlul to allege three of the offenses enumerated in
the 2006 MCA based on the conduct summarized above—
conspiracy to commit war crimes, providing material support
for terrorism and solicitation of others to commit war crimes.
See id. §§ 950u, 950v(b)(25), 950v(b)(28) (2006). The
conspiracy and solicitation charges alleged seven object
crimes proscribed by the 2006 MCA: murder of protected
persons, attacking civilians, attacking civilian objects, murder
in violation of the law of war, destruction of property in
violation of the law of war, terrorism and providing material
support for terrorism. See id. § 950v(b)(1)–(3), (15)–(16),
(24)–(25). Bahlul admitted all of the factual allegations
against him, with the exception of the allegation that he had
armed himself with a suicide belt to protect bin Laden. He
nevertheless pleaded not guilty to the charged offenses
because he denied the legitimacy of the military commission
and sought to absent himself from the proceedings as a
boycott. He objected to representation by appointed defense
counsel and expressed a desire to proceed pro se, although his
attempts to absent himself from the proceedings at times
complicated matters and forced defense counsel to stand in
for Bahlul and carry out his instructions not to present a
defense. Bahlul waived all pretrial motions, asked no
questions during voir dire, made no objections to prosecution
evidence, presented no defense and declined to make opening
and closing arguments.
                                 8
     The military commission convicted Bahlul of all three
offenses. Using a detailed findings worksheet, it found that
Bahlul conspired to commit and solicited each of the seven
alleged object offenses and that Bahlul committed ten of the
eleven alleged overt acts. See Petitioner’s Appendix (App.)
132–33.2      The commission sentenced him to life
imprisonment and the convening authority, Susan J.



    2
        The military commission specifically found that Bahlul
committed the following overt acts: (1) traveled to Afghanistan
with the purpose and intent of joining al Qaeda; (2) met with Saif al
Adl, the head of the al Qaeda Security Committee, as a step toward
joining al Qaeda; (3) underwent military-type training at an al
Qaeda sponsored training camp located in Afghanistan; (4) pledged
fealty or “bayat” to the leader of al Qaeda, Osama bin Laden, joined
al Qaeda and provided personal services in support of al Qaeda; (5)
prepared and assisted in the preparation of various propaganda
products, including the video “The Destruction of the American
Destroyer U.S.S. Cole,” to solicit material support for al Qaeda, to
recruit to and indoctrinate personnel about the organization and
objectives of al Qaeda and to solicit, incite and advise persons to
commit terrorism; (6) acted as personal secretary and media
secretary of bin Laden in support of al Qaeda; (7) arranged for
Muhammed Atta and Ziad al Jarrah to pledge fealty or “bayat” to
bin Laden; (8) prepared the propaganda declarations styled as
martyr wills of Atta and al Jarrah in preparation for the acts of
terrorism perpetrated by Atta, al Jarrah and others at various
locations in the United States on September 11, 2001; (9) at the
direction of bin Laden, researched the economic effect of the 9/11
attacks on the United States and provided the results of that
research to bin Laden; and (10) operated and maintained data
processing equipment and media communications equipment for
the benefit of bin Laden and other members of the al Qaeda
leadership. App. 132–33; see also id. at 122–23 (charging
document).
                                9
Crawford,3 approved the findings and sentence. The CMCR
affirmed Bahlul’s conviction and sentence in a 112-page
opinion. See United States v. Bahlul, 820 F. Supp. 2d 1141
(2011). Bahlul then appealed to this Court.

     While Bahlul’s appeal was pending, this Court held that
the 2006 MCA “does not authorize retroactive prosecution for
conduct committed before enactment of that Act unless the
conduct was already prohibited under existing U.S. law as a
war crime triable by military commission.” Hamdan v.
United States (Hamdan II), 696 F.3d 1238, 1248 (D.C. Cir.
2012) (emphasis in original). The Court declared that
providing material support for terrorism—the only charge at
issue in that appeal—was not a pre-existing war crime triable
by military commission; it therefore vacated Hamdan’s
conviction on that offense. Id. at 1248–53. The Government
subsequently conceded that Hamdan II’s reasoning required
vacatur of all three of Bahlul’s convictions. Based on that
concession, a panel of this Court vacated the convictions.
Order, Bahlul v. United States, No. 11-1324, 2013 WL
297726 (D.C. Cir. Jan. 25, 2013). We subsequently granted
the Government’s petition for rehearing en banc.



    3
        Under the 2006 MCA, a military commission “may be
convened by the Secretary of Defense or by any officer or official
of the United States designated by the Secretary for that purpose.”
10 U.S.C. § 948h. Crawford, a former judge of the United States
Court of Appeals for the Armed Forces, was so designated by the
Defense Secretary. The convening authority refers the charges
against the accused for trial by military commission, details the
members of the commission and approves or disapproves the
findings and sentence of the commission. Id. §§ 948i(b), 950b; cf.
Hamdan, 548 U.S. at 647–49 (Kennedy, J., concurring) (explaining
role of convening authority under UCMJ).
                              10
                    II. Standard of Review

    Bahlul argues that the 2006 MCA must be construed to
make triable by military commission only those crimes that
were recognized under the international law of war when
committed. He further contends that, if the 2006 MCA
authorizes retroactive prosecution of new law-of-war offenses
by military commission, his convictions violate the Ex Post
Facto Clause. Bahlul made neither of these arguments before
the military commission.

     “ ‘No procedural principle is more familiar to this Court
than that a constitutional right,’ or a right of any other sort,
‘may be forfeited in criminal as well as civil cases by the
failure to make timely assertion of the right before a tribunal
having jurisdiction to determine it.’ ” United States v. Olano,
507 U.S. 725, 731 (1993) (quoting Yakus v. United States,
321 U.S. 414, 444 (1944)). This fundamental principle of
appellate review generally bars a party who failed to preserve
an argument in a lower tribunal from raising it on appeal
absent plain error or exceptional circumstances. See United
States v. Atkinson, 297 U.S. 157, 159 (1936); Salazar ex rel.
Salazar v. Dist. of Columbia, 602 F.3d 431, 437 (D.C. Cir.
2010).

     To preserve error for appellate review, an appellant must
interpose a “timely” objection, United States v. Simpson, 430
F.3d 1177, 1183 (D.C. Cir. 2005), and “state the specific
ground for [the] objection,” United States v. Boyd, 54 F.3d
868, 872 (D.C. Cir. 1995). Although he need not “cite the
particular case that supports his position,” United States v.
Rashad, 396 F.3d 398, 401 (D.C. Cir. 2005), he must state the
ground for his objection “with sufficient precision to indicate
distinctly [his] thesis,” Miller v. Avirom, 384 F.2d 319, 322
(D.C. Cir. 1967). Thus, “[a]n objection is not properly raised
                              11
if it is couched in terms too general to have alerted the trial
court to the substance of the petitioner’s point.” United States
v. Breedlove, 204 F.3d 267, 270 (D.C. Cir. 2000); see also
Noonan v. Caledonia Gold Min. Co., 121 U.S. 393, 400
(1887) (“The rule is universal, that where an objection is so
general as not to indicate the specific grounds upon which it is
made, it is unavailing on appeal, unless it be of such a
character that it could not have been obviated at the trial.”).

      The contemporaneous-objection rule is not mere
“obeisance to ritual.” Miller, 384 F.2d at 322. It serves two
purposes. First, the rule promotes judicial efficiency by
giving the trial tribunal the opportunity to quickly and
efficiently resolve errors that would otherwise require
burdensome and unnecessary appellate review and remand.
See Puckett v. United States, 556 U.S. 129, 134 (2009).
Second, the rule discourages the intentional withholding of an
objection by a party to be raised on appeal only if he loses at
trial. See id.; see also Wainwright v. Sykes, 433 U.S. 72, 89
(1977); Hormel v. Helvering, 312 U.S. 552, 556 (1941);
United States v. Socony-Vacuum Oil Co., 310 U.S. 150, 238–
39 (1940) (citing Crumpton v. United States, 138 U.S. 361,
364 (1891)).

     To mitigate the sometimes harsh results of the forfeiture
rule in criminal cases, the Congress authorizes the court of
appeals to exercise its discretion to notice and correct a
certain type of forfeited error: “plain error.” FED. R. CRIM. P.
52(b); see United States v. Young, 470 U.S. 1, 15 (1985); see
also 10 U.S.C. § 950a(a) (Supp. III 2010) (Military
Commissions Act of 2009 review provision specifying that
only errors that “materially prejudice[] the substantial rights
                                 12
of the accused” may be corrected).4 A plain error is “[1] an
‘error’ [2] that is ‘plain’ and [3] that ‘affect[s] substantial
rights.’ ” Olano, 507 U.S. at 732 (quoting FED. R. CRIM P.
52(b)) (final alteration in original). “If all three conditions are
met, an appellate court may then exercise its discretion to
notice a forfeited error, but only if (4) the error seriously
affects the fairness, integrity, or public reputation of judicial
proceedings.” Johnson v. United States, 520 U.S. 461, 467
(1997) (quotation marks and brackets omitted). Plain-error
review, however, is “highly circumscribed.” United States v.
Brinson-Scott, 714 F.3d 616, 625 (D.C. Cir. 2013); see also
Puckett, 556 U.S. at 134 (“Meeting all four prongs is difficult,
as it should be.” (quotation marks omitted)); Young, 470 U.S.
at 15 (“[T]he plain-error exception to the contemporaneous-
objection rule is to be used sparingly, solely in those
circumstances in which a miscarriage of justice would
otherwise result.” (quotation marks omitted)). “There is good
reason for this; anyone familiar with the work of courts
understands that errors are a constant in the trial process, that
most do not much matter, and that a reflexive inclination by
appellate courts to reverse because of unpreserved error
would be fatal” to the policies furthered by the
contemporaneous-objection rule. Puckett, 556 U.S. at 134
(quotation marks omitted). We therefore must guard against
“unwarranted extension of this exacting definition of plain
error.” Young, 470 U.S. at 15.5

    4
       We need not decide whether Rule 52(b) applies directly to
this proceeding because plain-error review is appropriate whether
or not Rule 52(b) directly governs. See Salazar, 602 F.3d at 437.
    5
       The Government argued for plain-error review before the
CMCR, in its original brief to a panel of this Court and in its brief
to the en banc court. See Bahlul, 820 F. Supp. 2d at 1256–58; Br.
of the United States 65, Bahlul v. United States, No. 11-1324 (D.C.
Cir. May 16, 2012) (Panel Br.); Br. of the United States 63, Bahlul
                                13

     Applying these principles here, we conclude that Bahlul
forfeited the arguments he now raises. He flatly refused to
participate in the military commission proceedings and
instructed his trial counsel not to present a substantive
defense. Although he objected to the commission’s authority
to try him, his objection was couched entirely in political and
religious terms. He disclaimed guilt and contended that “what
[he] did was not a crime.” Trial Tr. 175. But context makes
clear that Bahlul argued that his acts were not criminal
because they were inspired by religious fervor. See id. at
175–76. After claiming that the United States had “put on the
side[] the meaningless American laws” and “legislated new
laws” for “the planet Earth,” he explained that he “believe[s]
that no one has the right in the land to set laws for the people,
the right of legislating laws[] is absolutely to Allah, the All
Mighty.” Id. at 23–24. Bahlul did ask a “legal question”
about whether the “law here by you stems from the action,
before action, or post action,” id. at 104, but the military
judge could not ascertain what Bahlul was asking and Bahlul
did not elaborate. Bahlul’s objection to the commission’s
authority was unquestionably “too general to have alerted the
trial court to the substance of [his] point.” United States v.
Bolla, 346 F.3d 1148, 1152 (D.C. Cir. 2003) (Roberts, J.)


v. United States, No. 11-1324 (D.C. Cir. July 10, 2013) (E.B. Br.).
We reject Bahlul’s contention that the Government abandoned its
forfeiture argument by conceding in its supplemental brief to the
panel after Hamdan II that Bahlul’s convictions should be vacated.
That brief was directed to a panel of this Court, which was bound
by Hamdan II’s avoidance of the ex post facto issue. See Hamdan
II, 696 F.3d at 1248 n.7. Only at the en banc stage was it possible
for the Government to attack Hamdan II’s statutory construction
and therefore put the Ex Post Facto Clause—and the applicable
standard of review—back in play.
                                14
(quotation marks omitted); Breedlove, 204 F.3d at 270.
Accordingly, we review his convictions for plain error.6

    6
        Three of our colleagues cite Rules 905 and 907 of the Rules
of Military Commissions for the notion that Bahlul’s ex post facto
argument is “not forfeitable.” Opinion of Judge Kavanaugh
(Kavanaugh Op.) 31; accord Opinion of Judge Rogers (Rogers Op.)
26–27; Opinion of Judge Brown (Brown Op.) 2. Bahlul’s briefs do
not mention these rules or suggest this argument. Moreover, Rules
905 and 907 both explicitly refer to waiver, see MANUAL FOR
MILITARY COMMISSIONS, pt. II, at 83–84, 87 (2007), whereas we
conclude instead that Bahlul forfeited his argument. “Although
jurists often use the words interchangeably,” Kontrick v. Ryan, 540
U.S. 443, 458 n.13 (2004), waiver and forfeiture are not the same,
see Olano, 507 U.S. at 733; see also United States v. Weathers, 186
F.3d 948, 955 (D.C. Cir. 1999) (explaining difference while
interpreting similar provision in Federal Rules of Criminal
Procedure regarding waiver of pretrial motions). Nor is Bahlul’s ex
post facto argument “jurisdictional.” See Rogers Op. 26; Brown
Op. 2; Kavanaugh Op. 31. As discussed infra pp. 16–17, the 2006
MCA explicitly confers jurisdiction on military commissions to try
the charged offenses.        The question whether that Act is
unconstitutional does not involve “ ‘the courts’ statutory or
constitutional power to adjudicate the case.’ ” United States v.
Cotton, 535 U.S. 625, 630 (2002) (quoting Steel Co. v. Citizens for
a Better Env’t, 523 U.S. 83, 89 (1998)); United States v. Williams,
341 U.S. 58, 66 (1951) (“Even the unconstitutionality of the statute
under which the proceeding is brought does not oust a court of
jurisdiction.”); Lamar v. United States, 240 U.S. 60, 65 (1916)
(“The objection that the indictment does not charge a crime against
the United States goes only to the merits of the case.”); see also
United States v. Delgado-Garcia, 374 F.3d 1337, 1342–43 (D.C.
Cir. 2004) (explaining limits of so-called “Blackledge/Menna”
exception relied on by Bahlul). Nor are we persuaded that Bahlul’s
ex post facto argument is non-forfeitable because it amounts to an
argument that the indictment fails to “allege an offense.” Rogers
Op. 27; Kavanaugh Op. 32. Failure to state an offense is simply
another way of saying there is a defect in the indictment—as
                                 15
     Two of our colleagues contend that, by applying only
plain-error review, we have provided insufficient clarity in
this case. They argue that the Executive Branch’s need for
guidance in this area warrants de novo review. Brown Op. 1,
24; Kavanaugh Op. 34. But the Government itself has asked
that we apply plain-error review. E.B. Br. of the United
States 63. Indeed, at oral argument, it insisted that we do so,
notwithstanding the potential lack of “clarity” that such
review might entail. Oral Arg. Tr. 45.

                     III. Statutory Analysis

     As noted, Hamdan II held that the 2006 MCA “does not
authorize retroactive prosecution for conduct committed
before enactment of that Act unless the conduct was already
prohibited under existing U.S. law as a war crime triable by
military commission.” 696 F.3d at 1248. Because we
conclude, for the reasons that follow, that the 2006 MCA is
unambiguous in its intent to authorize retroactive prosecution
for the crimes enumerated in the statute—regardless of their
pre-existing law-of-war status—we now overrule Hamdan
II’s statutory holding. See United States v. Burwell, 690 F.3d
500, 504 (D.C. Cir. 2012) (en banc); Critical Mass Energy
Project v. NRC, 975 F.2d 871, 876 (D.C. Cir. 1992) (en banc);




evidenced by Rule 907’s cross-reference to Rule 307(c), which sets
forth the criteria for charges and specifications. See MANUAL FOR
MILITARY COMMISSIONS, pt. II, at 15–16; see also Delgado-
Garcia, 374 F.3d at 1341–42 (“[T]he question of an indictment’s
failure to state an offense is an issue that goes to the merits of a
case . . . .”). As Cotton makes clear, such a claim can be forfeited.
535 U.S. at 630–31.
                                 16
Save Our Cumberland Mountains, Inc. v. Hodel, 857 F.2d
1516, 1524 (D.C. Cir. 1988) (en banc).7

              A. The 2006 MCA is Unambiguous

     The 2006 MCA confers jurisdiction on military
commissions to try “any offense made punishable by this
chapter or the law of war when committed by an alien
unlawful enemy combatant before, on, or after September 11,
2001.” 10 U.S.C. § 948d(a) (2006) (emphases added).
“Any,” in this context, means “all.” See OXFORD ENGLISH
DICTIONARY 539 (2d ed. 1989) (“indifference as to the
particular one or ones that may be selected”); see also Dep’t
of Housing & Urban Dev. v. Rucker, 535 U.S. 125, 131
(2002); United States v. Gonzales, 520 U.S. 1, 5 (1997). The
“offense[s] made punishable by this chapter” include the
charges of which Bahlul was convicted: conspiracy to commit
war crimes, providing material support for terrorism and
solicitation of others to commit war crimes. 10 U.S.C.
§§ 950u, 950v(b)(25), 950v(b)(28) (2006). There could
hardly be a clearer statement of the Congress’s intent to
confer jurisdiction on military commissions to try the
enumerated crimes regardless whether they occurred “before,
on, or after September 11, 2001.” And the provisions of the
statute enumerating the crimes triable thereunder expressly
“do not preclude trial for crimes that occurred before the date
of the enactment of this chapter.” 10 U.S.C. § 950p(b)
(2006). For good reason: If it were otherwise, section 948d’s
conferral of jurisdiction to prosecute the enumerated crimes
occurring on or before September 11, 2001 would be
    7
       Although perhaps uncommon, overruling our precedent on
plain-error review is within the authority of the en banc court. See,
e.g., United States v. Padilla, 415 F.3d 211, 217–18 (1st Cir. 2005)
(en banc) (recognizing power of en banc court to overrule circuit
precedent under plain-error review but declining to do so).
                              17
inoperative. See Corley v. United States, 556 U.S. 303, 314
(2009) (“A statute should be construed so that effect is given
to all its provisions, so that no part will be inoperative or
superfluous, void or insignificant.” (quotation marks, brackets
and ellipsis omitted)). Although we presume that statutes
apply only prospectively “absent clear congressional intent”
to the contrary, that presumption is overcome by the clear
language of the 2006 MCA. Landgraf v. USI Film Prods.,
511 U.S. 244, 280 (1994); see also Johnson v. United States,
529 U.S. 694, 701 (2000) (clear statement of intent overcomes
presumption against retroactivity); Martin v. Hadix, 527 U.S.
343, 353–54 (1999) (“ ‘unambiguous directive’ or ‘express
command’ ” overcomes presumption against retroactivity);
Reynolds v. M’Arthur, 27 U.S. (2 Pet.) 417, 434 (1829)
(Marshall, C.J.) (“[L]aws by which human action is to be
regulated . . . are never to be construed retrospectively unless
the language of the act shall render such construction
indispensable.”).

     Review of the inter-branch dialogue which brought about
the 2006 MCA confirms the Congress’s intent to apply all of
the statute’s enumerated crimes retroactively.            See
Boumediene v. Bush, 553 U.S. 723, 738 (2008)
(“acknowledg[ing] . . . the litigation history that prompted
Congress to enact the MCA”). In Hamdan v. Rumsfeld, 548
U.S. 557 (2006), the Supreme Court considered the
President’s order that a military commission try Hamdan, a
Guantanamo detainee, for one of the very crimes of which
Bahlul was convicted: conspiracy to commit war crimes.
Hamdan challenged the President’s authority to convene the
military commission by petitioning for habeas corpus relief
and the Supreme Court’s resulting decision initiated two
games of interpretive ping-pong between the judiciary and the
legislature. One involves the issue presented here: whether
conspiracy is triable by a law-of-war military commission. In
                             18
Hamdan, four justices concluded that it was not triable under
the extant statute (section 821) and three concluded that it
was. Compare Hamdan, 548 U.S. at 603–13 (plurality
opinion of Stevens, J.), with id. at 697–704 (Thomas, J.,
dissenting). Four justices also “specifically invited Congress
to clarify the scope of the President’s statutory authority to
use military commissions to try unlawful alien enemy
combatants for war crimes.” Hamdan II, 696 F.3d at 1243;
see Hamdan, 548 U.S. at 636 (Breyer, J., concurring)
(“Nothing prevents the President from returning to Congress
to seek the authority he believes necessary.”); id. at 637
(Kennedy, J., concurring) (“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 prerogative to do so.”).

     The Congress answered the Court’s invitation with the
2006 MCA, which provides the President the very power he
sought to exercise in Hamdan—the power to try the 9/11
perpetrators for conspiracy—by including conspiracy as an
offense triable by military commission, 10 U.S.C.
§ 950v(b)(28) (2006), and by conferring jurisdiction on
military commissions to try alien unlawful enemy combatants
for conspiracy based on conduct that occurred “before, on, or
after September 11, 2001,” id. § 948d(a). We must heed this
inter-branch dialogue, as Boumediene instructs. 553 U.S. at
738.

     If this sounds familiar, it does so because it mirrors a
second game of interpretive ping-pong begun in Hamdan.
There, the Court also addressed the Government’s contention
that section 1005(e)(1) of the Detainee Treatment Act of 2005
(DTA), Pub. L. 109-148, 119 Stat. 2739, 2741–42—enacted
after the Court’s grant of certiorari in Hamdan—ousted it of
jurisdiction to entertain Hamdan’s habeas petition. Hamdan,
                               19
548 U.S. at 572. After a lengthy statutory analysis, the Court
construed the DTA to apply only to petitions filed after the
DTA’s enactment and, because Hamdan’s petition was filed
before, the statute did not apply. Id. at 576–84. In construing
the DTA as it did, the Court avoided addressing “grave
questions about Congress’ authority to impinge upon this
Court’s appellate jurisdiction, particularly in habeas cases”
and whether the Congress had unconstitutionally suspended
the writ of habeas corpus. Id. at 575. Although the Court
relied on “[o]rdinary principles of statutory construction” to
reach its result, id., its practical message to the Congress was
clear: Stripping the courts of jurisdiction over detainees’
pending habeas petitions must be done unambiguously. Three
justices dissented, arguing that the DTA was already
unambiguous in its intent to repeal the Court’s jurisdiction.
Id. at 656–69 (Scalia, J., dissenting).

     The Congress returned serve in the 2006 MCA. Section
7(b) clarified that the bar to habeas jurisdiction applied to “all
cases, without exception, pending on or after the date” of the
statute’s enactment. 2006 MCA, § 7(b), 120 Stat. at 2636.
Two years later, a detainee whose habeas petition was
pending at the time of the 2006 MCA’s enactment argued that
the statute did not apply to his case because section 7(b) was
not a “sufficiently clear statement of congressional intent to
strip the federal courts of jurisdiction in pending cases.”
Boumediene, 553 U.S. at 737. This time, the Court rejected
the argument. It explained:

    If the Court invokes a clear statement rule to advise
    that certain statutory interpretations are favored in
    order to avoid constitutional difficulties, Congress
    can make an informed legislative choice either to
    amend the statute or to retain its existing text. If
    Congress amends, its intent must be respected even if
                               20
    a difficult constitutional question is presented. The
    usual presumption is that Members of Congress, in
    accord with their oath of office, considered the
    constitutional issue and determined the amended
    statute to be a lawful one; and the Judiciary, in light
    of that determination, proceeds to its own
    independent judgment on the constitutional question
    when required to do so in a proper case.

    If this ongoing dialogue between and among the
    branches of Government is to be respected, we
    cannot ignore that the MCA was a direct response to
    Hamdan’s holding that the DTA’s jurisdiction-
    stripping provision had no application to pending
    cases.

Id. at 738 (emphases added). Having avoided the Suspension
Clause issue in Hamdan by virtue of its construction of the
statute and having been answered by the Congress’s
reenactment of its retroactive intent, the Court had no choice
but to resolve the difficult constitutional question presented
(whether the MCA violated the Suspension Clause).

     The same thing happened here. In enacting the military
commission provisions of the 2006 MCA, the Congress
plainly intended to give the President the power which
Hamdan held it had not previously supplied—just as the 2006
MCA clarified that in fact the Congress did intend section
7(b)’s ouster of habeas jurisdiction to apply to pending cases.
The legislative history confirms this view. See Boumediene,
553 U.S. at 739 (“The Court of Appeals was correct to take
note of the legislative history when construing the statute . . .
.”). Supporters and opponents of the legislation alike agreed
that the 2006 MCA’s purpose was to authorize the trial by
                                 21
military commission of the 9/11 conspirators.8 And because
the 9/11 conspiracy took place long before 2006, the statute
could accomplish its explicit purpose only if it applied to pre-
enactment conduct. As the Court itself made clear, “we
cannot ignore that the [2006] MCA was a direct response to
Hamdan’s holding.” Boumediene, 553 U.S. at 739.

    Reading the MCA in this context and given the
unequivocal nature of its jurisdictional grant, we conclude the


     8
        The legislative history is overwhelmingly in favor of
retroactive application of the MCA’s provisions as a response to
Hamdan. See, e.g., 152 CONG. REC. H7533 (daily ed. Sept. 27,
2006) (statement of Rep. Hunter) (“I can’t think of a better way to
honor the fifth anniversary of September 11 than by establishing a
system to prosecute the terrorists who on that day murdered
thousands of innocent civilians . . . .”); id. (“Without [the 2006
MCA], the United States has no effective means to try and punish
the perpetrators of September 11, the attack on the USS Cole and
the embassy bombings.”); id. at H7536 (statement of Rep. Saxton)
(“We have carefully narrowed and crafted the provisions of this bill
to enable the United States to prosecute the perpetrators of the 1998
bombings of the American embassies in Kenya and Tanzania, the
2000 attack on the USS Cole, and other crimes that have been
committed.”); id. (“Importantly, this bill allows, as all Americans
believe it should, the criminal prosecutions of those who
purposefully and materially supported [the 9/11 conspiracy].”); id.
at H7545 (statement of Rep. Sensenbrenner) (“[The 2006 MCA] is
about prosecuting the most dangerous terrorists America has ever
confronted . . . like Khalid Sheik Mohammed, the mastermind of
the 9/11 attacks, or Ahbd al-Nashiri, who planned the attack on the
USS Cole.”); id. at H7552 (statement of Rep. Boehner); id. at
S10243 (statement of Sen. Frist) (“Until Congress passes [the 2006
MCA], terrorists such as Khalid Shaikh Mohammed cannot be tried
for war crimes . . . .”); cf. id. at H7536 (statement of Rep. Skelton)
(opposing 2006 MCA because it “creates” “ex post facto laws”).
                              22
2006 MCA unambiguously authorizes Bahlul’s prosecution
for the charged offenses based on pre-2006 conduct.

          B. The Avoidance Canon is Inapplicable

    Hamdan II’s contrary conclusion turned on the following
provision of the 2006 MCA:

         (a) PURPOSE.—The provisions of this subchapter
    codify offenses that have traditionally been triable by
    military commissions. This chapter does not
    establish new crimes that did not exist before its
    enactment, but rather codifies those crimes for trial
    by military commission.

         (b) EFFECT.—Because the provisions of this
    subchapter (including provisions that incorporate
    definitions in other provisions of law) are declarative
    of existing law, they do not preclude trial for crimes
    that occurred before the date of the enactment of this
    chapter.

10 U.S.C. § 950p (2006). In Hamdan II, the Court read this
provision to reflect the Congress’s “belie[f] that the Act
codified no new crimes and thus posed no ex post facto
problem.” 696 F.3d at 1247. Because the Congress was
wrong in its textually stated premise—i.e., the Act did codify
new war crimes—the Court found “at least something of an
ambiguity” in the statute. Id. at 1248. It then turned to the
avoidance canon to resolve the ambiguity, concluding that the
Congress intended to authorize retroactive prosecution only if
“the conduct was already prohibited under existing U.S. law
as a war crime triable by military commission.” Id.
                               23
     The “avoidance canon” reflects a fundamental principle
of judicial restraint. See Ashwander v. TVA, 297 U.S. 288,
341–48 (1936) (Brandeis, J., concurring). But “[t]he canon of
constitutional avoidance comes into play only when, after the
application of ordinary textual analysis, the statute is found to
be susceptible of more than one construction; and the canon
functions as a means of choosing between them.” Clark v.
Martinez, 543 U.S. 371, 385 (2005) (emphasis in original);
see also Milavetz, Gallop & Milavetz, P.A. v. United States,
559 U.S. 229, 239 (2010). If, after applying ordinary
principles of textual analysis, the statute is not genuinely open
to two constructions, the “canon of constitutional avoidance
does not apply.” Gonzales v. Carhart, 550 U.S. 124, 154
(2007). Because the 2006 MCA unqualifiedly confers
jurisdiction on military commissions to try “any offense made
punishable by this chapter or the law of war when committed
by an alien unlawful enemy combatant before, on, or after
September 11, 2001,” 10 U.S.C. § 948d(a) (2006) (emphases
added), it is not “fairly possible” to read the statute to apply
only prospectively. United States v. Jin Fuey Moy, 241 U.S.
394, 401 (1916) (Holmes, J.).

     Hamdan II perceived a “tight causal link between (i)
Congress’s belief that the statute codified only crimes under
pre-existing law and (ii) Congress’s statement that the new
statute could therefore apply to conduct before enactment.”
696 F.3d at 1247–48. We think that link plainly affirms the
Congress’s intent to apply the statute retroactively. “The
Congress is a coequal branch of government whose Members
take the same oath we do to uphold the Constitution of the
United States.” Rostker v. Goldberg, 453 U.S. 57, 64 (1981).
We assume that, in meeting that oath, it “legislates in the light
of constitutional limitations.” Rust v. Sullivan, 500 U.S. 173,
191 (1991); see also Edward J. DeBartolo Corp. v. Fla. Gulf
Coast Bldg. & Constr. Trades Council, 485 U.S. 568, 575
                              24
(1988); FTC v. Am. Tobacco Co., 264 U.S. 298, 305–06
(1924); United States v. Harris, 106 U.S. 629, 635 (1883);
Joint Anti-Fascist Refugee Comm. v. McGrath, 341 U.S. 123,
164 (1951) (Frankfurter, J., concurring). As section 950p
makes abundantly clear, the Congress made precisely that
assessment and, whether right or wrong, concluded that the
statute fell within the constitutional limits of its legislative
authority. See City of Boerne v. Flores, 521 U.S. 507, 535
(1997) (“When Congress acts within its sphere of power and
responsibilities, it has not just the right but the duty to make
its own informed judgment on the meaning and force of the
Constitution.”); United States v. Nixon, 418 U.S. 683, 703
(1974) (“In the performance of assigned constitutional duties
each branch of the Government must initially interpret the
Constitution, and the interpretation of its powers by any
branch is due great respect from the others.”). Indeed, the
legislative history reveals the breadth of the Congress’s
debate on the statute’s constitutionality. See, e.g., H.R. Rep.
No. 109-664, at 25 (“For the reasons stated in Justice
Thomas’s opinion [in Hamdan], the Committee [on Armed
Services] views conspiracy as a separate offense punishable
by military commissions.”).

     The “ambiguity” Hamdan II identified was the
Congress’s failure to address what it “would . . . have wanted”
if it “had known that the Act was codifying some new
crimes.” 696 F.3d at 1247. In other words, Hamdan II found
the statute ambiguous because the Congress did not include in
the text of the statute alternative language in case it was
wrong in its reading of the law on which it premised its
legislation. But the Congress always legislates on the basis of
some set of facts or premises it believes to be true. It holds
hearings and investigates precisely for the purpose of
acquiring facts and then legislates on the basis of those facts.
Because it believes to be true the facts on which it bases its
                               25
legislation, the Congress seldom (if ever) includes instructions
on what to do if those facts are proven incorrect. Here, the
Congress authorized prosecution for “any offense made
punishable by” the 2006 MCA, including offenses based on
pre-enactment conduct, precisely because it believed that all
of the offenses were already triable by military commission.
The Congress’s plainly expressed belief about pre-enactment
law should govern our understanding of the Congress’s intent
expressed in the text of the statute. If judicial inquiry reveals
that the Congress was mistaken, it is not our task to rewrite
the statute to conform with the actual state of the law but
rather to strike it down insofar as the Congress’s mistake
renders the statute unconstitutional. See Ass’n of Am.
Railroads v. U.S. Dep’t of Transp., 721 F.3d 666, 673 n.7
(D.C. Cir. 2013) (“The constitutional avoidance canon is an
interpretive aid, not an invitation to rewrite statutes to satisfy
constitutional strictures.”), cert. granted (June 23, 2014).

     Moreover, the avoidance canon ordinarily requires no
speculation into the Congress’s hypothetical intent: If the
statute’s text is ambiguous, we choose a constitutional
construction over an unconstitutional one. Here, however, the
“ambiguity” lies not in the text itself but in the text when read
in light of Hamdan II’s subsequent finding that the premise on
which the text is based is wrong. That is, the “ambiguity” lies
in the existence of matters unknown to the Congress. But
“[w]e cannot replace the actual text with speculation as to
Congress’ intent,” Magwood v. Patterson, 130 S. Ct. 2788,
2798 (2010), nor can we “divin[e] what Congress would have
wanted if it had thought of the situation before the court,”
Morrison v. Nat’l Australia Bank Ltd., 130 S. Ct. 2869, 2881
(2010); see also United States v. Public Utilities Comm’n of
Cal., 345 U.S. 295, 319 (1953) (Jackson, J., concurring)
(“Never having been a Congressman, I am handicapped in
that weird endeavor. That process seems to me not
                               26
interpretation of a statute but creation of a statute.”). For that
reason, “our inquiry focuses on an analysis of the textual
product of Congress’ efforts, not on speculation as to the
internal thought processes of its Members.” Carter v. United
States, 530 U.S. 255, 272 (2000); see also Gardner v. Collins,
27 U.S. (2 Pet.) 58, 93 (1829) (“What the legislative intention
was, can be derived only from the words they have used; and
we cannot speculate beyond the reasonable import of these
words.”).

     Even if it may raise difficult constitutional questions, the
statutory text remains the gravamen of our interpretive
inquiry. See United States v. Raynor, 302 U.S. 540, 552
(1938). “Although [we] will often strain to construe
legislation so as to save it against constitutional attack,”
Aptheker v. Sec’y of State, 378 U.S. 500, 515 (1964)
(quotation marks omitted), a court cannot “rewrite a law to
conform it to constitutional requirements, for doing so would
constitute a serious invasion of the legislative domain,”
United States v. Stevens, 559 U.S. 460, 481 (2010) (quotation
marks, ellipsis and citations omitted). “Here the intention of
the Congress is revealed too distinctly to permit us to ignore it
because of mere misgivings as to power. The problem must
be faced and answered.” George Moore Ice Cream Co. v.
Rose, 289 U.S. 373, 379 (1933) (Cardozo, J.).

            IV. Bahlul’s Ex Post Facto Challenge

    Because the Congress’s intent to authorize retroactive
prosecution of the charged offenses is clear, we must address
Bahlul’s ex post facto argument. See Cohens v. Virginia, 19
U.S. (6 Wheat.) 264, 404 (1821) (Marshall, C.J.) (“Questions
may occur which we would gladly avoid; but we cannot avoid
them. All we can do is, to exercise our best judgment, and
conscientiously to perform our duty.”). As noted, we may
                              27
overturn Bahlul’s convictions only if they constitute plain
constitutional error.

    The Constitution prohibits the Congress from enacting
any “ex post facto Law.” U.S. CONST. art. I, § 9, cl. 3. “The
phrase ex post facto law was a term of art with an established
meaning at the time of the framing.” Peugh v. United States,
133 S. Ct. 2072, 2081 (2013) (quoting Collins v. Youngblood,
497 U.S. 37, 41 (1990)) (quotation marks omitted). In Calder
v. Bull, Justice Chase set forth his understanding of that
meaning:

    1st. Every law that makes an action, done before the
    passing of the law, and which was innocent when
    done, criminal; and punishes such action. 2nd. Every
    law that aggravates a crime, or makes it greater than
    it was, when committed. 3rd. Every law that changes
    the punishment, and inflicts a greater punishment,
    than the law annexed to the crime, when committed.
    4th. Every law that alters the legal rules of evidence,
    and receives less, or different, testimony, than the
    law required at the time of the commission of the
    offence, in order to convict the offender.

3 U.S. (3 Dall.) 386, 390 (1798) (opinion of Chase, J.); see
Peugh, 133 S. Ct. at 2081 (reciting Justice Chase’s
formulation); Carmell v. Texas, 529 U.S. 513, 525 (2000)
(Supreme Court has “repeatedly endorsed” Justice Chase’s
formulation); see also id. at 537–39 (noting that Collins did
not eliminate Justice Chase’s fourth category).

     In our order granting en banc review, we asked the
parties to brief whether the Ex Post Facto Clause applies in
cases involving aliens detained at Guantanamo.          The
Government has taken the position that it does. Although we
                               28
are not obligated to accept the Government’s concession, see
Young v. United States, 315 U.S. 257, 258–59 (1942); United
States v. Baldwin, 563 F.3d 490, 491 (D.C. Cir. 2009), we
will assume without deciding that the Ex Post Facto Clause
applies at Guantanamo. In so doing, we are “not to be
understood as remotely intimating in any degree an opinion
on the question.” Petite v. United States, 361 U.S. 529, 531
(1960) (per curiam); see also Casey v. United States, 343 U.S.
808, 808 (1952) (per curiam) (“To accept in this case [the
Solicitor General’s] confession of error would not involve the
establishment of any precedent.”); United States v. Bell, 991
F.2d 1445, 1447–48 (8th Cir. 1993).9

                         A. Conspiracy

     We reject Bahlul’s ex post facto challenge to his
conspiracy conviction for two independent and alternative
reasons. First, the conduct for which he was convicted was
already criminalized under 18 U.S.C. § 2332(b) (section
2332(b)) when Bahlul engaged in it. It is not “plain” that it
violates the Ex Post Facto Clause to try a pre-existing federal
criminal offense in a military commission and any difference
between the elements of that offense and the conspiracy
charge in the 2006 MCA does not seriously affect the
fairness, integrity or public reputation of judicial proceedings.
Second, it is not “plain” that conspiracy was not already


    9
        Were we to decide this issue de novo, Judge Henderson
would conclude that the Ex Post Facto Clause does not apply in
cases involving aliens detained at Guantanamo, for the reasons
stated in her separate concurring opinion. Chief Judge Garland and
Judges Tatel and Griffith would conclude that the Clause does
apply in such cases, for the reasons stated in the first two
paragraphs of Part II.B of Judge Rogers’s opinion and in Note 3 of
Judge Kavanaugh’s opinion.
                                29
triable by law-of-war military commission under 10 U.S.C.
§ 821 when Bahlul’s conduct occurred.

                       1. Section 2332(b)

     Bahlul was convicted of conspiracy to commit seven war
crimes enumerated in the 2006 MCA, including the murder of
protected persons.10 Although the 2006 MCA post-dates
Bahlul’s conduct, section 2332(b) has long been on the books,
making it a crime to, “outside the United States,” “engage[] in
a conspiracy to kill[] a national of the United States.” 18
U.S.C. § 2332(b); see Omnibus Diplomatic Security and
Antiterrorism Act of 1986, Pub. L. No. 99-399, § 1202(a),
100 Stat. 853, 896. Section 2332(b) is not an offense triable
by military commission but, the Government argues, “[t]he
fact that the MCA provides a different forum for adjudicating
such conduct does not implicate ex post facto concerns.” E.B.
Br. of United States 67. We agree. See infra p. 53
(remanding to panel to determine Bahlul’s other constitutional
challenges).

     The right to be tried in a particular forum is not the sort
of right the Ex Post Facto Clause protects. See Collins, 497
U.S. at 51. In Collins, the Supreme Court sifted through its
Ex Post Facto Clause precedent, noting that some cases had

    10
        Specifically, the 2006 MCA provides: “Any person subject
to this chapter who conspires to commit one or more substantive
offenses triable by military commission under this chapter, and who
knowingly does any overt act to effect the object of the conspiracy,
shall be punished . . . .” 10 U.S.C. § 950v(b)(28). The murder of
protected persons is the “intentional[]” killing of one or more
“protected persons.” Id. § 950v(b)(1). A protected person is “any
person entitled to protection under one or more of the Geneva
Conventions, including . . . civilians not taking an active part in
hostilities.” Id. § 950v(a)(2)(A).
                                30
said that a “procedural” change—i.e., a “change[] in the
procedures by which a criminal case is adjudicated”—may
violate the Ex Post Facto Clause if the change “affects
matters of substance” by “depriving a defendant of substantial
protections with which the existing law surrounds the person
accused of crime or arbitrarily infringing upon substantial
personal rights.” Id. at 45 (citations, brackets and quotation
marks omitted). The Court observed that such language had
“imported confusion” into its doctrine and it attempted to
reconcile that language so as to not enlarge the Ex Post Facto
Clause’s application beyond laws that “make innocent acts
criminal, alter the nature of the offense, or increase the
punishment.” Id. at 46. One case that could not be reconciled
was Thompson v. Utah, in which the Court had found that a
change in Utah law reducing the size of criminal juries from
12 to 8 persons violated the Ex Post Facto Clause by
depriving the defendant of “a substantial right involved in his
liberty.” 170 U.S. 343, 352–53 (1898). The Court overruled
Thompson in Collins, explaining that the reduced size of the
jury was not in fact an ex post facto violation because “[t]he
right to jury trial provided by the Sixth Amendment is
obviously a ‘substantial’ one, but it is not a right that has
anything to do with the definition of crimes, defenses, or
punishments, which is the concern of the Ex Post Facto
Clause.” Collins, 497 U.S. at 51.

     Similarly, in Cook v. United States, the Court held that an
act vesting jurisdiction over a crime in a newly formed
judicial district does not violate the Ex Post Facto Clause
because “[i]t only . . . subjects the accused to trial in th[e new]
district rather than in the court of some other judicial district
established by the government against whose laws the offense
was committed. This does not alter the situation of the
defendants in respect to their offense or its consequences.”
138 U.S. 157, 183 (1891); accord Gut v. Minnesota, 76 U.S.
                                31
35, 38 (1869) (“An ex post facto law does not involve, in any
of its definitions, a change of the place of trial of an alleged
offence after its commission.”); see also Duncan v. Missouri,
152 U.S. 377, 382–83 (1894) (suggesting no ex post facto
violation where defendant’s appeal was heard by smaller
appellate panel than provided for at time of his offense).

     It is therefore not a plain ex post facto violation to
transfer jurisdiction over a crime from an Article III court to a
military commission because such a transfer does not have
anything to do with the definition of the crime, the defenses or
the punishment. That is so regardless of the different
evidentiary rules that apply under the 2006 MCA. See
Carmell, 529 U.S. at 533 n.23 (change in “[o]rdinary rules of
evidence . . . do[es] not violate the [Ex Post Facto] Clause”);
id. at 542–47; Collins, 497 U.S. at 43 n.3; Beazell v. Ohio,
269 U.S. 167, 171 (1925); Thompson v. Missouri, 171 U.S.
380, 386–88 (1898); Hopt v. Utah, 110 U.S. 574, 589–90
(1884). Nor is this a case like Carmell, where a law
retroactively reduced the “quantum of evidence necessary to
sustain a conviction,” 529 U.S. at 530; the 2006 MCA
requires the Government to prove guilt beyond a reasonable
doubt, see 10 U.S.C. § 949l(c); see also Trial Tr. 233, 878
(military judge’s instructions to commission).11

    11
        Likewise, the greater maximum sentence provided in the
2006 MCA—the death penalty, as opposed to a maximum of life
imprisonment under section 2332(b)—does not present an ex post
facto problem. The Government did not seek the death penalty, see
Trial Tr. 958, and the military judge’s instructions to the
commission before sentencing specifically declared that “[t]he
maximum punishment that may be adjudged in this case is
confinement for life,” id. at 949. Further, the 2006 MCA requires a
12-member military commission if the death penalty is sought, see
10 U.S.C. § 949m(c), and Bahlul’s commission had only nine
members, see Trial Tr. 285. There was therefore no risk that the
                                32

     Our inquiry is not ended, however, because the 2006
MCA conspiracy-to-murder-protected-persons charge and
section 2332(b) do not have identical elements.           The
difference is a potential problem because the Ex Post Facto
Clause prohibits “retrospectively eliminating an element of
the offense” and thus “subvert[ing] the presumption of
innocence by reducing the number of elements [the
government] must prove to overcome that presumption.”
Carmell, 529 U.S. at 532. Both statutes require the existence
of a conspiracy and an overt act in furtherance thereof. See
18 U.S.C. § 2332(b)(2); 10 U.S.C. § 950v(b)(28) (2006); see
also Trial Tr. 846, 849–50 (military judge’s instructions to
commission). The 2006 MCA conspiracy charge is in one
sense more difficult to prove than section 2332(b) because it
applies only to alien unlawful enemy combatants engaged in
hostilities against the United States.       See 10 U.S.C.
§§ 948b(a), 948c, 948d; see also Trial Tr. 843–45
(instructions). But the 2006 MCA charge is in two ways
easier to prove than a section 2332(b) charge. It does not
require that the conspiracy occur “outside the United States”
or that the conspiracy be to kill a “national of the United
States,” as section 2332(b) does. It simply requires a
conspiracy to murder “one or more protected persons.” Trial
Tr. 850–51 (instructions); see supra n.10 (providing MCA’s
definition of “protected person”). Although the two statutes
are quite similar, then, the 2006 MCA conspiracy charge




greater sentence included in the 2006 MCA affected Bahlul’s
sentence. See Peugh, 133 S. Ct. at 2082 (“The touchstone of this
Court’s inquiry is whether a given change in law presents a
sufficient risk of increasing the measure of punishment attached to
the covered crimes.” (quotation marks omitted)).
                                33
eliminates two elements required to convict a defendant under
section 2332(b).12

     Nevertheless, Bahlul cannot bear his burden of
establishing that the elimination of the two elements
“seriously affect[ed] the fairness, integrity or public
reputation of judicial proceedings.” Olano, 507 U.S. at 732
(quotation marks omitted); see United States v. Vonn, 535
U.S. 55, 62–63 (2002) (defendant bears burden of proving
Olano’s fourth prong); see also United States v. Johnson, 331
F.3d 962, 967 (D.C. Cir. 2003) (proceeding directly to fourth
prong if it can resolve appeal). He cannot satisfy the fourth
prong because the charges against him and the commission’s
findings necessarily included those elements and the evidence
supporting them was undisputed. To explain why requires
that we first discuss the most on-point Supreme Court
precedent.

     In Johnson v. United States, the Supreme Court reviewed
a defendant’s conviction for perjury where the district court
had decided the issue of materiality itself rather than submit
that issue to the jury, as the Court’s precedent requires. 520
U.S. 461, 463 (1997). The defendant did not object, however,
so the Court reviewed his conviction for plain error. Because
the evidence of the missing materiality element was

    12
       To be clear, Bahlul was convicted of conspiracy as a stand-
alone offense that does not depend upon the completion of an
object offense. See Trial Tr. 848. He was not charged with
conspiracy as a theory of liability for a completed crime. See Trial
Tr. 109–12 (Government amended charge by striking allegation
that Bahlul joined “an enterprise of persons who share the common
criminal purpose that involved . . . the commission . . . of one or
more substantive offenses”); see also United States v. Ali, 718 F.3d
929, 941 (D.C. Cir. 2013) (noting difference between conspiracy as
stand-alone offense and conspiracy as theory of liability).
                                34
“overwhelming” and “essentially uncontroverted at trial,” the
Court concluded that the error, although plain, did not
seriously affect the fairness, integrity or public reputation of
judicial proceedings. Id. at 470; cf. Neder v. United States,
527 U.S. 1, 19 (1999) (failure to submit element to jury was
harmless error “where [the] defendant did not, and apparently
could not, bring forth facts contesting the omitted element”).
Similarly, in United States v. Cotton, the indictment failed to
charge the drug quantity involved in the offense, as the
Court’s precedent requires for any fact that enhances the
otherwise applicable statutory maximum sentence. 535 U.S.
625, 627–28 (2002). After the jury found the defendants
guilty of a narcotics conspiracy, the district court made drug
quantity findings that enhanced the defendants’ statutory
maximums. Id. at 628. This was “error” and it was “plain”
but the Court nevertheless upheld the convictions under
Olano’s fourth prong. Because the evidence of the requisite
drug quantity was “overwhelming” and “essentially
uncontroverted,” the Court concluded that “[t]he real threat
. . . to the fairness, integrity, and public reputation of judicial
proceedings would be if [the defendants] . . . were to receive a
sentence prescribed for those committing less substantial drug
offenses because of an error that was never objected to at
trial.” Id. at 633–34 (quotation marks omitted); accord
Johnson, 331 F.3d at 966–70; United States v. Webb, 255
F.3d 890, 899–902 (D.C. Cir. 2001).

    Here, the evidence of the two missing elements was not
simply “overwhelming” and “essentially uncontroverted”—it
was entirely uncontroverted. Bahlul was charged with
committing numerous overt acts “in Afghanistan, Pakistan
and elsewhere” that furthered the conspiracy’s unlawful
objects; those objects included the murder of protected
persons. App. 122–25. He did not dispute that his conduct
occurred outside the United States nor did he dispute that the
                               35
purpose of the conspiracy was to murder United States
nationals. See Trial Tr. 167 (Bahlul: “And what I did . . . is to
kill Americans . . . .”); id. at 511–12 (“[Bahlul] does not
consider anybody protected person[s] or civilians. . . . [A]s
long as you’re a[n] American, you are a target.”). Indeed,
several witnesses testified that Bahlul considered all
Americans to be targets. Id. at 503, 512, 596, 653. The
commission was instructed on the overt acts allegedly
undertaken by Bahlul in furtherance of the conspiracy, see id.
at 846–47, and was instructed that one of the conspiracy’s
object offenses was the murder of protected persons, id. at
850.      The commission specifically found that Bahlul
committed ten overt acts, all of which took place outside the
United States and several of which directly relate to the 9/11
attacks that killed thousands of United States nationals. App.
132–33. And it found that all seven of the alleged object
offenses, including murder of protected persons, were objects
of the conspiracy. App. 131. There is no scenario in which
the commission could have found that Bahlul committed these
overt acts yet rationally found that the conspiracy did not take
place outside the United States and did not have as an object
the murder of United States nationals. Accord Webb, 255
F.3d at 901. Although the commission was not specifically
instructed that it had to find these two elements, the overt acts
it did find Bahlul had committed necessarily included the two
elements and Bahlul did not, and does not, dispute either.
Therefore, although the 2006 MCA conspiracy offense, as
charged here, does “eliminat[e] an element of the offense,”
Carmell, 529 U.S. at 532, the omission did not seriously
affect the fairness, integrity, or public reputation of the
proceedings.
                               36
                           2. Section 821

     When Bahlul committed the crimes of which he was
convicted, section 821 granted—and still grants—military
commissions 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. Section 821 and its
predecessor statute have been on the books for nearly a
century. See Pub. L. No. 64-242, 39 Stat. 619, 653 (1916);
Pub. L. No. 66-242, 41 Stat. 759, 790 (1920); Pub. L. No. 81-
506, 64 Stat. 107, 115 (1950); Madsen v. Kinsella, 343 U.S.
341, 350–51 & n.17 (1952). We must therefore ascertain
whether conspiracy to commit war crimes was a “law of war”
offense triable by military commission under section 821
when Bahlul’s conduct occurred because, if so, Bahlul’s ex
post facto argument fails.

     In answering this question, we do not write on a clean
slate. In Hamdan, seven justices of the Supreme Court
debated the question at length. Four justices concluded that
conspiracy is not triable by military commission under section
821. 548 U.S. at 603–13 (plurality opinion of Stevens, J.).
Three justices opined that it is. Id. at 697–704 (Thomas, J.,
dissenting). Both opinions scoured relevant international and
domestic authorities but neither position garnered a majority.
The case was resolved on other grounds and the eighth vote—
one justice was recused—left the conspiracy question for
another day, noting that the Congress may “provide further
guidance in this area.” See id. at 655 (Kennedy, J.,
concurring). In light of the uncertainty left by the split, it was
not “plain” error to try Bahlul for conspiracy by military
commission pursuant to section 821. See United States v.
Terrell, 696 F.3d 1257, 1260 (D.C. Cir. 2012) (plain error met
only if “its erroneous character” is established by “a clear
precedent in the Supreme Court or this circuit”).
                               37

     The reason for the uncertainty is not only the divided
result in Hamdan but also the High Court’s failure to clearly
resolve a subsidiary question:        What body of law is
encompassed by section 821’s reference to the “law of war”?
That dispute takes center stage here. Bahlul contends that
“law of war” means the international law of war, full stop.
The Government contends that we must look not only to
international precedent but also “the common law of war
developed in U.S. military tribunals.” E.B. Br. of United
States 28; see also Oral Arg. Tr. 15 (“[W]e believe the law of
war is the international law of war as supplemented by the
experience and practice of our wars and our wartime
tribunals.”). The answer is critical because the Government
asserts that conspiracy is not an international law-of-war
offense. See E.B. Br. of United States 34; Oral Arg. Tr. 15.

     In Hamdan II, the Court said that “law of war” as used in
section 821 is a term of art that refers to the international law
of war. 696 F.3d at 1248; see also id. at 1252 (noting that
“U.S. precedents may inform the content of international
law”); cf. Kavanaugh Op. 11 n.5 (stating that Hamdan II’s
interpretation of section 821 “was not necessary to the
result”). Language in several Supreme Court opinions
supports that proposition. See, e.g., Quirin, 317 U.S. at 27–28
(“[T]his Court has recognized and applied the law of war as
including that part of the law of nations which prescribes, for
the conduct of war, the status, rights and duties of enemy
nations as well as of enemy individuals.”); id. at 29
(describing law of war as “branch of international law”); see
also Hamdan, 548 U.S. at 603 (plurality) (citing Quirin and
describing offense alleged therein as being “recognized as an
offense against the law of war” both “in this country and
internationally”); id. at 610–11 (analyzing international law
sources); id. at 641 (Kennedy, J., concurring) (“[T]he law of
                               38
war . . . is the body of international law governing armed
conflict.” (citing Quirin, 317 U.S. at 28)); Madsen, 343 U.S.
at 354–55 (“The ‘law of war’ . . . includes at least that part of
the law of nations which defines the powers and duties of
belligerent powers occupying enemy territory pending the
establishment of civil government.”); Yamashita, 327 U.S. at
12–16 (analyzing international precedent in determining
whether offense was violation of law of war); Rogers Op. 6–7
(concluding on de novo review that section 821 refers to
international law of war).         Several Executive Branch
interpretations and scholarly articles also support that reading.
See Hamdan II, 696 F.3d at 1248–49 & n.9 (collecting
citations).

     On the other hand, section 821 might not be so limited
(as two of our colleagues would hold on de novo review). See
Brown Op. 3; Kavanaugh Op. 7–11; see also Hamdan, 548
U.S. at 689 (Thomas, J., dissenting) (“[W]hether an offense is
a violation of the law of war cognizable before a military
commission must be determined pursuant to the system of
common law applied by military tribunals . . . [which] is
derived from the experience of our wars and our wartime
tribunals and the laws and usages of war as understood and
practiced by the civilized nations of the world.” (citations and
quotation marks omitted)). Significantly, both the Hamdan
plurality and dissent relied primarily on domestic precedent to
ascertain whether conspiracy could be tried under section 821.
See Hamdan, 548 U.S. at 603–09 (plurality); id. at 689–704
(Thomas, J., dissenting).13      There is also language in
Yamashita and Quirin that domestic precedent is an important

    13
         The Hamdan plurality did not expressly decide whether
section 821’s reference to the “law of war” is limited to the
international law of war. See Hamdan, 548 U.S. at 604–13
(plurality).
                               39
part of our inquiry. See Yamashita, 327 U.S. at 8 (“[The
Congress] adopted the system of military common law
applied by military tribunals so far as it should be recognized
and deemed applicable by the courts, and as further defined
and supplemented by the Hague Convention . . . .”); Quirin,
317 U.S. at 31–35, 42 n.14 (evaluating domestic precedent to
determine whether offense charged was law-of-war offense);
see also Madsen, 343 U.S. at 347–48. Moreover, as the
Supreme Court has explained, when the Congress enacted
section 821 and its predecessors, it intended to preserve, not
limit, the pre-existing jurisdiction of military commissions.
See Madsen, 343 U.S. at 352–53; Yamashita, 327 U.S. at 19–
20; see also Hamdan, 548 U.S. at 593 (majority) (“[T]he
Quirin Court recognized that Congress had simply preserved
what power, under the Constitution and the common 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.”).
It is therefore arguable that the Congress also intended to
incorporate military commission precedents predating section
821’s enactment. See Sekhar v. United States, 133 S. Ct.
2720, 2724 (2013) (“[I]f a word is obviously transplanted
from another legal source, whether the common law or other
legislation, it brings the old soil with it.” (quoting Felix
Frankfurter, Some Reflections on the Reading of Statutes, 47
COLUM. L. REV. 527, 537 (1947))); Lorillard v. Pons, 434
U.S. 575, 581 (1978) (“[W]here, as here, Congress adopts a
new law incorporating sections of a prior law, Congress
normally can be presumed to have had knowledge of the
interpretation given to the incorporated law, at least insofar as
it affects the new statute.”).

    Ultimately, we need not resolve de novo whether section
821 is limited to the international law of war. It is sufficient
for our purpose to say that, at the time of this appeal, the
                               40
answer to that question is not “obvious.” Olano, 507 U.S. at
734; see Henderson v. United States, 133 S. Ct. 1121, 1130–
31 (2013) (plainness of error determined at time of appeal).
As seven justices did in Hamdan, we look to domestic
wartime precedent to determine whether conspiracy has been
traditionally triable by military commission. That precedent
provides sufficient historical pedigree to sustain Bahlul’s
conviction on plain-error review.

     Most notably, the individuals responsible for the
assassination of President Abraham Lincoln were charged
with a single offense—“combining, confederating, and
conspiring . . . to kill and murder . . . Abraham Lincoln”—and
were convicted of that offense by military commission.
General Court-Martial Order No. 356, War Dep’t (July 5,
1865), reprinted in H.R. DOC. NO. 55-314, at 696 (1899).14
The specification of the offense includes several paragraphs,
each of which sets forth a separate overt act done “in further
prosecution of the unlawful and traitorous conspiracy.” Id. at
697–98; see also THE ASSASSINATION OF PRESIDENT LINCOLN
AND THE TRIAL OF THE CONSPIRATORS 18–21 (New York,
Moore, Wilstach & Baldwin 1865). A federal district court
later denied three of the conspirators’ habeas petitions raising
jurisdictional objections to the commission. Ex Parte Mudd,
17 F. Cas. 954 (S.D. Fla. 1868).

     President Andrew Johnson personally approved the
convictions. In doing so, he considered the jurisdictional
limits of military commissions: He asked Attorney General
James Speed whether the accused could be tried for
    14
         The Hamdan plurality interpreted this precedent as
convicting the conspirators only of the completed offense of
assassination, not inchoate conspiracy. Hamdan, 548 U.S. at 604
n.35 (plurality). But see id. at 699 n.12 (Thomas, J., dissenting)
(finding it clear that inchoate conspiracy was tried).
                                 41
conspiracy in a military commission. In a lengthy opinion,
Attorney General Speed said they could. See Military
Commissions, 11 Op. Att’y Gen. 297 (1865). We think this
highest-level Executive Branch deliberation is worthy of
respect in construing the law of war. Cf. Sosa v. Alvarez-
Machain, 542 U.S. 692, 733–34 (2004) (looking “albeit
cautiously” to sources like “controlling executive . . . act[s]”
to ascertain current state of international law (quoting The
Paquete Habana, 175 U.S. 677, 700 (1900)); Tel-Oren v.
Libyan Arab Republic, 726 F.2d 774, 780 n.6 (D.C. Cir. 1984)
(Edwards, J., concurring) (Attorney General opinions not
binding but “entitled to some deference, especially where
judicial decisions construing a statute are lacking”). Granted,
the Attorney General’s framing of the question presented—
“whether the persons charged with the offence of having
assassinated the President can be tried before a military
tribunal”—casts some doubt on whether he was addressing
inchoate conspiracy or the offense of assassination. 11 Op.
Att’y Gen. at 297; see Hamdan, 548 U.S. at 604 n.35
(plurality). But the Attorney General’s opinion was written
after the commission had been convened and the convictions
had been approved; he would therefore have been aware that
the sole offense alleged was conspiracy.15 On the other hand,

    15
        Some doubt about the precise nature of the charge also
appears in the transcript of the conspirators’ trial. Thomas Ewing,
counsel for several of the defendants, objected to the ambiguity of
the charge, stating that “[t]here is but one charge, in form, against
the accused; but, in fact, there seem to be four charges, each
alleging the commission of a separate and distinct offense.” THE
ASSASSINATION OF PRESIDENT LINCOLN AND THE TRIAL OF THE
CONSPIRATORS, supra, at 244. He listed what he perceived to be
the four offenses charged: conspiracy, traitorously murdering
President Lincoln, traitorously assaulting with intent to kill
Secretary of State William Seward and lying in wait with intent to
traitorously murder then-Vice President Johnson. Id. at 244–45.
                                   42
that the Attorney General’s opinion was written after the
convictions were approved may undermine its persuasive
value, as it could be viewed as a post hoc rationalization for a
decision already made.

     Either way, the Lincoln conspirators’ trial was a matter of
paramount national importance and attracted intense public
scrutiny. Thus, when the Congress enacted section 821’s
predecessor—and “preserved what power, under the
Constitution and the common law of war, the President had
had before 1916 to convene military commissions,” Hamdan,
548 U.S. at 593 (majority)—it was no doubt familiar with at
least one high-profile example of a conspiracy charge tried by
a military commission. Because of the national prominence
of the case and the highest-level Executive Branch
involvement, we view the Lincoln conspirators’ trial as a
particularly significant precedent.16

The Judge Advocate responded that “[t]he general allegation is a
conspiracy” and that “[t]he pleadings proceed, after averring this
conspiracy, . . . to set forth clearly and specifically the part which it
is believed and alleged each one of them took in the execution of
that conspiracy.” Id. at 245; see also id. at 246–47 (further
discussion of the charge).
     16
        William Winthrop—the Blackstone of military law—also
concluded that conspiracy is an offense that is “both a crime against
society and a violation of the laws of war.” WINTHROP, MILITARY
LAW AND PRECEDENTS, supra, at 842; accord WILLIAM
WINTHROP, A DIGEST OF OPINIONS OF THE JUDGE ADVOCATE
GENERAL OF THE ARMY 328–29 (1880) (“[c]onspiracy by two or
more to violate the laws of war by destroying life or property in aid
of the enemy” is an “offence[] against the laws and usages of war”).
That said, although Winthrop based that conclusion in part on the
Lincoln conspirators’ case, he also relied on Civil War-era field
orders. WINTHROP, MILITARY LAW AND PRECEDENTS, supra, at
839 & n.5 (explaining different bases of military jurisdiction and
                               43

     Also noteworthy is the World War II-era military
commission trial of several Nazi saboteurs who entered the
United States intending to destroy industrial facilities; they
were convicted of, inter alia, conspiracy to commit violations
of the law of war. See Quirin, 317 U.S. at 21–23. Although
the Supreme Court resolved the case on other grounds and
therefore did not review the validity of the conspiracy
conviction, the case remains another prominent example of a
conspiracy charge tried in a law-of-war military commission.
President Franklin D. Roosevelt, like President Johnson
before him, approved the charges. See 7 Fed. Reg. 5103-02
(July 7, 1942). Moreover, Quirin is not the sole example
from that era. See Colepaugh v. Looney, 235 F.2d 429, 431–
32 (10th Cir. 1956) (upholding conviction by military
commission of Nazi saboteur of conspiracy to commit offense
against law of war); General Order (G.O.) No. 52, War Dep’t
(July 7, 1945) (President Truman approves convictions of
Colepaugh conspirators), reprinted in Supp. Auth. 149–50;
Memo. of Law from Tom C. Clark, Assistant Att’y Gen., to
Major General Myron C. Kramer, Judge Advocate Gen., at 6
(Mar. 12, 1945), reprinted in Supp. Auth. 139 (opining, with
regard to Colepaugh case, that “it may be said to be well
established that a conspiracy to commit an offense against the
laws of war is itself an offense cognizable by a commission
administering military justice”). Finally, during the Korean
War, General Douglas MacArthur ordered that persons
accused of “conspiracies and agreements to commit . . .
violations of the laws and customs of war of general

citing cases of Henry Wirz, William Murphy, G. St. Leger Grenfel
and others as examples of criminal conspiracies tried by military
commission on combination of jurisdictional bases). The field
orders lack the high-level Executive Branch consultation of the
Lincoln conspirators’ case, however, and give us pause for
additional reasons discussed infra p. 46.
                                 44
application” be tried by military commission. See Letter
Order, Gen. HQ, United Nations Command, Tokyo, Japan,
Trial of Accused War Criminals (Oct. 28, 1950) (Rules of
Criminal Procedure for Military Commissions, Rule 4).

     We do not hold that these precedents conclusively
establish conspiracy as an offense triable by military
commission under section 821. After all, four justices
examined the same precedents and found them insufficiently
clear. Hamdan, 548 U.S. at 603–09 (plurality);17 cf. Marks v.
United States, 430 U.S. 188, 193 (1977). But there are two
differences between Hamdan and this case. First, the
elements of the conspiracy charge were not defined by statute
in Hamdan and therefore the plurality sought precedent that
was “plain and unambiguous.” 548 U.S. at 602. Here, the
Congress has positively identified conspiracy as a war crime.
We need not decide the effect of the Congress’s action,
however, because we rely on the second difference: The
Hamdan plurality’s review was de novo; our review is for
plain error. We think the historical practice of our wartime
tribunals is sufficient to make it not “obvious” that conspiracy
was not traditionally triable by law-of-war military
commission under section 821. Olano, 507 U.S. at 734. We
therefore conclude that any Ex Post Facto Clause error in
trying Bahlul on conspiracy to commit war crimes is not
plain. See United States v. Vizcaino, 202 F.3d 345, 348 (D.C.
Cir. 2000) (assuming error to decide it was not plain).


    17
         The Hamdan plurality thought Quirin suggested “that
conspiracy is not a violation of the law of war” because the Court’s
“analysis . . . placed special emphasis on the completion of [another
charged] 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 commission—without the actual commission of . . . a
‘hostile and warlike act.’ ” 548 U.S. at 606–07 (plurality).
                                  45
                       B. Material Support

     A different result obtains, however, regarding Bahlul’s
conviction of providing material support for terrorism.18 The
Government concedes that material support is not an
international law-of-war offense, see Oral Arg. Tr. 15; Panel
Br. of United States 50, 57, and we so held in Hamdan II, 696
F.3d at 1249–53. But, in contrast to conspiracy, the
Government offers little domestic precedent to support the
notion that material support or a sufficiently analogous
offense has historically been triable by military commission.
Although Bahlul carries the burden to establish plain error,
see United States v. Brown, 508 F.3d 1066, 1071 (D.C. Cir.
2007), we presume that in the unique context of the “domestic
common law of war”—wherein the Executive Branch shapes
the relevant precedent and individuals in its employ serve as
prosecutor, judge and jury—the Government can be expected
to direct us to the strongest historical precedents. What the
Government puts forth is inadequate.



     18
         The 2006 MCA provides: “Any person subject to this
chapter who provides material support or resources, knowing or
intending that they are to be used in preparation for, or in carrying
out, an act of terrorism . . . , or who intentionally provides material
support or resources to an international terrorist organization
engaged in hostilities against the United States, knowing that such
organization has engaged or engages in terrorism . . . , shall be
punished . . . .” 10 U.S.C. § 950v(b)(25). The provision cross-
references the Act’s prohibition of “terrorism,” which is defined as
an act that “kills or inflicts great bodily harm on one or more
protected persons, or . . . that evinces a wanton disregard for human
life, in a manner calculated to influence or affect the conduct of
government or civilian population by intimidation or coercion, or to
retaliate against government conduct.” Id. § 950v(b)(24).
                               46
     The Government relies solely on a number of Civil War-
era field orders approving military commission convictions of
various offenses that, the Government contends, are
analogous to material support. Before delving into the
specifics of the orders, we note our skepticism that such
informal field precedent can serve as the sole basis for
concluding that a particular offense is triable by a law-of-war
military commission. Unlike the Lincoln conspirators’ and
Nazi saboteurs’ cases, which attracted national attention and
reflected the deliberations of highest-level Executive Branch
officials, the field precedents are terse recordings of
drumhead justice executed on or near the battlefield. Indeed,
several precedents cited by the Government for trying
material support and solicitation under the “law of war” were
issued by the same 1862 military commission that tried one
Henry Willing for the offense of “[b]eing a bad and dangerous
man.” G.O. No. 19, HQ, Dep’t of the Mississippi (Apr. 24,
1862), 1 THE WAR OF THE REBELLION, OFFICIAL RECORDS OF
THE UNION AND CONFEDERATE ARMIES (OR) ser. II, at 480–
81. In addition, the military commissions these orders
memorialize were not always models of due process.19 And,
as the Hamdan plurality explained, the Civil War
commissions “operated as both martial law or military
government tribunals and law-of-war commissions,” obliging
us to treat the precedents “with caution” because of their
unclear jurisdictional basis. 548 U.S. at 596 n.27 (plurality);
see also id. at 608.20

    19
       See Frank J. Williams & Nicole J. Benjamin, Military Trials
of Terrorists: From the Lincoln Conspirators to the Guantanamo
Inmates, 39 N. KY. L. REV. 609, 625 (2012); David Glazier,
Precedents Lost: The Neglected History of the Military
Commission, 46 VA. J. INT’L L. 5, 39–40 (2005).
    20
        See also Hamdan, 548 U.S. at 602 n.34 (plurality)
(explaining that because of “vagueness” concerns, “caution . . .
                               47

     In any event, even if the law of war can be derived from
field precedents alone, none of the cited orders charges the
precise offense alleged here—providing material support for
terrorism. The Government nonetheless contends that the
material support charge “prohibits the same conduct, under a
modern label, as the traditional offense of joining with or
providing aid to guerrillas and other unlawful belligerents.”
E.B. Br. of United States 48. But we do not think the cited
field orders establish that such conduct was tried by law-of-
war military commissions during the Civil War.21

     First, every precedent cited by the Government involves
offenses committed in Missouri, a border state; none is from a
state that seceded. See Dow v. Johnson, 100 U.S. 158, 164–
65 (1879) (observing that, during the Civil War, “[t]he people
of the loyal States . . . and the people of the Confederate
States . . . became enemies to each other, and . . .
[c]ommercial intercourse and correspondence between them
were prohibited . . . by the accepted doctrines of public law”);
McKinzie v. Hill, 51 Mo. 303, 307 (1873) (“[T]he principles
[regarding the duty of “total non-intercourse between the
belligerents”] have no application to the present case.
Missouri was not one of the States that joined in the
rebellion.”). The difference between a border state—whose
citizens owed a duty of loyalty to the United States—and a
state that seceded—whose citizens did not—is significant.
The crime of “aiding the enemy,” which includes as an
element the breach of a duty of loyalty owed to the United
States, had long been triable by military commission. See

must be exercised in the incremental development of common-law
crimes”); Hamdan II, 696 F.3d at 1250 n.10 (similar).
    21
       In reviewing this Civil War precedent, we hold only that it
does not sanction trying material support by military commission.
                               48
Hamdan II, 696 F.3d at 1245 n.4 (citing Hamdan, 548 U.S. at
600–01 n.32 (plurality)); WINTHROP, MILITARY LAW AND
PRECEDENTS, supra, at 839–40 (“offences in violation of the
laws and usages of war” subject to trial by law-of-war
military commission include “breaches of the law of non-
intercourse with the enemy, such as . . . furnishing them with
money, arms, provisions, medicines, &c”); see also 10 U.S.C.
§ 950v(b)(26) (2006) (codifying offense of aiding enemy to
include element of “breach of an allegiance or duty to the
United States”). The orders cited by the Government
frequently refer to the treasonous nature of the conduct,
implying a breach of loyalty. See, e.g., G.O. No. 9, HQ,
Dep’t of the Mississippi (Mar. 25, 1862), 1 OR ser. II, at 465–
66 (case of John Montgomery); id. at 467 (case of Joseph
Bollinger); G.O. No. 1, HQ, Dep’t of the Missouri (Jan. 1,
1862), 1 OR ser. II, at 248 (“[C]ertain acts of a treasonable
character such as conveying information to the enemy, acting
as spies, &c., are military offenses triable by military tribunals
and punishable by military authority.”); see also Young v.
United States, 97 U.S. 39, 62 (1877) (“[T]reason is a breach
of allegiance, and can be committed by him only who owes
allegiance . . . .” (quotation marks omitted)). The material
support offense charged here, which lacks a breach of loyalty
requirement, is plainly distinguishable from the “aiding the
enemy” precedent.

     Second, several of the cited field orders appear to involve
offenses more akin to aiding and abetting a law-of-war
violation. See, e.g., G.O. No. 19, HQ, Dep’t of the
Mississippi (Apr. 24, 1862), 1 OR ser. II, at 478 (Matthew
Thompson convicted of “joining with, aiding and assisting [a]
band [of desperadoes] in the commission of acts of plunder,
robbery and abuse of the citizens of the State of Missouri”).
Aiding and abetting is a theory of criminal liability, not a
stand-alone offense like material support. See Ali, 718 F.3d at
                               49
936. As the Court said in Hamdan II, “aiding and abetting
terrorism prohibits different conduct, imposes different mens
rea requirements, and entails different causation standards
than material support for terrorism.” 696 F.3d at 1252. Thus,
“[i]f the Government wanted to charge [Bahlul] with aiding
and abetting terrorism . . . it should have done so.” Id.; see 10
U.S.C. § 950q(1) (2006) (one who “aids [or] abets” offense
proscribed by 2006 MCA is punishable as principal).

     Third, other orders appear to involve the offense of
unlawful belligerency—that is, directly waging guerrilla
warfare. See, e.g., G.O. No. 15, HQ, Dep’t of the Mississippi
(Apr. 3, 1862), 1 OR ser. II, at 472–476 (approving
convictions of several men who each, not “being a soldier
belonging to any lawfully authorized and organized military
forces at war with the United States,” “t[ook] up arms as an
insurgent and commit[ted] acts of hostility against” United
States military forces); G.O. No. 9, HQ, Dep’t of the
Mississippi (Mar. 25, 1862), 1 OR ser. II, at 464–65 (William
Kirk convicted of “belong[ing] to a marauding or guerrilla
band” that “did unlawfully plunder and take away a certain
yoke of oxen, wagon and other property”); see also
Instructions for the Government of Armies of the United
States in the Field, G.O. No. 100, art. 82 (Apr. 24, 1863);
WINTHROP, MILITARY LAW AND PRECEDENTS, supra, at 840.

     The upshot is that the Civil War field precedent is too
distinguishable and imprecise to provide the sole basis for
concluding that providing material support for terrorism was
triable by law-of-war military commission at the time of
Bahlul’s conduct.22 We therefore think it was a plain ex post

    22
      Even the Government is dubious of its argument: Executive
Branch officials previously acknowledged in prepared
congressional testimony that “there are serious questions as to
                                50
facto violation—again, assuming without deciding that the
protection of the Ex Post Facto Clause extends to Bahlul, see
supra pp. 26–27—to try Bahlul by military commission for
that new offense. See Collins, 497 U.S. at 42–43. The error
is prejudicial and we exercise our discretion to correct it by
vacating Bahlul’s material support conviction. Olano, 507
U.S. at 734–36; see also Casey, 343 U.S. at 808 (vacating
conviction based on Government’s confession of error);
United States v. Law, 528 F.3d 888, 909 (D.C. Cir. 2008)
(same); cf. Petite, 361 U.S. at 531 (vacating conviction based
on Government’s motion).23


whether material support for terrorism or terrorist groups is a
traditional violation of the law of war.” Legal Issues Regarding
Military Commissions and the Trial of Detainees for Violations of
the Law of War: Hearing Before the S. Comm. on Armed Services,
111th Cong. 12 (2009) (statement of David Kris, Assistant Attorney
General, National Security Division, Department of Justice); see
also id. at 9 (statement of Jeh Johnson, General Counsel,
Department of Defense) (“After careful study, the administration
has concluded that appellate courts may find that ‘material support
for terrorism’—an offense that is also found in Title 18—is not a
traditional violation of the law of war.”).
    23
        Unlike with conspiracy, the Government has not identified a
pre-existing federal criminal statute that might cure any ex post
facto aspect of Bahlul’s material support conviction.          The
Government cites 18 U.S.C. § 2339A, which criminalizes providing
material support or resources knowing they are to be used in a
violation of section 2332, but that offense was not made
extraterritorial until October 26, 2001. See Pub. L. No. 107-56,
§ 805(a)(1)(A), 115 Stat. 272, 377. Although Bahlul was not
captured until December 2001, nearly all of the conduct of which
he was convicted took place before September 11, 2001. The only
overt act that necessarily occurred after September 11 was Bahlul’s
research on the economic effects of the attack. The record does not
reflect, however, whether Bahlul committed that or any other act of
                                51

                         C. Solicitation

     We also conclude that solicitation of others to commit
war crimes is plainly not an offense traditionally triable by
military commission.24 The Government concedes it is not an
international law-of-war offense. See Oral Arg. Tr. 15; Panel
Br. of United States 50, 57. The Government contends that
solicitation “possesses a venerable lineage as an offense
triable by military commission,” E.B. Br. of United States 50,
but it cites only two Civil War-era field orders involving three
defendants in support thereof. It mischaracterizes one of the
orders, asserting that “a military commission convicted
Francis Skinner of ‘counsel[ing]’ and ‘invit[ing]’ others to
destroy a railroad in violation of the law of war,” id., when in
fact Skinner was acquitted of that offense. See G.O. No. 19,
HQ, Dep’t of the Mississippi (Apr. 24, 1862), 1 OR ser. II, at
476–77. And although the other two defendants in the cited
cases were convicted on charges that resemble the 2006 MCA
solicitation offense, they were also convicted of personal
involvement in the crimes they solicited. See id. at 478
(James Barnes convicted of both “attack[ing] the dwelling-
house of one Thomas H. Keene . . . and with guns and pistols
attempt[ing] to murder the occupants of said house” and
“incit[ing] certain persons unknown to make” that attack);
G.O. No. 15, HQ, Dep’t of the Mississippi (Apr. 3, 1862), 1

material support constituting a violation of section 2339A after
October 26, 2001. This charge, then, is unlike the conspiracy
charge, where Bahlul expressly conceded and the jury necessarily
found the two omitted elements.
    24
        The 2006 MCA provides: “Any person subject to this
chapter who solicits or advises another or others to commit one or
more substantive offenses triable by military commission under this
chapter shall . . . be punished . . . .” 10 U.S.C. § 950u.
                                52
OR ser. II, at 475 (Edward Wingfield convicted of both
“assist[ing] and abet[ting] the said persons in the destruction
of the track, bridges and buildings of the [North Missouri
Railroad]” and “incit[ing], induc[ing] and procur[ing] the said
persons to take up arms and to commit acts of hostility against
the property of the United States”); cf. Hamdan, 548 U.S. at
609 (plurality).

     As noted, we are skeptical that field orders can be the
sole basis for military commission jurisdiction over a
particular offense. See supra p. 46. Moreover, the two field
orders discussed fall far short of meeting any showing we
would require. Because solicitation to commit war crimes
was not an offense triable by law-of-war military commission
when Bahlul’s conduct occurred, it is a plain ex post facto
violation—again, assuming without deciding that the
protection of the Ex Post Facto Clause extends to Bahlul, see
supra pp. 26–27—to try him by military commission for that
new offense. See Collins, 497 U.S. at 42–43. The error is
prejudicial and we exercise our discretion to correct it by
vacating Bahlul’s solicitation conviction. Olano, 507 U.S. at
734–736; see also Casey, 343 U.S. at 808; Law, 528 F.3d at
909; cf. Petite, 361 U.S. at 531.25


    25
         As with material support, we cannot conclude that a pre-
existing federal statute might cure any ex post facto aspect of
Bahlul’s solicitation conviction. The Government notes that, when
Bahlul’s conduct occurred, 18 U.S.C. § 373 criminalized
solicitation of another person to “engage in conduct constituting a
felony that has as an element the use, attempted use, or threatened
use of physical force against property or against the person of
another.” The Government’s brief does not identify an offense that
Bahlul solicited, however, which it must do for us to compare the
elements of a pre-existing criminal offense with the elements of the
charge under the MCA.
                              53
                     V. Remaining Issues
     In his brief to the panel, Bahlul raised four challenges to
his convictions that we have not addressed here. He argued
that (1) the Congress exceeded its Article I, § 8 authority by
defining crimes triable by military commission that are not
offenses under the international law of war, see Br. for Bahlul
38, Bahlul v. United States, No. 11-1324 (D.C. Cir. Mar. 9,
2012); (2) the Congress violated Article III by vesting
military commissions with jurisdiction to try crimes that are
not offenses under the international law of war, see id. at 39–
40; (3) his convictions violate the First Amendment, see id. at
43; and (4) the 2006 MCA discriminates against aliens in
violation of the equal protection component of the Due
Process Clause, see id. at 54. We intended neither the en
banc briefing nor argument to address these four issues. See
Order, Bahlul v. United States, No. 11-1324 (D.C. Cir. May 2,
2013) (notifying parties that Equal Protection and First
Amendment issues are not “within the scope of the rehearing
en banc”). And with the exception of a few passages
regarding the first two, we received none from the parties.
We therefore remand the case to the original panel of this
Court to dispose of Bahlul’s remaining challenges to his
conspiracy conviction. See United States v. McCoy, 313 F.3d
561, 562 (D.C. Cir. 2002) (en banc) (remanding outstanding
issue to panel).
     For the foregoing reasons, we reject Bahlul’s ex post
facto challenge to his conspiracy conviction and remand that
conviction to the panel to consider his alternative challenges
thereto. In addition, we vacate Bahlul’s convictions of
providing material support for terrorism and solicitation of
others to commit war crimes, and, after panel consideration,
remand to the CMCR to determine the effect, if any, of the
two vacaturs on sentencing.
                                                   So ordered.
    KAREN LECRAFT HENDERSON, Circuit Judge, concurring:
I write separately to emphasize, for me, the critical nature of
the Government’s concession that the Ex Post Facto Clause
protects Bahlul. Had the Government not conceded the point
and the Court not decided to act on the concession, cf. Young
v. United States, 315 U.S. 257, 258–59 (1942), I would have
reached a different conclusion. I briefly explain why.

        I. It Is Not “Plain” That the Ex Post Facto Clause
                        Protects Bahlul

      “ ‘Plain’ is synonymous with ‘clear’ or, equivalently,
‘obvious.’ ” United States v. Olano, 507 U.S. 725, 734
(1993). Put another way, “the error must be ‘so plain the trial
judge and prosecutor were derelict in countenancing it, even
absent the defendant’s timely assistance in detecting it.’ ”
United States v. Saro, 24 F.3d 283, 286 (D.C. Cir. 1994)
(quoting United States v. Frady, 456 U.S. 152, 163 (1982)).
An error meets this high standard only if “its erroneous
character” is established by “a clear precedent in the Supreme
Court or this circuit.” United States v. Terrell, 696 F.3d 1257,
1260 (D.C. Cir. 2012). Indeed, “[r]arely do we find an error
to be plain where ‘this court has not ruled on the question.’ ”
United States v. Laureys, 653 F.3d 27, 32–33 (D.C. Cir. 2011)
(per curiam) (quoting United States v. Thomas, 896 F.2d 589,
591 (D.C. Cir. 1990)); see also United States v. Merlos, 8
F.3d 48, 51 (D.C. Cir. 1993) (error may be plain even in
absence of controlling precedent if trial court failed to follow
“legal norm[ that is] absolutely clear (for example, because of
the clarity of a statutory provision or court rule)”). To be
“plain,” the error must be clear or obvious at the time of
appeal. Henderson v. United States, 133 S. Ct. 1121, 1130–
31 (2013); United States v. Miller, 738 F.3d 361, 372 (D.C.
Cir. 2013).

    Bahlul contends that his convictions are unconstitutional
because the 2006 MCA, as applied to him, is an ex post facto
                                2
law. Even assuming that Bahlul is correct, the error is not
plain because there is no holding by any court that an
unlawful alien enemy combatant detained abroad is entitled to
the protections of the Ex Post Facto Clause. Before
Boumediene, Johnson v. Eisentrager, 339 U.S. 763 (1950),
and United States v. Verdugo-Urquidez, 494 U.S. 259 (1990),
“were thought to be the controlling Supreme Court cases on
the Constitution’s application to aliens abroad.” Rasul v.
Myers, 563 F.3d 527, 531 (D.C. Cir. 2009) (per curiam). In
Eisentrager, the Supreme Court held that the Fifth
Amendment did not apply to aliens with neither property nor
presence in the United States. 339 U.S. at 784. Verdugo-
Urquidez, relying on Eisentrager, held that the Fourth
Amendment did not apply to such aliens. 494 U.S. at 269,
273–75. Other Supreme Court opinions similarly suggested
that the Constitution did not apply outside the sovereign
United States. Zadyvas v. Davis, 533 U.S. 678, 693 (2001);
Kwong Hai Chew v. Colding, 344 U.S. 590, 597 n.5 (1953);
United States v. Belmont, 301 U.S. 324, 332 (1937); United
States v. Curtiss-Wright Export Corp., 299 U.S. 304, 318
(1936). We have followed those precedents consistently,
recognizing that the Fifth Amendment did not extend beyond
the boundaries of the United States. See, e.g., Jifry v. FAA,
370 F.3d 1174, 1182–83 (D.C. Cir. 2004); 32 Cnty.
Sovereignty Comm. v. Dep’t of State, 292 F.3d 797, 799 (D.C.
Cir. 2002); Harbury v. Deutch, 233 F.3d 596, 603–04 (D.C.
Cir. 2000), rev’d on other grounds sub nom. Christopher v.
Harbury, 536 U.S. 403 (2002); People’s Mojahedin Org. of
Iran v. U.S. Dep’t of State, 182 F.3d 17, 22 (D.C. Cir. 1999).

     In Boumediene, the Supreme Court for the first time in
our history extended a constitutional protection to an alien
located outside the sovereign territory of the United States.
553 U.S. at 770. But the Supreme Court “explicitly confined
its constitutional holding ‘only’ to the extraterritorial reach of
                               3
the Suspension Clause” and “disclaimed any intention to
disturb existing law governing the extraterritorial reach of any
constitutional provisions, other than the Suspension Clause.”
Rasul, 563 F.3d at 529 (quoting Boumediene, 553 U.S. at
795). Indeed, it remains the law of this circuit that, after
Boumediene, aliens detained at Guantanamo may not invoke
the protections of the Due Process Clause of the Fifth
Amendment. See Kiyemba v. Obama, 555 F.3d 1022, 1026 &
n.9 (D.C. Cir. 2009) (“due process clause does not apply to
aliens without property or presence in the sovereign territory
of the United States” and Guantanamo “is not part of the
sovereign territory of the United States”), vacated and
remanded, 559 U.S. 131 (2010), reinstated in relevant part,
605 F.3d 1046 (D.C. Cir. 2010), cert. denied, 131 S. Ct. 1631
(2011); see also Al-Madhwani v. Obama, 642 F.3d 1071,
1077 (D.C. Cir. 2011); Kiyemba v. Obama, 561 F.3d 509, 518
n.4 (D.C. Cir. 2009) (Kavanaugh, J., concurring); Cuban Am.
Bar Ass’n, Inc. v. Christopher, 43 F.3d 1412, 1428 (11th Cir.
1995) (Fifth Amendment does not apply to Cubans and
Haitians temporarily housed at Guantanamo). Whether
Boumediene in fact portends a sea change in the
extraterritorial application of the Constitution writ large, we
are bound to take the Supreme Court at its word when it limits
its holding to the Suspension Clause. See Rodriguez de
Quijas v. Shearson/Am. Express, Inc., 490 U.S. 477, 480–81
(1989). Thus, the extraterritorial inapplicability of the Ex
Post Facto Clause remains as it was before Boumediene.

     Bahlul points to no case from the Supreme Court or any
court of appeals, nor to any other “absolutely clear” legal
norm, opining that the Ex Post Facto Clause applies beyond
the sovereign territory of the United States. Finding such a
precedent would be a remarkable feat inasmuch as
Boumediene expressly recognized that it was the first case to
apply any constitutional provision to aliens located beyond
                                4
our sovereign territory: “It is true that before today the Court
has never held that noncitizens detained by our Government
in territory over which another country maintains de jure
sovereignty have any rights under our Constitution.” 553
U.S. at 770. Because there is no clear precedent establishing
that the Ex Post Facto Clause applies to aliens held at
Guantanamo, prosecuting Bahlul under the 2006 MCA cannot
constitute plain constitutional error.

    II. The Ex Post Facto Clause Does Not Protect Bahlul

     Even if our review were de novo, I would conclude that
the Ex Post Facto Clause does not apply to aliens detained at
Guantanamo. As discussed above, only one constitutional
protection applies to Guantanamo even after Boumediene.
553 U.S. at 795 (“Our decision today holds only that
petitioners before us are entitled to seek the writ.”); see Rasul,
563 F.3d at 529. Boumediene is the law and therefore it must
be followed. But before 2008, the Constitution did not apply
to aliens without property or presence in the United States.
After 2008, the Suspension Clause—and only the Suspension
Clause—protects only those aliens detained on the
southeastern tip of an island outside the sovereign United
States.    We have previously said that, “[a]s a novel
constitutional development, we are loath to expand
Boumediene’s reach without specific guidance from the
Supreme Court, particularly where expansion would carry us
further into the realm of war and foreign policy.” Maqaleh v.
Hagel, 738 F.3d 312, 336 n.16 (D.C. Cir. 2013). I see no
reason to abandon that caution.

     Finally, we must remember the who, what and where of
this case. Bahlul is an alien unlawful enemy combatant
who—like Hitler’s Goebbels—led Osama bin Laden’s
propaganda operation and freely admitted his role in the 9/11
                                 5
atrocities. He was tried outside the sovereign United States
for war crimes. During the post-World War II Nuremberg
trials several defendants raised ex post facto objections but
they were rejected as “sheer absurdity” under international
law. 3 Trials of War Criminals Before the Nuremberg
Military Tribunals: “The Justice Case” 975 (1951). I cannot
agree that Bahlul is entitled to domestic constitutional
protections—to which he would not be entitled under
international law—simply because his war crimes trial was
held at an American naval base located in Cuba.

    Accordingly, were it not for the Government’s
concession that the Ex Post Facto Clause protects Bahlul, I
would reach the issue and conclude that it does not.1




    1
       Responding briefly to Judge Kavanaugh’s concurrence, and
with respect, I believe he is a solo source of confusion. He persists
in reading the majority opinion to resuscitate Hamdan II. Cf.
Kavanaugh Op. 1. He is wrong. I leave it to the careful reader to
discern, not surprisingly, that the majority expressly overrules
Hamdan II’s statutory holding. See Majority Op. 15. Judge
Kavanaugh then pivots, calling the majority’s decision to
“ ‘overrule[]’ ” Hamdan II’s “statement” “a meaningless exercise.”
Kavanaugh Op. 27. Despite his best efforts at revisionism, the fact
of the matter is that Hamdan II was wrongly decided and today the
majority so holds.
     ROGERS, Circuit Judge, concurring in the judgment in part
and dissenting. Ali Hamza Ahmad Suliman al Bahlul, a self-
avowed member of al Qaeda who has been held in the Naval
Base at Guantanamo Bay, Cuba since 2002, was convicted and
sentenced to life imprisonment by a military commission for
three offenses under the Military Commissions Act of 2006.
The question before the en banc court is whether these charges
support the jurisdiction of the military commission. See Order,
Apr. 23, 2013. Because Bahlul’s conduct occurred prior to the
enactment of the 2006 Act, and the military commission lacked
jurisdiction to try these non-law-of-war offenses, Bahlul’s
convictions must be vacated. The court is vacating Bahlul’s
convictions for material support and solicitation. For the
following reasons, I would also vacate Bahlul’s conviction for
inchoate conspiracy.

                                I.

     In Hamdan v. Rumsfeld, 548 U.S. 557, 590 (2006), the
Supreme Court observed that “[t]he military commission, a
tribunal neither mentioned in the Constitution nor created by
statute, was born of military necessity.” Historically, such
commissions have been used in three situations. Id. at 595
(plurality op.); id. at 683 (Thomas, J., dissenting). First, they
have substituted for civilian courts where martial law has been
declared. Second, they have tried civilians in occupied enemy
territory or territory regained from an enemy where civilian
government cannot function. Third, military commissions have
been convened to try “enemies who in their attempt to thwart or
impede our military effort have violated the law of war.” Ex
Parte Quirin, 317 U.S. 1, 28–29 (1942). This third type of
military commission is designed “to determine, typically on the
battlefield itself, whether the defendant has violated the law of
war.” Hamdan, 548 U.S. at 596–97 (plurality op.); cf. id. at 641
(Kennedy, J., concurring in part). Its jurisdiction is thus limited
                                 2

to “offenses cognizable during time of war.” Id. at 596
(plurality op.); see id. at 641 (Kennedy, J., concurring in part).

      “Trial by military commission raises separation-of-powers
concerns of the highest order.” Id. at 638 (Kennedy, J.,
concurring in part). “Every extension of military jurisdiction is
an encroachment on the jurisdiction of the civil courts, and,
more important, acts as a deprivation of the right to jury trial and
of other treasured constitutional protections.” Reid v. Covert,
354 U.S. 1, 21 (1957) (plurality op.); see id. at 41 (Frankfurter,
J., concurring in result); see also THE FEDERALIST NO. 47, at 324
(James Madison) (J. Cooke ed., 1961) (warning against the
“tyranny” created through the “accumulation of all powers
legislative, executive and judiciary in the same hands”). A
statute conferring judicial power outside the Article III courts
“may no more lawfully chip away at the authority of the Judicial
Branch than it may eliminate it entirely. ‘Slight encroachments
create new boundaries from which legions of power can seek
new territory to capture.’” Stern v. Marshall, 131 S. Ct. 2594,
2620 (2011) (quoting Reid, 354 U.S. at 39 (plurality op.)). Even
when confronted with the exigencies of war, “[the Court] cannot
compromise the integrity of the system of separated powers and
the role of the Judiciary in that system.” Id.

     The question presented by Bahlul’s appeal is the effect of
the 2006 Act on these settled principles. Given “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,” Quirin, 317 U.S. at 19, this court must assure itself that
the military commission had jurisdiction over the charged
offenses of which Bahlul was convicted. See Hamdan, 548 U.S.
at 611–12 (plurality op.); id. at 683 (Thomas, J., dissenting);
Application of Yamashita, 327 U.S. 1, 17–18 (1946); Quirin,
317 U.S. at 25; 10 U.S.C. § 950g(d). The court properly
considers a challenge to the jurisdiction of a military
                                 3

commission at any time it is raised. See R.M.C. 907(b)(1), THE
MANUAL FOR MILITARY COMMISSIONS, at II-87 (2007) (“A
charge or specification shall be dismissed at any stage of the
proceedings if: (A) The military commission lacks jurisdiction
to try the accused for the offense”); cf. FED. R. CIV. P. 12(h)(3)
(“If the court determines at any time that it lacks subject-matter
jurisdiction, the court must dismiss the action”); Arbaugh v.
Y&H Corp., 546 U.S. 500, 506 (2006) (“The objection that a
federal court lacks subject-matter jurisdiction, see FED. R. CIV.
P. 12(b)(1), may be raised by a party, or by a court on its own
initiative, at any stage in the litigation, even after trial and the
entry of judgment.”).

                                A.
     Congress enacted the Military Commissions Act of 2006,
Pub. L. No. 109-366, 120 Stat. 2600, to authorize the
establishment of law-of-war military commissions and to
establish procedures governing their use. The 2006 Act
specifies the “[c]rimes triable by military commissions,” 10
U.S.C. § 950v, including offenses such as attacking civilians, id.
§ 950v(b)(2), taking hostages, id. § 950v(b)(7), and torture, id.
§ 950(b)(11). Congress included an unequivocal statement of
the purpose and effect of its enactment:

         (a) PURPOSE. — The provisions of this subchapter
         codify offenses that have traditionally been triable by
         military commissions. This chapter does not establish
         new crimes that did not exist before its enactment, but
         rather codifies those crimes for trial by military
         commission.

         (b) EFFECT. — Because the provisions of this
         subchapter (including provisions that incorporate
         definitions in other provisions of law) are declarative
         of existing law, they do not preclude trial for crimes
                                4

         that occurred before the date of the enactment of this
         chapter.

Id. § 950p (emphases added). The court must “presume that
[the] legislature says in a statute what it means and means in a
statute what it says there.” Conn. Nat’l Bank v. Germain, 503
U.S. 249, 253–54 (1992). The words used by Congress are to be
understood in their ordinary, normal meaning, absent a contrary
indication. See Freeman v. Quicken Loans, Inc., 132 S. Ct.
2034, 2042 (2012).

     The reference in Congress’s plain and unequivocal
statement of purpose to “offenses that have traditionally been
triable by military commissions,” 10 U.S.C. § 950p(a) (emphasis
added), clearly indicates its intent to confine military
commissions to their traditional role and jurisdiction, not to
overturn settled principles. “Traditionally” is the adverbial form
of the word “traditional,” which means “long-established” or
“habitually done, used, or found.” THE NEW OXFORD
AMERICAN DICTIONARY 1785 (2d ed. 2005). A “tradition[]” is
readily identified and found in established practices; it is not
based on a “few scattered . . . anomalies.” NLRB v. Noel
Canning, No. 12-1281, slip op. at 21 (U.S. June 26, 2014). To
quote Henry James: “[I]t takes an endless amount of history to
make even a little tradition.” THE AMERICAN SCENE 164 (1907).
Thus sang Tevye in “Fiddler on the Roof” of “Tradition” that
has lasted for generations. Jerry Bock & Sheldon Harnick,
Prologue – Tradition, on FIDDLER ON THE ROOF (RCA Victor
1964).

     Congress’s unusual “effect” statement, that the 2006 Act’s
provisions are “declarative of existing law,” 10 U.S.C.
§ 950p(b), amplifies its instruction in the statement of purpose
to look to offenses traditionally triable by military commissions.
Here, Congress expresses sensitivity to the implicit
                                5

constitutional concerns arising from authorizing military
commissions to try persons for conduct predating the 2006 Act.
Its statement that the 2006 Act permits retroactive application
only for offenses previously triable by military commission
accords with the established “presumption against statutory
retroactivity,” and is the very antithesis of a contrary
“unambiguous directive” or “express command” requiring
retroactivity. Landgraf v. USI Film Products, 511 U.S. 244,
263, 270, 280 (1994); see also Calder v. Bull, 3 Dall. 386, 390
(1798) (opinion of Chase, J.); Martin v. Hadix, 527 U.S. 343,
354 (1999); Lindh v. Murphy, 521 U.S. 320, 325 (1997). This
presumption is “deeply rooted in our jurisprudence, and
embodies a legal doctrine centuries older than our Republic.”
Landgraf, 511 U.S. at 265.

     Ambiguity, if any, would arise, therefore, only in
identifying the offenses that “have traditionally been triable by
military commissions,” 10 U.S.C. § 950p(a), and the Supreme
Court has provided clear guidance on the resolution of this
question. Congress’s statement that the offenses it has listed are
“declarative of existing law,” id. § 950p(b), is a legal conclusion
that is subject to a judicial declaration of what the law is. See
Marbury v. Madison, 5 U.S. 137, 177 (1803); see also Noel
Canning, No. 12-1281, slip op. at 7. “[A] mistaken opinion of
the legislature concerning the law[] does not make law.”
Postmaster-General v. Early, 25 U.S. 136, 148 (1827); see also
United States v. Stafoff, 260 U.S. 477, 480 (1923) (Holmes, J).
Determining what offenses were “traditionally” tried by military
commissions according to “existing law” at the time of the
conduct underlying Bahlul’s convictions carries out Congress’s
expressly stated purpose, and is not an attempt to rewrite the
2006 Act’s listing of offenses because Congress was mistaken,
see Op. at 25.

    At the time of Bahlul’s charged conduct, the relevant statute
                                6

was Article 21 of the Uniform Code of Military Justice, 10
U.S.C. § 821 (2000). See Hamdan, 548 U.S. at 592–93; see also
Yamashita, 327 U.S. at 7; Quirin, 317 U.S. at 28. It confers
jurisdiction on military commissions over “offenders or offenses
that by statute or by the law of war may be tried by military
commissions.” 10 U.S.C. § 821 (2000). The only offenses then
listed by statute were spying and aiding the enemy, 10 U.S.C.
§§ 904, 906 (2000). Because Bahlul was not charged with either
of these offenses, the military commission trying him had
jurisdiction only over violations triable by military commission
under “the law of war.” See Hamdan, 548 U.S. at 613;
Yamashita, 327 U.S. at 17; Quirin, 317 U.S. at 29.

     For more than seventy years, the Supreme Court has
interpreted the “law of war” to mean the international law of
war. In Quirin, examining the predecessor statute to 10 U.S.C.
§ 821 — Article 15 of the Articles of War, which similarly
referenced “offenders or offenses that by statute or by the law of
war may be triable by such military commissions” — the Court
stated that in Article 15 Congress had “sanction[ed], within
constitutional limitations, the jurisdiction of military
commissions to try persons and offenses which, according to the
rules and precepts of the law of nations, and more particularly
the law of war, are cognizable by such tribunals.” 317 U.S. at
27–28 (emphasis added).            The Court reaffirmed its
understanding that the law of war is a “branch of international
law,” id. at 29, four years later in Yamashita. Discussing the
jurisdiction of the military commission, the Court looked to the
violations of the law of war “recognized in international law”
and consulted the Hague Conventions and the Geneva
Conventions. Yamashita, 327 U.S. at 14–16. “[W]hen a new
legal regime develops out of an identifiable predecessor, it is
reasonable to look to the precursor in fathoming the new law.”
Johnson v. United States, 529 U.S. 694, 710 (2000); see also
Hamilton v. Rathbone, 175 U.S. 414, 421 (1899). More
                                 7

recently, in addressing Section 821 in Hamdan, the Court
adhered to Quirin and Yamashita by looking to the body of
international law governing armed conflict. See Hamdan, 548
U.S. at 602–03 (plurality op.); id. at 641 (Kennedy, J.,
concurring in part); see also Memorandum from the Office of
Legal Counsel to the Attorney General 28, 30 (July 16, 2010),
printed in New York Times v. United States, No. 13-422-cv, slip
op. app. A (2d Cir. June 23, 2014) (describing the law of war as
international law).

                                 B.
     To demonstrate that the offenses of which Bahlul was
convicted are violations of the international law of war and
within the jurisdiction of his military commission, Supreme
Court precedent indicates that the “Government must 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.” Hamdan, 548 U.S. at 603
(plurality op.). For instance, in Quirin, the Court concluded that
a military commission had jurisdiction to try “unlawful
combatants” who surreptitiously entered the United States,
discarding their uniforms on arrival, for the purpose of
committing hostile acts involving destruction of life or property.
317 U.S. at 35–36. This charge, the Court explained, “has been
so recognized in practice both here and abroad, and has so
generally been accepted as valid by authorities on international
law that we think it must be regarded as a rule or principle of the
law of war.” Id. Similarly, in Yamashita, the Supreme Court
held that a military commission had jurisdiction to try an
invading Commanding General of the Imperial Japanese Army
for breach of his duty to control the members of his command,
by permitting them to commit atrocities against civilian
populations and prisoners of war, because the charge “plainly”
alleged a violation of the law of war, the purpose of which is “to
protect civilian populations and prisoners of war from brutality.”
                                8

327 U.S. at 13–18.

     The government has repeatedly conceded that the three
offenses of which Bahlul was convicted are not, and were not at
the time of Bahlul’s conduct, law-of-war offenses under
international law. See Resp’t’s Br. 34 (regarding conspiracy
only); Resp’t’s Pet. for Reh’g En Banc 1–2 (“the charges are not
sustainable under Hamdan II because they have not attained
recognition at this time as offenses under customary international
law”); Resp’t’s pre-Hamdan II Panel Br. 57 (“the offenses of
conspiracy, solicitation, and providing material support to
terrorism have not attained international recognition at this time
as offenses under customary international law”); Oral Argument
Tr. 15 (Sept. 30, 2013) (“we have conceded that [all three
offenses] are not violations of the international law of war”).
This should end the matter given Congress’s stated purpose and
effect in the 2006 Act, 10 U.S.C. § 950p. Instead, departing
from the instruction of more than half a century of Supreme
Court precedent, the government contends that the en banc court
can affirm Bahlul’s convictions on the basis of a U.S. common
(or U.S. domestic) law of war. Because the court is vacating
Bahlul’s convictions for material support for terrorism and
solicitation but not for inchoate conspiracy, see Op. at 3, I need
address only Bahlul’s jurisdictional challenges to his conviction
for inchoate conspiracy. It bears noting, however, that the
court’s analysis of the infirmities of the government’s U.S.
common law theory, based on Civil War military commissions
and field orders, in vacating two of Bahlul’s convictions applies
no less to his conviction for inchoate conspiracy. See Op. at 46,
49, 52.

    1. The trial record of the law-of-war military commission
makes clear Bahlul was charged and convicted of inchoate
conspiracy; his stand-alone conspiracy conviction did not depend
upon proof of the completion of any object offense (such as
                                9

murder) or proof that the overt acts in furtherance of the
conspiratorial agreement of which he was convicted (such as
preparing a propaganda video) were law-of-war offenses.

     First, the government elected not to charge Bahlul under the
Pinkerton doctrine under which he could have been found
vicariously liable for reasonably foreseeable substantive crimes
committed by his co-conspirators in furtherance of the
conspiracy. See Resp’t’s Br. 47; Pinkerton v. United States, 328
U.S. 640 (1946). The government also did not pursue the theory
that Bahlul had joined a joint criminal enterprise. At the
beginning of Bahlul’s trial, the prosecutor moved to strike the
charge that Bahlul had “join[ed] al Qaeda, an enterprise of
persons who share the common criminal purpose that involved,
at least in part, the commission or intended commission of one
or more substantive offenses triable by military commission.”
Trial Tr. 110.

     Second, the trial evidence allowed for conviction of no more
than inchoate conspiracy. The government’s evidence consisted
of Bahlul’s agreement with Usama bin Laden and other members
of al Qaeda to commit law-of-war offenses and his commission
of non-law-of-war, non-criminal overt acts in furtherance of the
agreement. (The government’s focus at trial was on Bahlul’s
role as an al Qaeda propagandist, in particular, his preparation of
a recruitment video entitled “The Destruction of the American
Destroyer U.S.S. Cole.”) None of the overt acts committed in
furtherance of the charged conspiracy — including traveling to
Afghanistan with the intent to join al Qaeda, undergoing
military-type training at a training camp sponsored by al Qaeda,
pledging fealty (or “bayat”) to Usama bin Laden, or transcribing
the martyr wills of two of the September 11th hijackers — is a
law-of-war offense. Even assuming being armed would have
sufficed, the military commission found Bahlul not guilty of the
overt act that he had “armed himself with an explosive belt, rifle,
                               10

and grenades to protect and prevent the capture of Usama bin
Laden.”

     Third, the presiding military judge instructed the members
of the military commission that to find Bahlul guilty of
conspiracy, they must find beyond a reasonable doubt that he
knowingly entered into an agreement to commit one or more
substantive offenses triable by military commission and that he
knowingly committed at least one overt act in furtherance of that
agreement. Trial Tr. 845–46. The judge further instructed that
proof the object of the conspiratorial agreement, the substantive
law-of-war offense, “actually occurred is not required” and
“[t]he overt act required for this offense does not have to be a
criminal act.” Id. at 848–49. The presiding judge also confirmed
that Bahlul was not being tried on the basis of a joint criminal
enterprise; when he discovered that his written instructions
included the word “enterprise,” the judge instructed the military
commission members to strike the words “or enterprise,”
explaining “that’s not before you,” id. at 881.

     2. The international law of war does not recognize inchoate
conspiracy as a law-of-war offense. Although there are two
exceptions — conspiracy to commit genocide and conspiracy to
wage aggressive war (also known as the commission of crimes
against peace), see Hamdan, 548 U.S. at 610 (plurality op.); 22
TRIAL OF THE MAJOR WAR CRIMINALS BEFORE THE
INTERNATIONAL MILITARY TRIBUNAL: NUREMBERG, 14
NOVEMBER 1945 – 1 OCTOBER 1946, at 469 (1948) (“TRIAL OF
MAJOR WAR CRIMINALS AT NUREMBERG”); Antonio Cassese,
International Criminal Law 191 (2003); see also Br. of Amici
Curiae Int’l Law Scholars 12–14 — the government does not
argue that either applies to Bahlul.

     Treaty law and international courts and tribunals have
refused to recognize inchoate conspiracy as a war crime because
                               11

of its potential for conflict with the international law-of-war
principle “that criminal guilt is personal, and that mass
punishments should be avoided.” TRIAL OF MAJOR WAR
CRIMINALS AT NUREMBERG at 500. Morever, the Anglo-
American concept of conspiracy is not known to some European
legal systems. See Telford Taylor, THE ANATOMY OF THE
NUREMBERG TRIALS: A PERSONAL MEMOIR 36 (1992)
(“Taylor”). Neither the Hague Conventions nor the Geneva
Conventions, which are the “major treaties on the law of war,”
includes inchoate conspiracy as an international law-of-war
offense. Hamdan, 548 U.S. at 603–04 (plurality op.); see
Convention with Respect to the Laws and Customs of War on
Land, July 29, 1899, 32 Stat. 1803, 1 Bevans 247; Convention
Respecting the Laws and Customs of War on Land, Oct. 18,
1907, 36 Stat. 2277, 1 Bevans 631; Geneva Convention for the
Amelioration of the Condition of the Wounded and Sick in
Armed Forces in the Field, Aug. 12, 1949, 6 U.S.T. 3114, 75
U.N.T.S. 31; Geneva Convention for the Amelioration of the
Condition of Wounded, Sick and Shipwrecked Members of
Armed Forces at Sea, Aug. 12, 1949, 6 U.S.T. 3217, 75 U.N.T.S.
85; Geneva Convention Relative to the Treatment of Prisoners of
War, Aug. 12, 1949, 6 U.S.T. 3316, 75 U.N.T.S. 135; Geneva
Convention Relative to the Protection of Civilian Persons in
Time of War, Aug. 12, 1949, 6 U.S.T. 3516, 75 U.N.T.S. 287;
Protocol Additional to the Geneva Conventions of 12 August
1949, and Relating to the Protection of Victims of International
Armed Conflicts, June 8, 1977, 1125 U.N.T.S. 3; Protocol
Additional to the Geneva Conventions of 12 August 1949, and
Relating to the Protection of Victims of Non-International
Armed Conflicts, June 8, 1977, 1125 U.N.T.S. 609.

     The International Military Tribunal convened at Nuremberg
“pointedly refused to recognize as a violation of the law of war
conspiracy to commit war crimes,” Hamdan, 548 U.S. at 610
(plurality op.), concluding that its charter “does not define as a
                                12

separate crime any conspiracy except the one to commit acts of
aggressive war.” TRIAL OF MAJOR WAR CRIMINALS AT
NUREMBERG at 469; see also Charter of the International
Military Tribunal, in Agreement for the Prosecution and
Punishment of the Major War Criminals of the European Axis,
Aug. 8, 1945, 59 Stat. 1544, 82 U.N.T.S. 280; Taylor at 550–53.
The Charter addressed the personal responsibility of the major
war criminals of the European Axis. See Charter arts. 1, 6–8.
The Tribunal was concerned that “overbroad application of the
conspiracy principle may drag innocent people into the
prosecution’s net.” Taylor at 553. The United States Military
Tribunals convened to try additional defendants also concluded
that they “ha[d] no jurisdiction to try any defendant upon a
charge of conspiracy considered as a separate substantive
offense.” 15 UNITED NATIONS WAR CRIMES COMMISSION, LAW
REPORTS OF TRIALS OF WAR CRIMINALS 90 (1949) (“LAW
REPORTS OF TRIALS OF WAR CRIMINALS”). In addition, the
Charter of the International Military Tribunal for the Far East did
not confer jurisdiction over inchoate conspiracies to commit war
crimes or crimes against humanity, only conspiracy to commit
crimes against peace. See Charter of the International Military
Tribunal for the Far East art. 5, Jan. 19, 1946, T.I.A.S. No. 1589,
4 Bevans 20.

     Modern statutes defining international law-of-war offenses
do not refer to conspiracy to commit such offenses (other than
genocide). See Rome Statute of the International Criminal
Court, July 17, 1998, 2187 U.N.T.S. 90; Statute of the
International Tribunal for the Former Yugoslavia, adopted by
S.C. Res. 827, U.N. Doc. S/RES/827 (1993), reprinted in 32
I.L.M. 1159, 1192; Statute of the International Tribunal for
Rwanda, adopted by S.C. Res. 955, U.N. Doc. S/RES/955
(1994), reprinted in 33 I.L.M. 1598, 1602; Statute of the Special
Court for Sierra Leone, Jan. 16, 2002, 2178 U.N.T.S. 138.
Additionally, international tribunals recognizing “joint criminal
                                13

enterprise” as a theory of liability for completed law-of-war
offenses have rejected a separate inchoate offense based on
“mere membership” or “conspiring to commit crimes,” and
instead recognize liability only for “participation in the
commission of the crime.” Prosecutor v. Milutinovic, Case No.
IT-99-37-AR72, Decision on Dragoljub Ojdanic’s Motion
Challenging Jurisdiction – Joint Criminal Enterprise, ¶ 26 (Int’l
Crim. Trib. for the Former Yugoslavia, Appeals Chamber, May
21, 2003); Rwamakuba v. Prosecutor, Case No. ICTR-98-44-
AR72.4, Decision on Interlocutory Appeal Regarding
Application of Joint Criminal Enterprise to the Crime of
Genocide, ¶ 30 (Oct. 22, 2004); see also Br. of Amici Curiae
Int’l Law Scholars 8–10.

     3. Given this historical background, the government has a
heavy burden to show that Congress’s purpose in enacting the
2006 Act extended to inchoate conspiracy as an “offense[] that
ha[s] traditionally been triable by military commissions,” 10
U.S.C. § 950p(a). The government begins by suggesting that “a
systemized body of international law establishing individual
criminal responsibility for specific acts during warfare”
commenced with the Hague Conventions of 1899 and 1907 and
“is a relatively modern innovation.” Resp’t’s Br. 28 (citing
Timothy L.H. McCormack, From Sun Tzu to the Sixth
Committee: The Evolution of an International Criminal Law
Regime, in THE LAW OF WAR CRIMES: NATIONAL AND
INTERNATIONAL APPROACHES 31, 43 (Timothy L.H. McCormack
& Gerry J. Simpson eds., 1997)). It continues by citing Colonel
William Winthrop, referred to by the Supreme Court as the
“Blackstone of Military Law,” Hamdan, 548 U.S. at 597
(plurality op.) (quoting Reid, 354 U.S. at 19 n.38 (plurality op.)),
for the proposition that prior to the adoption of these and later
treaties, the “offenses in violation of the laws and usages of war
[consisted of] those principally, in the experience of our wars,
made the subject of charges and trial.” Resp’t’s Br. 29 (quoting
                               14

William Winthrop, MILITARY LAW AND PRECEDENTS 839 (1920)
(“Winthrop PRECEDENTS”)). It also points to the reference in
Hamdan to “the American common law of war,” 548 U.S. at
613. Resp’t’s Br. 32. Neither Winthrop nor Hamdan advance
the government’s case for sustaining Bahlul’s conspiracy
conviction.

     First, in discussing the Civil War military commissions
relied upon by the government, Winthrop “excludes conspiracy
of any kind from his own list of offenses against the law of war.”
Hamdan, 548 U.S. at 608 (plurality op.) (citing Winthrop
PRECEDENTS at 839–40). Instead, Winthrop classifies the
relevant Civil War conspiracy cases either as “[c]rimes and
statutory offenses cognizable by State or U.S. courts, and which
would properly be tried by such courts if open and acting,” or as
a “combin[ation]” of such civilian crimes and “violations of the
laws and usages of war cognizable by military tribunals.”
Winthrop PRECEDENTS at 839 & n.5. Winthrop rejected the idea
that inchoate conspiracy could be triable by law-of-war military
commission, emphasizing that “the jurisdiction of the military
commission should be restricted to cases of offence consisting in
overt acts, i.e. in unlawful commissions or actual attempts to
commit, and not in intentions merely.” Id. at 841. In other
words, “‘overt acts’ constituting war crimes are the only proper
subject at least of those military tribunals not convened to stand
in for local courts,” Hamdan, 548 U.S. at 608 (plurality op.)
(citing Winthrop PRECEDENTS at 841 & nn.22, 23). The cases
cited by the government reveal that this is the manner in which
the Civil War military commissions proceeded. See infra pt.
I.C.1.

     Second, the Supreme Court’s reference to “the American
common law of war” in Hamdan, 548 U.S. at 613, is to U.S.
military commission tradition and practice as an additional
constraint on, not an alternative basis for, military commission
                                15

jurisdiction under Section 821. The Court stated that the
Uniform Code of Military Justice, which includes Section 821,
“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 [Uniform Code of Military Justice] itself,
insofar as applicable, and with the ‘rules and precepts of the law
of nations.’” Id. (quoting Quirin, 317 U.S. at 28). To come
within the “law of war” under Section 821, an offense must
constitute both a violation of the international law of war and a
violation of the law of war as traditionally recognized in U.S.
military commissions. This is necessary because, as the Court
explained in Quirin, there may be

         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 constitutionally triable only by a jury.

317 U.S. at 29. Consequently, in Quirin, Yamashita, and
Hamdan the Supreme Court sought to establish that the relevant
offense was a violation of the law of war under international law
and was recognized in U.S. military commissions. See Quirin,
317 U.S. at 35; Yamashita, 327 U.S. at 15–16; Hamdan, 548 U.S.
at 603 (plurality op.). Under these precedents, the practice of
U.S. domestic military commissions is irrelevant as long as
inchoate conspiracy is not an international law-of-war offense,
and the government conceded that it is not. Of course, to the
extent the government relies on the Military Commissions Act
of 2009, which refers to offenses that have “traditionally been
triable under the law of war or otherwise triable by military
commission” to support its argument that the statute embraces “a
class of offenses — lawfully triable in U.S. military commission
practice — that is broader than the group of offenses that are
                               16

currently prohibited by the international law of war,” Resp’t’s
Br. 28 (quoting 10 U.S.C. § 950p(d) (2009) (emphasis added)),
this cannot advance its position since Bahlul was tried under the
2006 Act.

     The legislative history of the 2006 Act also does not
advance the government’s position. The Report of the House
Armed Services Committee on H.R. 6054 states “[f]or the
reasons stated in Justice Thomas’s opinion [in Hamdan], the
Committee views conspiracy [to commit a war crime] as a
separate offense punishable by military commissions.” H.R.
REP. NO. 109-664, pt. 1, at 25 (2006). But Justice Thomas
expressly acknowledged that “conspiracy” was understood as a
law-of-war offense only when it went “beyond ‘intentions
merely,’” and involved “unlawful” overt acts, 548 U.S. at 703
(Thomas, J., dissenting). There was no occasion in Hamdan for
Justice Thomas to address the validity of a conspiracy charge
where, as in Bahlul’s case, “the overt act required . . . does not
have to be a criminal act,” Trial Tr. 849; Justice Thomas
observed that Hamdan was “charged with the overt acts of
providing protection, transportation, weapons, and other services
to the enemy, acts which in and of themselves are violations of
the laws of war,” 548 U.S. at 704 (citation omitted).

                               C.
     Even assuming, contrary to Supreme Court precedent, that
a U.S. common law of war tradition could serve as an
independent basis for sustaining convictions by law-of-war
military commissions for offenses that are not recognized under
the international law of war or by then-existing statute, the
government fails to establish a domestic tradition to sustain
Bahlul’s inchoate conspiracy conviction. It not only fails to
point to evidence comparable to the abundance of evidence “both
here and abroad” relied upon by the Supreme Court in Quirin,
317 U.S. at 31–35 & nn.10, 12, the government has not identified
                               17

a single case where military commission jurisdiction has been
sustained on the basis of a charge of inchoate conspiracy, much
less a charge of conspiracy with instructions defining the limits
of the government’s burden of proof that are comparable to those
in Bahlul’s case.

     1. The Civil War cases to which the government points are,
in fact, consistent with Winthrop’s position. Further, as the
Supreme Court cautioned, “[t]he Civil War precedents must . . .
be considered with caution” because military commissions
“operated as both martial law or military government tribunals
and law-of-war commissions” and thus “often charged hybrid
crimes mixing elements of crimes ordinarily triable in civilian
courts (like treason) and violations of the law of war.” Hamdan,
548 U.S. at 596 n.27, 609 n.37 (plurality op.); see also Winthrop
PRECEDENTS at 839 & n.5. For example, William Murphy, who
was tried by military commission in 1865, was charged with
“[c]onspiracy to burn and destroy steamboats and other property”
and also with “[v]iolati[ng] the laws and customs of war,” by in
fact burning and destroying a steamboat and by secretly crossing
enemy lines and attempting to destroy a second boat. G.C.M.O.
No. 107 (1866). These separate charges suggest that Murphy
was tried by a tribunal serving as both a martial law court and a
law-of-war military commission, and that the military
commission classified the conspiracy charge as a civil crime, not
as a “violation of the laws and customs of war.” Id. Only this
understanding is consistent with the fact that Murphy’s
conspiracy conviction was vacated because the civil courts were
open and therefore the military commission “had no jurisdiction
of his person or of his offence.” In re Murphy, 17 F. Cas. 1030,
1031, 1032 (1867). And because Murphy did in fact destroy a
steamboat during wartime, his case provides no support for the
government’s theory that a Civil War military tribunal had
jurisdiction over conspiracy absent proof, much less absent any
allegation, of a completed substantive law-of-war offense.
                                18

     Similarly, the case of Henry Wirz, also cited by the
government, does not provide evidence of a tradition on which
to base affirmance of Bahlul’s inchoate conspiracy conviction.
Confederate Army Captain Wirz was charged with conspiring to
injure the health and destroy the lives of soldiers in the military
service of the United States and “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.”
Hamdan, 548 U.S. at 609 (plurality op.) (citing H.R. Doc. No.
314, 55th Cong., 3d Sess., 785, 789–90 (1899)). Notably, as the
Hamdan plurality explained, the Judge Advocate General
determined that one of Wirz’s alleged co-conspirators, R.B.
Winder, should not be tried by military commission because
“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 such specific overt acts of violation
of the laws of war are as yet fixed upon [Winder].” Id. (quoting
H.R. Doc. No. 314, 55th Cong., 3d Sess., 783 (1899)) (emphasis
in original opinion). In other words, had Wirz not committed
overt acts that were violations of the law of war, he could not
have been tried by military commission for conspiracy.

     The 1865 trial of the Lincoln assassins, “even if properly
classified as a trial by law-of-war commission,” Hamdan, 548
U.S. at 604 n.35 (plurality op.), likewise does not support the
government’s theory of a U.S. common law-of-war tradition.
The defendants were charged with both “conspiring” to murder
President Lincoln and the completed offense of “maliciously,
unlawfully, and traitorously murdering the said Abraham
Lincoln,” G.C.M.O. No. 356 (1865); see Hamdan, 548 U.S. at
604 n.35 (plurality op.) (quoting H.R. Doc. 314, 55th Cong., 3d
Sess., 696 (1899)); see also THE TRIAL: THE ASSASSINATION OF
PRESIDENT LINCOLN AND THE TRIAL OF THE CONSPIRATORS
                                19

246–47 (Edward Steers, Jr. ed., 2003). Of utmost significance,
surely, the then-Attorney General, in defending the use of a
military tribunal, treated the charge as alleging the substantive,
completed “offence of having assassinated the President.” 11
Op. Atty. Gen. 297, 297 (1865). Furthermore, the district court,
in rejecting petitions for a writ of habeas corpus filed by three of
the assassins, described the charge of conviction as “a conspiracy
to commit the military crime [of the assassination of the
Commander in Chief] which one of their number did commit.”
Ex Parte Mudd, 17 F. Cas. 954 (S.D. Fla. 1868) (emphasis
added). Recall that in Bahlul’s case the prosecution dismissed
charges and theories of vicarious liability.

     In sum, the Civil War conspiracy cases, including the trial
of the Lincoln assassins, each, in fact, involved a completed law-
of-war offense, not an inchoate conspiracy. These cases are
consistent with Winthrop’s description of such conspiracies as
among the “[c]rimes and statutory offenses . . . which would
properly be tried by [State or U.S.] courts if open and acting,” or
alternatively, as hybrid crimes combining elements of crimes
ordinarily triable in civilian courts and law-of-war offenses.
Winthrop PRECEDENTS at 839 & n.5. They offer no reason to
depart from Winthrop’s contemporary rejection of inchoate
conspiracy as a law-of-war offense.

     2. The World War II cases cited by the government also do
not establish historical support for the jurisdiction of law-of-war
military commissions over inchoate conspiracy. Although the
Nazi saboteurs in Quirin were charged with conspiracy, the
Supreme Court affirmed their convictions based on the
independent charge that they had violated the law of war by
crossing behind enemy lines having removed their uniforms,
with the purpose of committing sabotage. See Quirin, 317 U.S.
at 48. “The offense was complete when with [hostile] purpose
they entered — or, having so entered, they remained upon — our
                               20

territory in time of war without uniform or other appropriate
means of identification.” Id. at 38. Like the case of the Lincoln
conspirators, Quirin involved a completed law-of-war offense,
not an inchoate conspiracy conviction like Bahlul’s. “If
anything, Quirin supports [the] argument that conspiracy is not
a violation of the law of war,” because “[t]he Court was careful
in its decision to identify an overt, ‘complete’ act” and “took
seriously the saboteurs’ argument that there can be no violation
of law of war — at least not one triable by military commission
— without the actual commission or attempt to commit a ‘hostile
and warlike act.’” Hamdan, 548 U.S. at 606–07 (plurality op.)
(quoting Quirin, 317 U.S. at 37–38). Brigadier General Mark
Martins, the Chief Prosecutor of Military Commissions in the
Department of Defense since June 2011, likewise characterized
Quirin as an authority “supporting [the] rationale” that
conspiracy may be tried under the law of war in conjunction with
a completed offense that appears on the charge sheet, but not as
an inchoate offense. Memorandum from Mark S. Martins, Chief
Prosecutor of Military Commissions, Dep’t of Defense, to the
Convening Authority 4 (Jan. 6, 2013).

     The government’s reliance on Colepaugh v. Looney, 235
F.2d 429 (10th Cir. 1956), is misplaced. The Tenth Circuit
followed Quirin in affirming the denial of a habeas petition filed
by another World War II saboteur. Colepaugh had been
convicted on three charges: (1) he “secretly passed through, in
civilian dress, contrary to the law of war, the military and naval
lines of the United States for the purpose of committing
espionage, sabotage and other hostile acts;” (2) he “appeared and
remained in civil dress, contrary to the law of war behind the
military lines of the United States for the purpose of committing
espionage, sabotage and other hostile acts;” and (3) “conspiracy
to commit the above substantive offenses.” Id. at 431. Like the
Supreme Court in Quirin, the Tenth Circuit looked to the “body
of international common law known as the law of war,” id. at
                                21

431–32, and concluded that Colepaugh was not entitled to relief
because he had committed the same substantive law-of-war
offense as the saboteurs in Quirin when he entered this country
and discarded his uniform for the purpose of committing hostile
acts involving the destruction of life or property, id. at 432
(quoting Quirin, 317 U.S. at 35). The court also followed the
Supreme Court in not confirming the validity of the separate
conspiracy charge. Consequently, this case, like Quirin,
provides no support for the government’s theory that Bahlul
could be tried by military commission for inchoate conspiracy
absent any charge that he committed a substantive law-of-war
offense.

    3. In sum, “[f]ar 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,” Hamdan, 548
U.S. at 611 (plurality op.) (citation omitted). As the plurality in
Hamdan explained:

         The crime of ‘conspiracy’ has rarely if ever been tried
         as such in this country by any law-of-war military
         commission not exercising some other form of
         jurisdiction, and does not appear in either the Geneva
         Conventions or the Hague Conventions — the major
         treaties on the law of war. Winthrop explains that
         under the common 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.

Id. at 603–04 (citing Winthrop PRECEDENTS at 841).
                                22

     Insofar as the government proposes, contrary to Supreme
Court precedent, a U.S. common law of war basis for sustaining
Bahlul’s conspiracy conviction, the government’s proposal is
also “unmoored from any enumerated power and has no rational
stopping place.” Pet’r’s Br. 32. Such a theory suggests that
modern military commissions could try defendants for any
offense that approximates a charge previously brought before
any type of military tribunal, including Civil War era military
commissions convened to try ordinary civilian crimes. See id.

     The government’s interpretation of Congress’s intent in
enacting the 2006 Act, additionally, leaves no room for
consideration of the reasons the international community has
rejected inchoate crimes as law-of-war offenses: for example,
their dragnet effect could sweep in and condemn as war
criminals the line soldier who merely pledged allegiance to the
enemy as well as the errant but innocent delivery boy or
shepherd who was on the wrong street at the wrong time. See
Taylor at 553; Br. of Amicus Curiae Int’l Law Scholars 7, 15–18.
The Supreme Court has long understood the role of military
commissions to arise from the military necessity in the midst of
war “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; Hamdan,
548 U.S. at 596 (plurality op.), not to try and convict (as distinct
from holding as prisoners of war) anyone who is a member of the
opposing forces. The law of war governing the use of military
commissions is a product of the costly lessons learned in the last
century from two World Wars, including the principle that, as a
matter of international law, law-of-war offenses are about
personal responsibility for war crimes, not collective guilt. See
TRIAL OF MAJOR WAR CRIMINALS AT NUREMBERG at 500. It
seems unlikely the Congress that enacted the 2006 Act intended
to cast aside such costly learning without expressly indicating
that it intended to do so; by using the phrase “offenses that have
                               23

traditionally been triable,” 10 U.S.C. § 950p(a) (emphasis
added), in stating its purpose, Congress signaled it was adhering
to the established understanding of the role of military
commissions, not breaking new ground.

     And, even assuming arguendo that practices of U.S. military
commissions could provide an independent basis upon which to
support the jurisdiction of a law-of-war commission to try an
offense not recognized in international law, nor codified in
statute at the time, the government’s failure to demonstrate that
such a “tradition[]” existed at the time of the charged conduct
requires vacatur of Bahlul’s inchoate conspiracy conviction.

      Were the implications for the separation of powers raised by
trial by military commission not “of the highest order,” Hamdan,
548 U.S. at 638 (Kennedy, J., concurring in part), the
government’s effort to establish its inchoate conspiracy theory on
the basis of so meager and deficient an historical showing that it
was among the “offenses that have traditionally been triable by
military commissions,” 10 U.S.C. 950p(a) (2006) (emphasis
added), might be less problematic. After all, the war on terror is
unlike recent wars waged among sovereign nations whose troops
wore identifiable uniforms, and two Presidents have employed
a modern “enemy combatant” military justice regime. See, e.g.,
Boumediene v. Bush, 553 U.S. 723, 733 (2008); Hamdan, 548
U.S. at 570 & n.1. But in codifying “offenses that have
traditionally been triable by military commissions” in the 2006
Act, Congress did not encourage or permit any blurring of the
jurisdictional lines between military commissions and Article III
courts. The Article III courts were open for prosecuting
September 11 perpetrators and other members of al Qaeda for
inchoate conspiracy or other federal crimes. Only years later did
Congress bar the President from using appropriated funds to
bring Guantanamo detainees into the United States for any
purpose. The President has opposed such restrictions on the
                               24

ground that they strip the Executive Branch of “the authority to
determine when and where to prosecute Guantanamo detainees,
based on the facts and circumstances of each case and our
national security interests” — when the Administration wishes
to employ federal prosecutions [in Article III courts] as “a
legitimate, effective, and powerful tool in our efforts to protect
the Nation.” See Statement by the President on H.R. 3304 (Dec.
26, 2013). So far, Congress has not been persuaded to remove
the restrictions. In the meantime, the court has a duty “in time
of war as well as in time of peace, to preserve unimpaired the
constitutional safeguards of civil liberty.” Quirin, 317 U.S. at
19. Hewing to the jurisdictional limits for law-of-war military
commissions, as Supreme Court precedent instructs, preserves
the separation of powers under which law-of-war military
commissions are confined to their historical role as necessities,
not conveniences, of war. Congress’s unequivocal statement of
its purpose and effect in section 950p of the 2006 Act is
consistent only with the understanding that it intended to
maintain the traditional jurisdictional lines.

                               II.

     There is still another reason why Bahlul’s conviction for
inchoate conspiracy (and the other two convictions) must be
reversed if the 2006 Act is applied retroactively. See Op. at 15.
Even assuming, contrary to its express statement of the intended
“effect” of the 2006 Act, 10 U.S.C. § 950p(b), that Congress
intended the 2006 Act to apply retroactively to create new
offenses triable by military commissions, Bahlul’s convictions
must be vacated under the Ex Post Facto Clause of the
Constitution. U.S. CONST. art. I, § 9, cl. 3.

                              A.
     Bahlul’s Ex Post Facto Clause challenge to his convictions
is properly reviewed de novo for any one of three reasons. In
                                25

applying a plain error standard of review, the majority imposes
a magic-words requirement nowhere to be found in the precedent
of the Supreme Court or in the Uniform Code of Military Justice
as interpreted by the Court of Appeals for the Armed Forces.
See, e.g., Olano v. United States, 507 U.S. 725 (1993).

     Bahlul unambiguously objected to his trial on the grounds
he was being charged with offenses that did not exist at the time
of his alleged conduct. Although he did not refer specifically to
the Ex Post Facto Clause, his pretrial colloquy with the presiding
military judge invoked its principles and alerted the military
commission to the substance of his objection, which is all that is
required to preserve an objection. See, e.g., United States v.
Breedlove, 204 F.3d 267, 270 (D.C. Cir. 2000). The Ex Post
Facto Clause is designed both “to assure that legislative Acts
give fair warning of their effect” and to “restrain[] arbitrary and
potentially vindictive legislation.” Weaver v. Graham, 450 U.S.
24, 28–29 (1981). Bahlul objected to the judge that after the
events of September 11, 2001, this country had “put on the side,
the meaningless American laws, the United Nations, . . . the
world codes, the international law and what branches out of it
and the international war laws and the Geneva Conventions and
the internal American law — military law, and the civil law —
American civil law” and instead had “legislated new laws and
this military commission.” Trial Tr. 23. Bahlul repeated that the
United States had “established a new law in the land, for me and
for any person that stands in front of you or before you in the war
in the entire world; but specifically, the Islamic world, and
specifically also, the Mujahideen Regime.” Id. at 24. He
accused the United States of “getting confused between laws and
going in an empty circle . . . [b]ecause today, you set a law that
would impact you tomorrow, and then you will change it, or
adjust it, or add to it.” Id. at 25.

    With these arguments, Bahlul expressly challenged the “new
                               26

laws and this military commission” that was to try him as
divorced from both international and American law principles
and as constructed after-the-fact for the purpose of trying
members of al Qaeda. Bahlul’s objections to “new laws” being
applied to him and to “chang[ing],” “adjust[ing],” and “add[ing]
to” existing laws are the considerations animating the ex post
facto prohibition. The presiding military judge understood
Bahlul’s arguments and his decision to “boycott” the military
commission proceedings to be a motion to dismiss for lack of
jurisdiction, because the law that created the proceedings was
unlawful or the charges did not state an offense. Id. at 98–99.

     Even if Bahlul had forfeited his ex post facto challenge, de
novo review of a forfeited issue is permitted where the lower
court has “nevertheless addressed the merits of the issue.”
Blackmon-Malloy v. Capitol Police Bd., 575 F.3d 699, 707 (D.C.
Cir. 2009) (citing United States v. Williams, 504 U.S. 36, 41
(1992)); see United States v. Hernandez-Rodriguez, 352 F.3d
1325, 1328 (10th Cir. 2003); cf. Milhouse v. Levi, 548 F.2d 357,
363 (D.C. Cir. 1976); United States v. Gorski, 47 M.J. 370, 375
(C.A.A.F. 1997). This principle applies in both criminal and
civil cases. See Williams, 504 U.S. at 41. The Court of Military
Commission Review considered Bahlul’s constitutional Ex Post
Facto Clause objection on the merits, 820 F. Supp. 2d 1141,
1218 (C.M.C.R. 2011), and this court may as a matter of
discretion consider Bahlul’s challenge under a de novo standard
of review. Given that Bahlul’s objections go to the fundamental
issue of the military commission’s jurisdiction, this court should
apply de novo review.

     Furthermore, under the Rules of Military Commissions,
Bahlul’s challenge to the military tribunal’s jurisdiction and the
charges against him cannot be waived or forfeited and is
reviewed de novo. Rule 905(e) provides, in relevant part, that
failure to raise defenses or objections or to make motions or
                                 27

requests “except lack of jurisdiction or failure of a charge to
allege an offense” at the appropriate time “shall constitute
waiver.” See THE MANUAL FOR MILITARY COMMISSIONS, at II-
83–84 (2007). The rule thus defines “waiver” to include
forfeiture. Similarly, Rule 907(b)(1), “Nonwaivable grounds,”
states that “[a] charge or specification shall be dismissed at any
stage of the proceedings if: (A) The military commission lacks
jurisdiction to try the accused for the offense; or (B) The
specification fails to state an offense.” Id. at II-87. As the
presiding military judge concluded, Bahlul’s retroactivity
objection is a claim that the charges against him fail to state an
offense. Cf. MOORE’S FEDERAL PRACTICE § 612.04 (Lexis 2014)
(“The defense of failure to charge an offense may be based on
. . . the unconstitutionality of the statute relied upon.”); see also
United States v. Haddock, 956 F.2d 1534, 1542 (10th Cir. 1992),
abrogated on other grounds by United States v. Wells, 519 U.S.
482 (1997); United States v. Gilbert, 813 F.2d 1523, 1528–29
(9th Cir. 1987); United States v. Seuss, 474 F.2d 385, 387 n.2
(1st Cir. 1973).

                                 B.
     The government concedes that the Ex Post Facto Clause
applies in military commission prosecutions under the 2006 Act
of detainees at Guantanamo Bay. See Resp’t’s Br. 64. This
conclusion follows from Boumediene, 553 U.S. at 766–71. Like
the Suspension Clause at issue there, the Ex Post Facto Clause
is “one of the few safeguards of liberty specified in a
Constitution that, at the outset, had no Bill of Rights,” id. at 739,
and serves both to protect individuals and to preserve the
Constitution’s separation-of-powers structure. See id. at 739–46;
Landgraf, 511 U.S. at 267–68; Weaver, 450 U.S. at 29 n.10.
“Because the Constitution’s separation-of-powers structure . . .
protects persons as well as citizens, foreign nationals who have
the privilege of litigating in our courts can seek to enforce
separation-of-powers principles.” Boumediene, 553 U.S. at 743.
                                28

The Court’s analysis of the extraterritorial reach of the
Suspension Clause applies to the Ex Post Facto Clause because
the detainees’ status and location at Guantanamo Bay are the
same, and the government has pointed to no distinguishing
“practical obstacles” to its application. See id. at 766. The 2006
Act, in providing that it “does not establish new crimes that did
not exist before its enactment,” 10 U.S.C. § 950p(a), fairly
demonstrates Congress’s implied recognition of the reach of the
fundamental protections embodied in the Ex Post Facto Clause.

      Ex post facto laws are “contrary to the great first principles
of the social compact,” Calder, 3 Dall. at 388 (opinion of Chase,
J.), and are “condemned by the universal sentence of civilized
man” as “oppressive, unjust, and tyrannical,” Ogden v. Saunders,
25 U.S. 213, 266 (1827). The Ex Post Facto Clause both
“ensures that individuals have ‘fair warning’ about the effect of
criminal statutes,” Landgraf, 511 U.S. at 267–68 (citation
omitted), and serves as a meaningful structural constraint
imposed by Article I that goes “to the very root of the power of
Congress to act all,” Downes v. Bidwell, 182 U.S. 244, 277
(1901) (opinion of Brown, J.); see also Weaver, 450 U.S. at
29–30. It “safeguards ‘a fundamental fairness interest . . . in
having the government abide by the rules of law it establishes to
govern the circumstances under which it can deprive a person of
his or her liberty or life.’” Peugh v. United States, 133 S. Ct.
2072, 2085 (2012) (quoting Carmell v. Texas, 529 U.S. 513, 533
(2000)). And it “upholds the separation of powers by confining
the legislature to penal decisions with prospective effect and the
judiciary and executive to applications of existing penal law.”
Weaver, 450 U.S. at 29 n.10.

     Tellingly, when ratified and now, the Ex Post Facto Clause
addresses the risk that, in response to political pressures, the
legislature “may be tempted to use retroactive legislation as a
means of retribution against unpopular groups or individuals.”
                              29

Landgraf, 511 U.S. at 266; see Weaver, 450 U.S. at 29. By
safeguarding the boundaries between the branches of
government, the Clause promises that accusations that this
country has, in Bahlul’s words, “put [our laws] on the side” and
“established a new law” for our enemies, Trial Tr. 23–24, will
lack merit. Yet in an odd turn of phase for addressing “one of
the most basic presumptions of our law,” Johnson, 529 U.S. at
701, the government urges that the Clause “should apply
flexibly” here “because of the common law nature of military
proceedings” and “because Bahlul’s conduct was criminal when
done,” albeit under statutes providing for prosecution in an
Article III court. Resp’t’s Br. 62–63, 67. The government’s
“flexible” approach to the Ex Post Facto Clause, relying on the
position that Bahlul’s conduct may have been proscribed by laws
other than those under which he was charged and convicted, “is
a standardless exercise in crime by analogy,” Pet’r’s Reply Br.
21, that the Supreme Court has condemned, see, e.g.,
Papachristou v. Jacksonville, 405 U.S. 156, 168–69 (1972), and
the law of war forbids, see, e.g., Rome Statute of the
International Criminal Court art. 22, July 17, 1998, 2187
U.N.T.S. 90; 6 LAW REPORTS OF TRIALS OF WAR CRIMINALS at
95 (practices such as “application of principles of law
condemned by the practice of civilised nations such as
punishment by analogy . . . are all properly classed as war
crimes”).

                               C.
     Article I military commissions are an extraordinary tool
designed to permit the military to infringe on the Article III
power of the judiciary only to accomplish specific and discrete
objectives. Through the use of military commissions, the
government can provide a substitute for civilian courts in
occupied territories and in places where martial law has been
declared. See Hamdan, 548 U.S. at 595–96 (plurality op.); see
id. at 683 (Thomas, J., dissenting). As relevant here, military
                               30

commissions may be convened as an “incident to the conduct of
war,” to prosecute law-of-war offenses. Quirin, 317 U.S. at
28–29; see Hamdan, 548 U.S. at 596–97 (plurality op.); 10
U.S.C. § 948b(a) (2006). The retroactive expansion of the
jurisdiction of Article I law-of-war military commissions to
include offenses that “have [not] traditionally been triable by
military commissions,” however, contravenes the structural
limitations embodied in the Ex Post Facto Clause.

     This appears to be a test case brought by the government to
establish the jurisdiction of law-of-war military commissions
over inchoate conspiracy where the government has evidence the
defendant entered into an agreement to engage in terrorist acts
against the United States, but no evidence the defendant
committed an overt act that was a law-of-war offense in
furtherance of the agreement. This approach may assist the
Executive Branch in surmounting obstacles to prosecutions in
Article III courts caused by Congress’s recent restrictions on the
use of appropriated funds to bring Guantanamo detainees into the
United States. See, e.g., Statement by the President on H.R.
3304 (Dec. 26, 2013). But it puts at risk the separation of powers
and the ex post facto principle by ignoring Congress’s plain
statement of purpose and effect in the 2006 Act, the
“traditional[]” jurisdiction of military commissions, and the
international community’s rejection of inchoate offenses as law-
of-war offenses.

     Accordingly, the inchoate conspiracy charge of which
Bahlul was convicted under the 2006 Act does not support the
jurisdiction of the military commission and this conviction must
be vacated as well as the two convictions vacated by the court.
All three convictions must be vacated as violations of the Ex
Post Facto Clause. It remains for the Administration to decide
whether to bring other charges against Bahlul before a military
commission or whether to charge him in an Article III court. To
                               31

the extent that Congress has created an obstacle to bringing
Bahlul to the United States, Congress can remove it. The
question whether Congress has impermissibly intruded upon the
President’s Article II powers is not before the court. In the
meantime, “[t]he laws and Constitution are designed to survive,
and remain in force, in extraordinary times. Liberty and security
can be reconciled; and in our system they are reconciled within
the framework of the law.” Boumediene, 553 U.S. at 798. I
concur in the judgment vacating Bahlul’s convictions for
material support and solicitation, and I respectfully dissent with
regard to affirmance of Bahlul’s conviction for inchoate
conspiracy.
     BROWN, Circuit Judge, concurring in the judgment in
part and dissenting in part: Over five years ago, Ali Hamza
Ahmad Suliman al Bahlul was convicted of conspiracy,
solicitation, and providing material support for terrorism.
Since that time, the government has been defending the
conviction, first before the Court of Military Commission
Review and now before this court. In this appeal, the
government seeks clarification of the prosecutorial tools it can
employ in the war on terror. While I concur in the court’s
judgment affirming Bahlul’s conspiracy conviction and
vacating the solicitation and material support convictions, I
cannot agree with the way the court reaches that result. By
reviewing Bahlul’s claims under a plain error standard, the
court minimizes the value its opinion might provide to the
government in future prosecutions. And by remanding
residual issues to a panel, the court delays resolution of
Bahlul’s case.

     I would definitively answer the important questions
raised by Bahlul’s appeal, reviewing his ex post facto
arguments under a de novo standard. I would also affirm
Congress’s power under the Define and Punish Clause to
make certain offenses, including conspiracy, triable by
military commission. This legal saga has endured long
enough, and we should take this opportunity to resolve
important legal questions that have arisen from the war on
terror.

                                I

     The opinion of the court provides insightful legal and
historical background and, in certain areas, well-reasoned
analysis. The separate opinions of Judges Henderson and
Kavanaugh afford additional insight. There is much in those
opinions with which I wholeheartedly agree. But although I
concur in the court’s judgment, I would reach its conclusion
through a slightly different path. In this section, I draw on the
                               2
compelling analysis of my colleagues to explain briefly how I
would dispose of Bahlul’s challenges. In the following
sections, which contain the analytical bulk of my concurrence,
I address three issues that I feel are not adequately covered by
the other opinions: the applicability of ex post facto
principles to Bahlul’s convictions, Bahlul’s challenge to
Congress’s power under the Define and Punish Clause, and
the court’s decision to remand remaining issues to a panel of
this court.

     I begin by noting the areas where I agree with my
colleagues. First, for the reasons expressed by Judge
Kavanaugh, I would review Bahlul’s Ex Post Facto Clause
and retroactivity arguments under a de novo standard. See
Opinion of Judge Kavanaugh (Kavanaugh Op.) 30–34; see
also Opinion of Judge Rogers Part II.A. Bahlul asked the
Military Judge presiding over his trial a “legal question” that,
although not a model of clarity, was sufficient to preserve
those arguments: “Does the law here start from before,
during, or after?” Supp. App. 37. Furthermore, Rules 905
and 907 of the Rules of Military Commissions make
jurisdictional challenges—including Bahlul’s—not subject to
forfeiture.

     Second, I agree with the court that the Military
Commissions Act (MCA) of 2006 unambiguously authorizes
retroactive prosecution for all the crimes enumerated in that
statute. See Op. Part III. Both the text of the Act—including
in particular 10 U.S.C. § 948d(a) (2006) (granting military
commissions           jurisdiction        over        offenses
“committed . . . before, on, or after September 11, 2001”)—
and the context of the judicial–legislative dialogue in which
the Act was passed require this conclusion.
                                3
     Third, like the court, I would accept, for the purposes of
this case only, the government’s concession that the Ex Post
Facto Clause provides its protection to aliens detained at
Guantanamo. See Op. 26–28. However, I doubt the
correctness of the government’s concession. If our review of
the question were de novo, I would, like Judge Henderson,
apply the longstanding precedents of the Supreme Court and
this court and conclude that the Ex Post Facto Clause does not
apply to Bahlul or other aliens at Guantanamo. See Opinion
of Judge Henderson.

     Fourth, I would reject Bahlul’s Ex Post Facto Clause
challenge as it concerns his conspiracy conviction. As Judge
Kavanaugh explains, prior to 2006, the “law of war”
provision of 10 U.S.C. § 821 (Article 21 of the Uniform Code
of Military Justice) preserved the jurisdiction of military
commissions to try offenses that (1) were codified in federal
statutes and explicitly made triable by military commission,
(2) were recognized by the international law of war, or (3)
were, according to domestic tradition and practice, triable by
military commission. See Kavanaugh Op. 7–11; cf. Op. 36–
40 (holding such a conclusion is not plainly erroneous).
Furthermore, as the Lincoln conspirators’ cases, Quirin,
Colepaugh, and the Korean War decisions demonstrate,
domestic practice traditionally treated conspiracy as an
offense triable by military commission. See Kavanaugh Op.
11–16; cf. Op. 40–44 (reaching similar conclusion under a
plain error standard). Because conspiracy was an offense
triable by military commission before the 2006 MCA,
Bahlul’s prosecution for that offense did not violate the Ex
Post Facto Clause. 1

1
  In upholding Bahlul’s conspiracy conviction, I would not rely on
18 U.S.C. § 2332(b). Indeed, by relying on Olano’s fourth prong,
the court practically concedes that the existence of the conspiracy
                                 4

    Fifth, I fully agree with the court’s discussion of material
support and solicitation and its conclusion that those offenses
were not historically triable by military commission. See Op.
Part IV.B–C. Thus, I join the court’s decision to vacate
Bahlul’s convictions for those offenses.

                                 II

     As noted above, if not for the government’s concession, I
would hold that, as an alien detained outside the sovereign
territory of the United States, Bahlul is not entitled to the
protections otherwise afforded by the Ex Post Facto Clause.
However, despite my doubts about the extraterritorial
applicability of the Clause, I do not doubt that its underlying
principles apply to detainees at Guantanamo. The legal
principle nullum crimen sine lege, found in the common law
and international law, constrains the power of the United
States to prosecute wherever it may do so. But, even if there
were not a long history of conspiracy charges being tried by
military commission, invocation of the ex post facto principle
alone could not help Bahlul or similarly situated detainees.
As the International Military Tribunal convened at

provision in Title 18 would not save Bahlul’s conviction if not for
the court’s application of a plain error standard. See Op. 32–35. I
am also reluctant to rely on that provision, however, because of the
significant procedural differences between criminal prosecutions in
Article III civilian courts and prosecutions before military
commissions. The parties have not fully briefed the issue, and I
would be reluctant without such briefing to hold that a law
retroactively transferring jurisdiction to try an offense from an
Article III court to a military commission does not violate the Ex
Post Facto Clause. Because the court utilizes a plain error standard,
the court also does not fully embrace this novel and potentially far-
reaching result.
                               5
Nuremberg in the aftermath of World War II thoughtfully
observed, “the maxim nullum crimen sine lege is not a
limitation of sovereignty, but is in general a principle of
justice.” Judgment of October 1, 1946, 1 INTERNATIONAL
MILITARY TRIBUNAL, TRIAL OF THE MAJOR WAR CRIMINALS
(IMT) 171, 219 (1947).

     During the proceedings of the International Military
Tribunal, the defendants, who were charged with conspiring
to wage aggressive war, complained that ex post facto
punishment was abhorrent to the law of all civilized nations
and that no sovereign power had made aggressive war a
crime, no statute defined aggressive war, no penalty had been
fixed for its commission, and no court had been created to try
and punish offenders at the time the acts were committed.
Nevertheless, the Tribunal recognized that its expression of
the international law was “itself a contribution to international
law” and, in setting up the Tribunal, several nations had done
together what any nation had a right to do singly. Id. at 218.
The Tribunal stated that “[t]o assert that it is unjust to punish
those who in defiance of treaties and assurances have attacked
neighboring states without warning is obviously untrue, for in
such circumstances the attacker must know that he is doing
wrong, and so far from it being unjust to punish him, it would
be unjust if his wrong were allowed to go unpunished.” Id. at
219.

    In the case of the terrorist attacks of September 11,
involving the murder of thousands of civilians, the attackers
knew the civilized world would condemn their actions.
Bahlul was fully aware of how the world would view his
complicity in a moral evil, and “so far from it being unjust to
punish him, it would be unjust if his wrong were allowed to
go unpunished.” See id.
                                6
                               III

    Bahlul argues Congress does not have the power under
the Define and Punish Clause to make triable by military
commission those offenses not proscribed by the international
law of war. The court remands this issue to the panel. But
the issue was fully briefed and argued before the en banc
court and, for the reasons explained below, see infra Part IV, I
think we should take the opportunity to resolve Bahlul’s
challenge now.

     Judge Kavanaugh would resolve this challenge by
holding that Congress’s authority to establish military
commissions derives not only from the Define and Punish
Clause, but from Congress’s war powers more generally,
including those originating in the Declare War and Necessary
and Proper Clauses of Article I, Section 8. See Kavanaugh
Op. Part II. Judge Kavanaugh notes that the war powers
clauses do not refer to international law and are not defined or
constrained by that law.          While I agree with Judge
Kavanaugh’s broad characterization of Congress’s war
powers, I find his resolution of Bahlul’s claim incomplete.
By looking to Congress’s authority under the war powers
clauses, Judge Kavanaugh leaves unresolved the argument
that Congress’s power under the Define and Punish Clause is
strictly constrained by international law. I would resolve
Bahlul’s challenge to Congress’s Define and Punish Clause
powers on Define and Punish Clause grounds alone, holding
that the Clause gives Congress far greater powers than Bahlul
acknowledges. 2

2
  Judge Kavanaugh’s reliance on the war powers clauses leaves
unresolved questions such as whether the government may try
before a military commission members of a terrorist organization
with which the United States is not engaged in active hostilities.
                               7

      Any discussion of the Define and Punish Clause must
take proper account of two separate but related points. First,
in drafting the Clause, the Framers were distinctly aware of
the undefined and adaptable nature of international law. They
also recognized the concomitant flexibility inherent in that
law. And they understood that the United States could, and
indeed should, make use of that flexibility to advance its own
national security interests. That is, the Framers intended the
United States—like other nations—to act in its own self-
interest, albeit within the flexible constraints of international
law.      Second, the Framers deliberately placed the
responsibility and prerogative to interpret and define
international law with Congress—a political branch—rather
than with the judiciary. This second point is related to the
first and to some extent demonstrates its truth: If the Framers
had intended the country to be strictly constrained by
narrowly-interpreted international law, it would have made
more sense to place the power to interpret that law with the
judiciary—the legal branch expert in such tasks. But, instead,
the Framers placed the power with Congress, intending that
Congress would interpret and define international law in a
more flexible way that serves the country’s self-interest, but
still remains compatible with international norms. The
Framers recognized the discretion that must necessarily be
exercised in defining international law, and entrusted that
discretion to Congress. The judiciary was given only very
limited power to review Congress’s choices in defining and
punishing violations of international law, and must exhibit
tremendous deference to the legislature’s choices in this area.

     With respect to the two principles described above,
Congress’s decision to make conspiracy an offense triable by
military commission provides an excellent example of the
                              8
flexibility inherent in international law and ably demonstrates
congressional prerogatives.

                              A

                              1

     The history behind the Define and Punish Clause
supports an expansive reading of Congress’s power under the
Clause. Both the drafters of the Constitution and their
eighteenth-century audience would have had more than a
passing familiarity with Blackstone and Locke—and, perhaps,
Vattel, Grotius, and other theorists—whose writings not only
suggest the law of nations was the special domain of the
executive and legislative branches, not the judiciary, but also
tend to emphasize the protean quality of international law.
See THE FEDERALIST NO. 42, at 260 (James Madison)
(Clinton Rossiter ed., 1961) (referring to the Define and
Punish Clause as one of the “class of powers, lodged in the
general government . . . which regulate the intercourse with
foreign nations”); BERNARD BAILYN, THE IDEOLOGICAL
ORIGINS OF THE AMERICAN REVOLUTION 27–31 (1967);
FORREST MCDONALD, NOVUS ORDO SECLORUM:                     THE
INTELLECTUAL ORIGINS OF THE CONSTITUTION 7, 60, 80
(1985).

     The Framers were committed to a national government
agile enough to avoid foreign entanglements and strong
enough to deter aggression. In part, it was the country’s
weakness in the face of decades of depredations by pirates in
the pay of the despots of the Barbary States that added
urgency to the constitutional convention. In 1785, when
emissaries Thomas Jefferson and John Adams sought a
diplomatic solution to America’s piracy problems, Abd al-
Rahman, the representative of Tripoli’s pasha, coolly
                               9
reiterated his nearly one-million-dollar ransom demand, and
replied to their peace overtures in terms that would be familiar
to contemporary Americans. He told the emissaries: “all
Nations who should not have acknowledged [the Muslims’]
authority were sinners, that it was [Islam’s] right and duty to
make war upon whoever they could find and to make Slaves
of all they could take as Prisoners, and that every Mussulman
who should be slain in battle was sure to go to Paradise.”
MICHAEL B. OREN, POWER, FAITH, AND FANTASY: AMERICA
IN THE MIDDLE EAST, 1776 TO THE PRESENT 26–27 (2007).
And the fledgling U.S. Republic continued to be victimized,
paying as much as a tenth of the national treasury to ransom
its citizens and its ships until well into the nineteenth century
when President Jefferson finally had a navy equal to the task
of freeing some shipping lanes. It is inconceivable that the
drafters, cognizant of this unhappy history and understandably
wary of the agendas and motives of European powers, would
have intended a reference to the law of nations to limit
America’s ability to defend its sovereignty and its citizens to
only such actions as some international consortium
sanctioned.       Cf. NOTES OF DEBATES IN THE FEDERAL
CONVENTION OF 1787, REPORTED BY JAMES MADISON 637,
(W. W. Norton & Co. 1987) (debate on the Define and Punish
Clause); THE FEDERALIST NOS. 16, 66, 68 (Alexander
Hamilton).

     More importantly, the Framers clearly understood that
parity among sovereign states is an aspect of power.
Customary international law is often just another name for
enlightened self-interest. The philosophical and cultural
environment in which the Constitution developed was
permeated by the premise of natural law at the core of the
Constitution. The drafters saw nothing odd in the idea that
nation-states could commit wrongs or that wronged states
could punish bad behavior, provided they were strong enough
                              10
to do so. America is not just the passive subject of the law of
nations; it is a participant of and contributor to it. No one
doubts the right of all nations “to resort to forcible means for
the purpose of repressing any one particular nation who
openly violates the laws of the society which Nature has
established between them, or who directly attacks the welfare
and safety of that society.” EMMERICH DE VATTEL, THE LAW
OF NATIONS, Preliminaries § 22, at 61 (photo. reprint 2005)
(1854). Punishment contemplated a spectrum of coercive
means up to and including war. Thus, Congress’s power to
punish offenses against the law of nations comprehended a
power to invoke a range of coercive means to preserve and
maintain the law of nations. These sentiments are also part of
the organic law of nations. See J. Andrew Kent, Congress’s
Under-Appreciated Power to Define and Punish Offenses
Against the Law of Nations, 85 TEX. L. REV. 843, 927 (2007)
(“The collective enforcement of the law of nations envisioned
by Vattel, Grotius, and others included the power to punish
through warfare pirates, terrorists, and other sub-state violent
groups.”); see also VATTEL, THE LAW OF NATIONS, supra, bk.
III § 34, at 407 (“[P]rofessed assassins and incendiaries are
guilty, not only towards the particular victims of their
nefarious deeds, but also towards the state, which therefore
proclaims them public enemies. All nations have a right to
join in a confederacy for the purpose of punishing and even
exterminating those savage nations.”).

     Moreover, the law of nations includes not only what is
mandated, such as compliance with self-executing treaty
obligations, but also what is permitted. See, e.g., HUGO
GROTIUS, THE LAW OF WAR AND PEACE, bk. 2, ch. 20, § 40,
226–27 (Walter J. Black 1949) (1625) (permitting nations to
wage war not only for wrongs committed against themselves,
but also for wrongs against nature). As one drafter explained:
“The law of nature, when applied to states or political
                               11
societies, receives a new name, that of the law of nations.”
JAMES WILSON, OF THE LAW OF NATIONS, in 1 THE WORKS OF
JAMES WILSON 148 (Robert Green McCloskey, ed., Harvard
Univ. Press 1967) (1804).

      Commentaries and treatises attempted to summarize how
natural rights applied to relations between nations. In fact, the
full title of Vattel’s work is The Law of Nations Or, Principles
of the Law of Nature, Applied to the Conduct and Affairs of
Nations and Sovereigns. Thus, such treatises acknowledged
the undisputed right of each nation to preserve its national
existence, to punish the violation of its laws, and to defend its
polity and protect its property, and condemned unwarranted
violence, conquest, and lawlessness. Vattel distinguishes the
Positive law of nations (based on treaties, convention, and
custom) from the Natural or Necessary law of nations. “As to
the rights introduced by Treaties or by Custom, there is no
room to apprehend that any one will confound them with the
Natural law of nations.” VATTEL, THE LAW OF NATIONS,
supra, Preliminaries § 27, at 63. To the extent these laws
originated as precepts of reason derived from the law of
nature, it makes sense that the law can change in response to
the exigencies of new species of violence.

    The few early cases interpreting the Define and Punish
Clause acknowledged the flexibility inherent in international
norms and deference to the exclusive congressional
prerogatives the clause prescribes. In United States v. Smith,
18 U.S. (5 Wheat.) 153 (1820), Justice Story noted offenses
against the law of nations “cannot, with any accuracy, be said
to be completely ascertained and defined in any public code
recognised by the common consent of nations.” Id. at 159.
He acknowledged that Congress could provide its own
enumeration of offenses or leave the definition, “without
inconvenience to the law of nations.” Id. at 158.
                               12

     In United States v. Arjona, 120 U.S. 479, 487–88 (1887),
Chief Justice Waite held that Congress may punish an
individual who counterfeits another nation’s money because
the law of nations generally requires prevention of a wrong
within one nation’s dominion against a nation with whom it is
at peace.      Thus, Congress could define and punish
counterfeiting as a violation of the law of nations even though
counterfeiting was not a widely recognized offense like
piracy. And there are other early indications from the
Supreme Court that no mandate in the Constitution requires
Congress to follow strictly the law of nations. See, e.g., Ware
v. Hylton, 3 U.S. (3 Dall.) 199, 224 (1796) (Chase, J.)
(“Suppose a general right to confiscate British property, is
admitted to be in Congress, and Congress had confiscated all
British property within the United States, including private
debts: would it be permitted to contend in any court of the
United States, that Congress had no power to confiscate such
debts, by the modern law of nations? If the right is conceded
to be in Congress, it necessarily follows, that she is the judge
of the exercise of the right, as to the extent, mode, and
manner.”); id. at 266 (Iredell, J.) (noting “[t]he power . . . of
the Legislature of the Union [is limited] by the Constitution of
the Union” but acknowledging that when the legislature acts
within a discretion expressly confided by the Constitution its
enactments are “in all cases obligatory”).

     As Justice Story observed in Smith, the international
law’s resistance to facile formulas led the Framers to entrust
Congress with the “power to define” the laws of nations. 18
U.S. at 159. The range and fluidity of international law, the
distinctive needs of each nation-state, and dangers of faction
to a system that relies on myriad sources establishing a
consensus of nation-state opinion and practice increased the
                               13
necessity for carving out a zone of deference for Congress’s
authority.

     The Framers labored to separate law from politics
because they knew that without that boundary, everything
would be politics. They (wisely) perceived that law is
(mostly) clear and categorical while politics—statecraft,
diplomacy, warfare—is murky, a realm Justice Jackson
evocatively dubbed the “zone of twilight.” Youngstown Sheet
& Tube Co. v. Sawyer, 343 U.S. 579, 637 (1952) (Jackson, J.,
concurring). The structure of the Constitution echoes this
rhetorical divide. On the political side, the Define and Punish
Clause is included in Article I, Section 8, grouped with the
other enumerated war powers such as declaring war, raising
armies, maintaining a navy, and issuing letters of marque and
reprisal. On the legal side, the Ex Post Facto Clause in
Section 9 is part of a list of prohibitions limiting and defining
the power of the national government over sovereign states
and the polity newly subject to national power. The single
exception to this categorization may be the prohibition on
suspension of the Writ of Habeas Corpus, and that limitation
can be overridden when it threatens the defense powers
authorized by Section 8. Cf. Robert J. Pushaw, Jr., The
Inherent Powers of Federal Courts and the Structural
Constitution, 86 IOWA L. REV. 735, 744–47 (2001); Martin H.
Redish, Federal Common Law, Political Legitimacy, and the
Interpretive Process: An “Institutionalist” Perspective, 83
NW. U. L. REV. 761, 765 (1989).

     Thus, both the history and the placement of the clause
demonstrate the power to define and punish was intended to
give Congress flexibility in protecting national security, not to
constrain the country’s ability to act by reference to
international norms. They also suggest the power is a unique
                               14
legislative power separate from traditional federal court
jurisdiction.

                               2

    More modern authorities demonstrate that international
law has remained as flexible a concept today as it was in
1789. Like all common law, the law of war is part of an
evolving process. As the International Military Tribunal at
Nuremberg explained:

    [I]nternational law is not the product of an international
    legislature, and . . . international agreements . . . have to
    deal with general principles of law . . . . The law of war
    is to be found not only in treaties, but in the customs and
    practices of states which gradually obtained universal
    recognition, and from the general principles of justice
    applied by jurists and practised by military courts. This
    law is not static, but a continual adaptation follows the
    needs of a changing world.

1 IMT 221.

     The international law of war is an evolving effort to
protect civilians from the horrors of total war. Weaponry and
modes of warfare change; human nature does not. Customary
understandings about the international law of war are revised
to account for the impact of bigger armies, more lethal
weapons, and the speed and scope of belligerents’ response.
Thus, the Lieber Code drafted during our Civil War gave way
to the 1868 St. Petersburg Declaration, which stated that “the
progress of civilization should have the effect of alleviating as
much as possible the calamities of war.” Declaration
Renouncing the Use, in Time of War, of Certain Explosive
Projectiles (St. Petersburg Nov. 29/Dec. 11, 1868). The
                              15
Hague Convention of 1899 included the so-called Martens
Clause, still applicable today, which declared that except
where otherwise provided within the specific regulations of
the Convention, “populations and belligerents remain under
the protection and empire of the principles of international
law, as they result from the usages established between
civilized nations, from the laws of humanity, and the
requirements of the public conscience.” Convention with
Respect to the Laws and Customs of War on Land (Hague II),
pmbl., July 29, 1899. Thus, the international community
continues to recognize the protean nature of the law of war,
and recognizes that the law may and should develop to
address the demands of contemporary warfare.

     What is perhaps an ironic example of the fluid
development of the international law of war can be seen in
Hamdan v. Rumsfeld (Hamdan I), 548 U.S. 557 (2006). The
1907 Hague Convention and the Geneva Conventions which
followed it in 1929 and 1949 sought to provide a bright line of
demarcation between combatants who could be harmed and
noncombatants who could not be targeted. Reciprocity was
the key to this protective regime. Combatants had to act
under a fixed command structure, wear insignia that clearly
identified them as combatants, and refrain from targeting or
killing civilians. In 1977, the International Committee of the
Red Cross, egged on by non-aligned nations and those within
the sway of the former Soviet Union, introduced additional
protocols that broke away from the reciprocity norms,
allowing parties engaged in nonconventional warfare to refuse
to wear distinguishing insignia or carry arms openly until
immediately before an attack, and allowing non-state actors
“fighting against colonial domination and alien occupation
and against racist regimes” to assert lawful authority for their
efforts. Protocol Additional to the Geneva Conventions of 12
August 1949, art. 1, 44, June 8, 1977. Leading states,
                              16
including the United States, declined to ratify these protocols,
fearing they would protect terrorists at the expense of
civilians and allow insurgents to claim status as prisoners of
war.

     However, in Hamdan I, Justice Stevens broke apart these
carefully crafted understandings. He concluded that Salim
Hamdan was entitled to the protections of Article 3 of the
Geneva Conventions (Common Article 3) without
determining either the nature of the conflict or the status of
the combatant, and without deciding whether extending the
Conventions’ protections to terrorists, anarchists, or brigands
violated the expectation of the parties. Even Hamdan I’s fans
lament its “incomplete and at times cursory analysis of critical
issues involving the Geneva Conventions’ scope and the
substantive protections the Conventions provide.” Michael
W. Lewis, International Myopia: Hamdan’s Shortcut to
“Victory”, 42 U. RICH. L. REV. 687, 689 (2008). They note
“a certain clumsiness of application and a dearth of analytical
rigor.” Fionnuala Ní Aoláin, Hamdan and Common Article 3:
Did the Supreme Court Get It Right?, 91 MINN. L. REV. 1523,
1524 (2007).

     As Justice Stevens reconstructed Common Article 3,
plucking bits and pieces out of other articles to suit his
narrative, members of organizations that routinely target
civilians and exploit perfidious circumstances were given the
ability to argue for protections previously available only to
combatants who followed the rules. Detainees were quick to
take advantage of these opportunities. In Al Warafi v.
Obama, 716 F.3d 627 (D.C. Cir. 2013), a member of the
Taliban claimed protection as a medic under Article 24 of the
Geneva Convention despite the fact that he did not have the
mandatory insignia or identification the Convention requires.
Indeed, Al Warafi was captured carrying a weapon and had
                              17
previously served in a combat role. In Al-Bihani v. Obama,
590 F.3d 866, 871, 874 (D.C. Cir. 2010), a detained member
of al Qaeda argued he must be considered a civilian and
released because he did not belong to an official state military
and had not had the opportunity to commit a direct hostile act
such as firing a weapon in combat. Thus, belligerents who
did not play by the rules of international law sought to claim
the protections of that law. It is true that the purpose of the
Geneva Conventions is to protect human rights during
wartime—even the rights of combatants who flout the
Conventions—but it is hard to “reconcile this purpose with
the concept that a group which targets civilians may benefit
from that very behavior, by being afforded all the rights of the
civilians it targets.” Lewis, International Myopia, supra, at
714–15.

     In Hamdan I, the plurality seized upon the evolving
nature of the international law of war to extend the protections
of that law to nonconventional belligerents. But Bahlul
argues this court should refuse to allow the government to
leverage that evolving nature to deter those belligerents—an
approach that would handcuff the United States to a one-way
ratchet. Instead, we should recognize that the international
law of war also adapts in a way that allows states to oppose
nonconventional combatants and protect themselves from
terrorists.   Even more importantly, however, we must
acknowledge that the development of international law is a
task entrusted by the Framers to the legislative branch. The
judiciary must give Congress extraordinary deference when it
acts under its Define and Punish Clause powers.

                               B

     Under the approach to the Define and Punish Clause
outlined above, which gives proper regard to the dual
                               18
principles of flexibility and deference, the conspiracy charge
against Bahlul should stand.          Even if the offense of
conspiracy was not recognized under international law in
2001 by the same labels used by Congress in the 2006
Military Commissions Act, the substance is similar. Indeed, it
is to be expected that international law, which was largely
created by jurists trained in the civil law and which only more
recently has begun to absorb common law ideas and
institutions, differs formally from our own common law
tradition. See Colin B. Picker, International Law’s Mixed
Heritage: A Common/Civil Law Jurisdiction, 41 VAND. J.
TRANSNAT’L L. 1083, 1104–06 (2008). But that does not
mean that when Congress decides to implement international
law domestically it cannot adapt that law to fit within our
common law institutions. Such adaptation is appropriate both
because of the evolving nature of international law and the
necessities of implementing international law in an
established domestic legal system.            International law
recognizes analogues to conspiracy and other inchoate
offenses.

     In civil law countries, conspiracy is generally treated as a
mode of liability requiring a completed crime.              Peter
Margulies, Defining, Punishing, and Membership in the
Community of Nations: Material Support and Conspiracy
Charges in Military Commissions, 36 FORDHAM INT’L L.J. 1,
84 (2013). In the United States and other common law
countries, however, conspiracy is treated as a separate
offense, requiring only an agreement and, in some instances,
an overt act furthering the agreement. Id.; see, e.g., 18 U.S.C.
§ 371 (conspiracy to defraud the United States). International
law has adopted something of a hybrid approach, recognizing
conspiracy as a stand-alone offense for some of the most
serious war crimes—namely, genocide and waging aggressive
                                19
war—and using conspiracy as a mode of establishing liability
for all other international law offenses.

     With the exceptions of aggressive war and genocide,
international law does not recognize inchoate acts as stand-
alone offenses, but as modes of liability. For instance, the
Rome Statute recognizes that a person will be criminally
responsible for a crime if that person “[i]n any . . . way
contributes to the commission or attempted commission of
such a crime by a group of persons acting with a common
purpose.” Rome Statute of the International Criminal Court,
art. 25, § 3(d) (2002); see also id. § 3(b) (a person shall be
guilty of an offense if he “[o]rders, solicits or induces the
commission of such a crime which in fact occurs or is
attempted.”); id. § 3(c) (a person shall be guilty of an offense
if he “aids, abets or otherwise assists in its commission or its
attempted commission, including providing the means for its
commission.”). The difference between inchoate offenses
under domestic criminal law and the modes of liability under
international law is that international law requires that for
someone to be convicted of conspiracy, solicitation, or
material support, the substantive offense must have been
completed or attempted. But in defining the crime of
conspiracy as an inchoate offense, Congress exercised
precisely the kind of discretion and flexibility the Define and
Punish Clause envisions. Congress adapted recognized
international law to fit the country’s particular needs and legal
system. 3

3
  Even under the international law standard requiring a completed
offense, Bahlul was properly convicted. The conspiracy charge
alleges Bahlul conspired to commit various substantive offenses,
including murder of protected persons, attacking civilians and
civilian objects, murder in violation of the law of war, destruction
of property in violation of the law of war, terrorism, and providing
material support for terrorism. App. 120. The charge alleges
                                20

     It should be of no consequence that the form or name of
the charges was different from what might be charged in the
International Criminal Court or another international war
tribunal. Whether the prosecutor demonstrates a conspiracy
to obtain a conviction on a substantive offense, or establishes
a conspiracy to commit a completed act as a stand-alone
offense is a matter of form that springs from the differences
between common law and civil law institutions. In matching
military commission charges to international law offenses, we
should adopt a functional approach, looking at the conduct
involved rather than the label given to that conduct. It would
be senseless to limit military commissions’ ability to try
terrorists because the government has not adopted the forms
and names used by international tribunals. Under a functional
approach, Bahlul’s conviction for conspiracy is sufficiently
grounded in international law.

    Furthermore, recent international war crimes tribunals
have recognized as independent offenses conspiracy to
commit genocide and conspiracy to wage aggressive war. See
1 IMT 224–26 (recognizing the crime of conspiracy to wage
aggressive war but not recognizing conspiracy to commit war
crimes and crimes against humanity because the latter was not

Bahlul committed eleven overt acts in furtherance of that
conspiracy. Among other overt acts, the military commission
found Bahlul had prepared martyr wills “in preparation for the acts
of terrorism perpetrated by . . . Muhammed Atta, Ziad al Jarrah and
others at various locations in the United States on September 11,
2001” and “researched the economic effect of the September 11,
2001 attacks on the United States.” App. 122–23. Thus, the
military commission verdict incorporates the finding that Bahlul’s
co-conspirators completed international law offenses—namely, the
terrorist attacks of September 11. See Findings Worksheet, App.
130, 133.
                             21
defined as a separate crime in the Tribunal’s charter);
Updated Statute of the International Criminal Tribunal for the
Former Yugoslavia, art. 4 (2009) (making punishable
“conspiracy to commit genocide” as well as incitement or
attempt to commit genocide and complicity in genocide);
Statute, International Criminal Tribunal for Rwanda, art. 2
(2010) (same); Convention on the Prevention and Punishment
of the Crime of Genocide, art. 3 (1948) (same). These
offenses are the progeny of particular conflicts, created to
address new and previously unimaginable evils. Yet despite
the innovative and post hoc nature of these particular
conspiracy prosecutions, there was little if any protest that
they violated ex post facto principles—the abhorrent nature of
the offenses vitiated any such “justice” arguments. Similarly,
it may be the time has come for international law to recognize
the offense of conspiracy to commit acts of terrorism.
Terrorism may be the global security challenge of the 21st
Century, just like aggressive war was in the early 20th
Century and genocide was in the half century following
World War II. Perhaps the United States should be a leader in
this area—a leader in international law commensurate with its
status as a military leader in the war on terror—recognizing
the offense of conspiracy to commit acts of terrorism. These
are not questions for the judiciary, but rather for the
legislature to answer. And Congress did so with the MCA,
broadly construing international law to include the offense of
conspiracy.

                              C

     The Framers and subsequent courts recognized that to
define the law of nations, Congress required a zone of
deference. Without a measure of deference, legislative fear of
second-guessing would hobble Congress’s power under the
Define and Punish Clause, leaving the nation subject to the
                              22
fate Madison depicted for most previous democratic
experiments: “short in their lives . . . [and] violent in their
deaths.” THE FEDERALIST NO. 10, supra, at 76 (James
Madison). Contemporary international practice exhibits the
same kind of practical deference to permit individual states to
assess their own obligations.             The principle of
complementarity requires international tribunals to accord
deference to state investigations and recognizes that what is
mandated still leaves room for what is merely permissive.

     Hamdan I’s plurality had no trouble extending Common
Article 3 to members of organizations like al Qaeda. As
noted, by stretching Common Article 3 to meet what it clearly
perceived as a new exigency, the Court participated in the
law’s evolution. Thus, courts seem permitted to interpret
international conventions to allow the humanitarian aspect of
the law to evolve virtually instantaneously. We cannot, on the
other side of the equation, deny the political branches the
ability to respond to novel threats no matter how destructive,
and leave the nation at the mercy of an international
consensus and subject to the whims of hostile factions who
could prevent agreement or promote harmful agendas. See,
e.g., Protocol Additional to the Geneva Conventions of 12
August 1949, June 8, 1977. This cannot be the logical import
of arguing that the law of war is the law of nations. It would
make the Constitution a suicide pact; and the Define and
Punish Clause had just the opposite purpose.               For
international law to form a workable system, states need a
zone of deference. “Exercising judgment within this zone,
states could refine approaches that were broadly consistent
with established norms and also fostered global compliance.”
Margulies, Defining, Punishing, and Membership in the
Community of Nations, supra, at 16; cf. New State Ice Co. v.
Liebmann, 285 U.S. 262, 311 (1932) (Brandeis, J., dissenting)
                              23
(advocating deference to states, which serve as laboratories of
democracy).

     Of course, deference does not mean there are no limits.
We are always subject to the limits which restrain any regime
premised on natural law and dedicated to the protection of
natural rights.      This is likely what the international
community meant with the Martens Clause’s reference to the
“principles of international law” resulting from “the laws of
humanity[] and the requirements of the public conscience.”
Hague II, pmbl., July 29, 1899. But a one-sided rigidity
imposed on an inherently evolutionary international law does
not do justice, it thwarts it.

     Congress’s determination that conspiracy is an offense
against the law of nations constitutes a reasonable
interpretation of international law and is fully consistent with
that law. Therefore, the judiciary is bound to uphold
Congress’s exercise of authority under the Define and Punish
Clause.

                              IV

     Finally, I dissent with regard to the court’s remand of
residual issues to a panel of this court. Bahlul’s appeal has
been before this court nearly three years, and the court’s
decision ensures it will remain here at least another term.
Bahlul’s jury trial, equal protection, and freedom of speech
challenges are clearly meritless. I would deny them all
because Bahlul, as an alien located outside the territorial
United States, is not entitled to the protections of the
constitutional provisions he invokes, and, alternatively,
because his claims lack merit for the reasons stated by Judge
Kavanaugh. See Kavanaugh Op. Parts III, IV, and V.
However, to the extent the court was not ready to decide these
                              24
challenges, I would have asked the parties for supplemental
briefing so we could do so.

     More problematic, however, is that by reviewing Bahlul’s
retroactivity arguments under the plain error standard, the
court disposes of this case without providing the government
clear guidance for prosecuting the remaining detainees at
Guantanamo. Thus, it may be many years before the
government receives a definitive answer on whether it can
charge the September 11 perpetrators with conspiracy, or
whether Congress has the power to make such an offense
triable by military commission even prospectively. The
ability to charge conspiracy is an important prosecutorial tool
in the war on terror, where it can often be difficult for the
government to procure evidence directly connecting leaders
of militant groups with specific terror attacks.

    The United States is engaged in a war on terrorism. As
the various iterations of Hamdan and this case demonstrate,
the Executive Branch needs concrete guidance as to how it
can proceed with its prosecution of the September 11
conspirators and other detainees. Bahlul was first charged
before a military commission ten years ago. Today, this court
again leaves the government without any definitive answers.
The court does not express respect to the coordinate branches
of government by further delaying the executive’s
prosecutorial efforts and thwarting the legislative’s expressed
preference that detainees be tried by military commission. I
would resolve now the exceedingly important questions
presented in this case.

                            ***

    For these reasons, I would affirm Bahlul’s conspiracy
conviction and vacate his material support for terrorism and
                          25
solicitation convictions. I would remand to the Court of
Military Commission Review for it to address the
consequences of our decision for Bahlul’s life sentence.
     KAVANAUGH, Circuit Judge, concurring in the judgment
in part and dissenting in part: Of the seven judges on the en
banc Court for this case, five judges (all but Judge Henderson
and Judge Brown) agree in light of Boumediene v. Bush that
the Ex Post Facto Clause applies at Guantanamo. Indeed, the
Government concedes as much. Given the Government’s
concession, all seven judges on the en banc Court (including
Judge Henderson and Judge Brown) therefore apply the Ex
Post Facto Clause to analyze the offenses that were charged
against Bahlul under the Military Commissions Act of 2006.
In doing so, all seven judges reach the same bottom-line result
that the Court reached in Hamdan II (here, by virtue of the Ex
Post Facto Clause; there, by virtue of the 2006 Act as
informed by the Ex Post Facto Clause):              A military
commission may not try the offense of material support for
terrorism for conduct that occurred before enactment of the
2006 Act.1 All seven judges likewise conclude that a military
commission may not try the offense of solicitation for conduct
that occurred before enactment of the 2006 Act. The Court is
unanimous that those two offenses were not war crimes
triable by military commission at the time of Bahlul’s conduct
in 2001. Therefore, all seven judges agree that we must
vacate Bahlul’s material support for terrorism and solicitation
convictions as ex post facto violations.


     1
       So that there is no confusion as an historical matter and to be
clear about the legal implications of the majority opinion, it is
important to emphasize that the majority opinion’s analysis and
vacatur of Bahlul’s material support for terrorism conviction
necessarily mean that Salim Hamdan’s material support for
terrorism conviction likewise had to be vacated, which is what the
Hamdan II panel did. In other words, the majority opinion relies on
a slightly different rationale than did Hamdan II (the Ex Post Facto
Clause itself rather than the 2006 Act as informed by the Ex Post
Facto Clause), but the majority opinion reaches the same result:
The offense of material support for terrorism may not be tried by
military commission for conduct that occurred before the 2006 Act.
                                2
     As to conspiracy, six of the seven judges (all but Judge
Rogers) uphold Bahlul’s conspiracy conviction against his ex
post facto objection. Two of us (Judge Brown and I) would
do so by employing de novo review and concluding that
conspiracy, unlike material support for terrorism and
solicitation, has long been an offense triable by military
commission, including at the time of Bahlul’s conduct in
2001. The majority opinion likewise upholds Bahlul’s
conspiracy conviction but does so by employing plain error
review. The majority opinion believes that Bahlul forfeited
his ex post facto objection by not raising the objection at trial.

    I write separately to explain my analysis of these difficult
questions, in particular my analysis of the conspiracy issue.

     On September 11, 2001, Osama bin Laden learned the
results of al Qaeda’s attack on the United States by listening
to a radio. That radio was operated by bin Laden’s trusted
aide, Ali Hamza Ahmad Suliman al Bahlul. A native of
Yemen, Bahlul had moved to Afghanistan in the late 1990s to
join al Qaeda. Al Qaeda was and remains an international
organization whose stated goals are to drive the United States
from posts in the Middle East, to destroy the State of Israel,
and to dislodge moderate Islamic regimes and establish
radical Islamic control over the greater Middle East. To
advance its broad objectives, al Qaeda employs terrorist
attacks on civilian and military targets.

     After his arrival in Afghanistan in the late 1990s, Bahlul
became deeply embedded in al Qaeda’s operations. He
pledged allegiance to bin Laden. He trained at an al Qaeda
terrorist camp. He was appointed by bin Laden to lead al
Qaeda’s media and propaganda operation. Bahlul produced a
recruitment video glorifying al Qaeda’s October 2000
bombing of the U.S.S. Cole, an attack that killed 17
                                  3
Americans. Bahlul personally arranged the loyalty oath and
transcribed the “martyr will” of Mohammed Atta, Bahlul’s
one-time roommate and the hijacker who flew American
Airlines Flight 11 into the North Tower of the World Trade
Center on September 11th. Bahlul performed the same
services for Ziad Jarrah, another of Bahlul’s former
roommates, who hijacked and piloted United Airlines Flight
93, the flight that apparently was headed to destroy the U.S.
Capitol Building or the White House until it was downed in a
Pennsylvania field by American passengers who fought back.
Bahlul later said that he himself would have participated on
September 11th as hijacker number 20, but bin Laden deemed
his “media man” too essential to lose.

     By the time of the attacks on September 11, 2001, bin
Laden, Bahlul, and other senior al Qaeda leaders had already
evacuated from al Qaeda’s headquarters in Kandahar and
relocated to a remote mountainous region between Kabul and
Khost. Soon thereafter, Bahlul fled from Afghanistan to
Pakistan. In late 2001, while in Pakistan, he was captured.
Since 2002, he has been detained by the U.S. Military at the
U.S. Naval Base in Guantanamo pursuant to the 2001
Authorization for Use of Military Force. See Pub. L. No.
107-40, § 2(a), 115 Stat. 224, 224. The AUMF remains in
effect and authorizes the Government to detain enemy
combatants “for the duration of the relevant conflict” – in this
instance, the ongoing global war that the United States and its
allies are engaged in against al Qaeda and its associated
forces. Hamdi v. Rumsfeld, 542 U.S. 507, 521 (2004)
(controlling opinion of O’Connor, J.); see Uthman v. Obama,
637 F.3d 400, 402 (D.C. Cir. 2011).2

     2
       The ongoing global war against al Qaeda and its associated
forces is overlapping but distinct, in law and in fact, from the war in
Afghanistan against the former Taliban regime and Taliban forces.
                                4

     In addition to detaining Bahlul, the U.S. Government also
exercised its well-established authority to try him before a
military commission for war crimes. See 10 U.S.C. § 948d
(2006); 10 U.S.C. § 821 (2000); Hamdan v. Rumsfeld, 548
U.S. 557, 592-93 (2006); In re Yamashita, 327 U.S. 1, 7-8
(1946); Ex parte Quirin, 317 U.S. 1, 28 (1942). The
Government ultimately charged Bahlul with three offenses
specified in the Military Commissions Act of 2006:
conspiracy to commit war crimes, material support for
terrorism, and solicitation of war crimes. See Pub. L. No.
109-366, 120 Stat. 2600; 10 U.S.C. §§ 950u, 950v(b)(25),
950v(b)(28) (2006). Bahlul did not contest the relevant
factual allegations, but he vehemently objected to the
legitimacy of the military commission proceeding. The
military commission convicted Bahlul of all three offenses
and sentenced him to life in prison. The U.S. Court of
Military Commission Review affirmed. See United States v.
Bahlul, 820 F. Supp. 2d 1141 (C.M.C.R. 2011) (en banc).
Bahlul appealed to this Court, and we granted en banc review.

      Bahlul challenges his military commission convictions on
five distinct constitutional grounds: (i) the Article I Ex Post
Facto Clause, (ii) the Article I Define and Punish Clause,
(iii) the jury trial protections of Article III and the Fifth and
Sixth Amendments, (iv) the equal protection component of
the Due Process Clause of the Fifth Amendment, and (v) the
free speech protections of the First Amendment.

     With respect to his material support for terrorism and
solicitation convictions, Bahlul’s Ex Post Facto Clause


The potential end of the U.S. combat mission against Taliban forces
in Afghanistan obviously does not mean the end of the global war
against al Qaeda and its associated forces.
                              5
argument is correct because those offenses were not war
crimes triable by military commission at the time of Bahlul’s
conduct in 2001. With respect to his conspiracy conviction,
however, Bahlul’s Ex Post Facto Clause challenge lacks merit
because conspiracy has long been proscribed under U.S. law
as a war crime triable by military commission, including at
the time of Bahlul’s conduct. Bahlul’s other arguments are all
unavailing. Therefore, I would affirm Bahlul’s conspiracy
conviction, vacate his material support for terrorism and
solicitation convictions as ex post facto violations, and
remand to the U.S. Court of Military Commission Review for
it to address the consequences, if any, for Bahlul’s life
sentence.

                               I

     Bahlul’s primary argument to this Court rests on the Ex
Post Facto Clause of Article I, Section 9 of the Constitution.
See U.S. CONST. art. I, § 9, cl. 3 (“No Bill of Attainder or ex
post facto Law shall be passed.”). Among other things, the
Ex Post Facto Clause bars retroactive prosecution of new
offenses. See Peugh v. United States, 133 S. Ct. 2072, 2081
(2013); Collins v. Youngblood, 497 U.S. 37, 42-43, 52 (1990).
Bahlul contends that (i) the Ex Post Facto Clause applies to
military commissions at Guantanamo and (ii) the three
offenses in the 2006 Act that were charged against him –
conspiracy to commit war crimes, material support for
terrorism, and solicitation of war crimes – were new offenses
that were not triable by military commission at the time of his
conduct back in 2001.

   In response, the Government concedes (correctly) that the
Ex Post Facto Clause applies to military commissions at
Guantanamo. Cf. Boumediene v. Bush, 553 U.S. 723, 766-71
                                  6
(2008).3 And the Government all but concedes (again
correctly) that material support for terrorism and solicitation

     3
        As a general matter, the U.S. Constitution applies to U.S.
citizens worldwide and to non-U.S. citizens within the 50 states and
the District of Columbia, but not to non-U.S. citizens in foreign
countries. See Zadvydas v. Davis, 533 U.S. 678, 693 (2001);
United States v. Verdugo-Urquidez, 494 U.S. 259, 264-75 (1990);
id. at 275-78 (Kennedy, J., concurring); Reid v. Covert, 354 U.S. 1,
5-14 (1957) (plurality opinion); Johnson v. Eisentrager, 339 U.S.
763, 768-85 (1950).
      A more nuanced issue is the reach of the Constitution to non-
U.S. citizens in an in-between category: in territories owned or
controlled by the United States, such as Puerto Rico and Guam.
Determining whether the Constitution applies to non-U.S. citizens
in U.S. territories requires a “functional” rather than “formalistic”
analysis of the particular constitutional provision and the particular
territory at issue. Boumediene v. Bush, 553 U.S. 723, 762, 764
(2008). The Court focuses on whether it would be “impracticable
and anomalous” to extend the constitutional guarantee in question
to non-U.S. citizens in the territory at issue. Id. at 759 (quoting
Reid v. Covert, 354 U.S. 1, 74 (1957) (Harlan, J., concurring)); see
Balzac v. Porto Rico, 258 U.S. 298 (1922) (Puerto Rico); Dorr v.
United States, 195 U.S. 138 (1904) (U.S.-occupied Philippines);
Hawaii v. Mankichi, 190 U.S. 197 (1903) (pre-statehood Hawaii).
      In Boumediene, the Court determined that Guantanamo was de
facto U.S. territory – akin to Puerto Rico, for example – and not
foreign territory. See 553 U.S. at 769 (“In every practical sense
Guantanamo is not abroad; it is within the constant jurisdiction of
the United States.”); compare Eisentrager, 339 U.S. at 777-81
(habeas corpus right does not extend to U.S.-controlled military
prison in post-World War II Germany); Al Maqaleh v. Hagel, 738
F.3d 312, 317 (D.C. Cir. 2013) (habeas corpus right does not
extend to U.S. military base in wartime Afghanistan). The Court
then determined that it would not be “impracticable or anomalous”
to extend the habeas corpus right to non-U.S. citizen detainees at
Guantanamo. See Boumediene, 553 U.S. at 769-71. As the
Government concedes, the Boumediene analysis leads inexorably to
                                 7
were new offenses that were not triable by military
commission back in 2001. See Hamdan v. United States, 696
F.3d 1238, 1252 (D.C. Cir. 2012) (Hamdan II). But the
Government forcefully argues that one of the three offenses
charged against Bahlul, conspiracy, was not a new offense.
According to the Government, conspiracy has long been
triable by military commission under U.S. law, including at
the time of Bahlul’s conduct.

     The relevant military commission law in effect at the
time of Bahlul’s conduct was 10 U.S.C. § 821. That statute
was first enacted in 1916 and then re-enacted in 1950 as part
of the Uniform Code of Military Justice. See Pub. L. No. 81-
506, 64 Stat. 107, 115 (1950); Pub. L. No. 64-242, 39 Stat.
619, 653 (1916). As of 2001, at the time of Bahlul’s conduct,
Section 821 provided 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
     commissions, provost courts, or other military tribunals.

10 U.S.C. § 821 (2000) (emphasis added).

    As the Deputy Solicitor General aptly stated at oral
argument, the question at the heart of this case is whether, as
of 2001, conspiracy to commit war crimes was an offense
proscribed under the “law of war” prong of Section 821. See


the conclusion that the ex post facto right applies at Guantanamo.
It would be no more impracticable or anomalous to apply the
Article I, Section 9 ex post facto right at Guantanamo than it is to
apply the Article I, Section 9 habeas corpus right at Guantanamo.
                              8
Tr. of Oral Arg. at 15-20. The Supreme Court faced that
exact same question in Hamdan v. Rumsfeld, 548 U.S. 557
(2006). The Court as a whole did not decide the issue
because it was not necessary to do so given the Court’s
conclusion that the military commissions then in place were
unlawful on certain procedural grounds. As a result, there is
no binding precedent from that case on the conspiracy issue.
But seven Justices opined on the conspiracy question and split
4-3 in contrasting opinions written by Justice Stevens and
Justice Thomas. (Justice Kennedy did not address the
conspiracy charge. Chief Justice Roberts did not take part in
the case.)      Justice Stevens’s opinion concluded that
conspiracy was not a law of war offense under Section 821.
See 548 U.S. at 600-12. Justice Thomas’s opinion concluded
that conspiracy was a law of war offense under Section 821.
See id. at 697-706.

     Importantly for our purposes as a lower court, all seven
Justices who addressed the Section 821 “law of war” issue in
Hamdan agreed that it turned on the content of the “common
law of war” and required careful evaluation of historical U.S.
military commission precedents involving conspiracy. Id. at
602 (Stevens, J.); id. at 689 (Thomas, J.). Although the two
opinions reached different answers, they considered the same
basic question: Did the U.S. military commission precedents
suffice to show that conspiracy was a law of war offense
triable by military commission under Section 821?

     The detailed historical inquiry undertaken by the seven
Justices in Hamdan was not idle background discussion. On
the contrary, the historical inquiry followed from the text of
Section 821. Enacted in 1916 when Congress amended the
Articles of War and set forth new rules for courts-martial, and
then re-enacted in 1950 as part of the Uniform Code of
Military Justice, Section 821 provided that the new rules
                                 9
governing courts-martial did not “deprive” military
commissions of their pre-existing authority. 10 U.S.C. § 821
(2000).4 Notwithstanding Section 821’s somewhat unusual
negative phrasing, the Supreme Court has repeatedly
interpreted Section 821 as affirmative statutory authorization
for the Executive Branch to convene military commissions to
try war crimes. See Hamdan, 548 U.S. at 592; In re
Yamashita, 327 U.S. 1, 7-8 (1946); Ex parte Quirin, 317 U.S.
1, 28 (1942). With its reference to statutory offenses, Section
821 authorizes military commissions to try offenses such as
spying and aiding the enemy that are triable by military
commission under federal statute. See 10 U.S.C. §§ 904, 906
(2000); Quirin, 317 U.S. at 41-42. With its reference to the
“law of war,” a term that encompasses the international law of
war, Section 821 authorizes military commissions to try
offenses that are war crimes under international law. See
Yamashita, 327 U.S. at 7, 14-16. Moreover, as the seven
Justices in Hamdan recognized with their extensive focus on
U.S. military commission precedents – and as the Supreme
Court stated in Madsen v. Kinsella in 1952 and Yamashita in
1946 – Section 821’s “law of war” prong also expressly
preserved the authority of military commissions to try
offenses that had traditionally been tried by U.S. military
commissions as of 1916 and 1950. See Madsen v. Kinsella,
343 U.S. 341, 352 (1952) (statute “states unequivocally that
Congress has not deprived such commissions or tribunals of

    4
       The precise text of Section 821 and its predecessor statutes
has varied slightly over time, but the anti-deprivation language has
been present in every iteration. See Pub. L. No. 64-242, 39 Stat.
619, 653 (1916) (“shall not be construed as depriving military
commissions”); Pub. L. No. 66-242; 41 Stat. 759, 790 (1920)
(“shall not be construed as depriving military commissions”); Pub.
L. No. 81-506, 64 Stat. 107, 115 (1950) (“shall not be construed as
depriving military commissions”); Pub. L. No. 84-1028, 70A Stat.
1, 44 (1956) (“do not deprive military commissions”).
                              10
the existing jurisdiction which they had over such offenders
and offenses as of August 29, 1916”); Yamashita, 327 U.S. at
20 (statute authorized military commissions “to preserve their
traditional jurisdiction over enemy combatants”); cf. Sekhar v.
United States, 133 S. Ct. 2720, 2724 (2013) (when “a word is
obviously transplanted from another legal source, whether the
common law or other legislation, it brings the old soil with
it”) (internal quotation mark omitted).

     Bahlul nevertheless argues that the phrase “law of war”
in Section 821 encompasses only international law offenses
and not those offenses traditionally triable by U.S. military
commissions. In other words, Bahlul says that Section 821,
although expressly crafted not to “deprive” U.S. military
commissions of their existing common-law authority over
conspiracy and other offenses, did in fact deprive military
commissions of that authority for offenses that were not also
proscribed by the international law of war.

     Bahlul’s argument that Section 821’s “law of war” prong
consists exclusively of international law offenses is
inconsistent with the text and textually stated purpose of
Section 821, as well as with Supreme Court precedents such
as Madsen and Yamashita interpreting Section 821. Perhaps
most tellingly for present purposes, Bahlul’s interpretation of
Section 821 conflicts with what the Supreme Court actually
did in Hamdan. Seven Justices in Hamdan analyzed the “law
of war” embodied in Section 821 as the international law of
war supplemented by established U.S. military commission
precedents. Indeed, that is the only interpretation of Section
821 that squares with how the seven Justices analyzed the
question in Hamdan.

    In short, at the time of Bahlul’s conduct, Section 821
authorized military commissions to try offenses drawn from
                                 11
three bodies of law: federal statutes defining offenses triable
by military commission, the international law of war, and
historical U.S. military commission tradition and practice as
preserved by Congress when it enacted Section 821 in 1916
and 1950.5

     At the time of Bahlul’s conduct, neither any federal
statute nor the international law of war proscribed conspiracy
as a war crime triable by military commission. So the
question we must decide is whether U.S. military commission
precedents treated conspiracy as an offense triable by military
commission. In other words, we must decide the question that
was addressed by seven Justices in Hamdan but not decided
by the Court. The answer, in my view, is yes: U.S. military
commission precedents have treated conspiracy as an offense
triable by military commission.

     I base that conclusion in substantial part on the 1865
military commission conviction of the conspirators who
    5
       A passage in this Court’s decision in Hamdan II – a passage
beginning “Third,” in the third-to-last paragraph of the opinion –
suggested that the phrase “law of war” in Section 821 encompassed
offenses under the international law of war but did not cover other
offenses that were rooted only in U.S. military commission
precedents. See Hamdan v. United States, 696 F.3d 1238, 1252
(D.C. Cir. 2012) (Hamdan II). That statement was not necessary to
the result in Hamdan II because, as the opinion explained, material
support for terrorism was not an offense under the international law
of war or under U.S. military commission precedents. See id. In
any event, as the Deputy Solicitor General persuasively explained
at oral argument, see Tr. of Oral Arg. at 15-20, that statement in
Hamdan II was underinclusive. Given the text and textually stated
purpose of Section 821, and the relevant Supreme Court precedents,
the “law of war” prong of Section 821 covers both offenses under
the international law of war and offenses sufficiently rooted in U.S.
military commission precedents.
                              12
plotted to assassinate President Lincoln. Put simply, the
military commission trial of the Lincoln conspirators is the
highest-profile and most important U.S. military commission
precedent in American history. President Andrew Johnson,
after seeking the advice of the Attorney General, decided to
try the Lincoln conspirators by military commission for
violating the law of war rather than by criminal trial in
civilian court. See Military Commissions, 11 Op. Attorney
Gen. 297 (1865); see also Ex parte Mudd, 17 F. Cas. 954
(S.D. Fla. 1868). The Lincoln conspirators were expressly
charged with and convicted of conspiracy – in that case,
conspiracy to violate the law of war by killing the President
and Commander in Chief of the Union Army, Abraham
Lincoln. Indeed, conspiracy was the only offense charged
against them. After an extensive multi-week trial and
vigorous argument about the facts and the commission’s
jurisdiction, numerous conspirators were convicted, and
several of them were sentenced to death and executed.

     In considering the history of U.S. military commissions,
particularly at the time of Section 821’s original enactment in
1916 and its re-enactment in 1950, the Lincoln conspirators
case looms as an especially clear and significant precedent.

     The Lincoln conspirators precedent does not stand alone.
The second highest-profile and second most important U.S.
military commission in American history was the military
commission trial of the Nazi saboteurs who secretly crossed
into the United States during World War II. Again, the
defendants were expressly charged with and convicted of
conspiracy, as well as of another law of war offense. The
Attorney General of the United States personally prosecuted
the case before the military commission. President Franklin
Roosevelt, the Commander in Chief of the Army and Navy,
reviewed and affirmed all of the convictions. Upon its
                             13
review, the Supreme Court affirmed the saboteurs’
convictions based on the other law of war offense, making it
unnecessary to address conspiracy. See Quirin, 317 U.S. at
46. Like the Lincoln conspiracy precedent, the trial of the
Nazi saboteurs still stands as a major precedent in which a
U.S. military commission charged and convicted the
defendants of conspiracy.

     To summarize so far: As of 1950 when Congress re-
enacted Section 821 as part of the Uniform Code of Military
Justice and expressly preserved the traditional authority of
U.S. military commissions, the two most well-known and
important U.S. military commissions in American history
tried and convicted the defendants of conspiracy.

     And there were other significant precedents as well. For
example, later in World War II, the Government prosecuted
another set of Nazi saboteurs by military commission for
conspiracy. In that case, Assistant Attorney General Tom
Clark produced a formal memorandum concluding – based in
large part on the precedents involving the Lincoln
conspirators and the earlier Nazi saboteurs – that conspiracy
was a law of war offense triable by military commission. See
Memorandum from Tom C. Clark, Assistant Attorney
General, to Myron C. Kramer, Judge Advocate General (Mar.
12, 1945), reprinted in U.S. Supp. App. 133-139. The
military commission subsequently convicted the defendants of
conspiracy. President Truman reviewed and affirmed the
convictions. And after one of those Nazi saboteurs later
challenged his conviction in court, the Tenth Circuit upheld
the conviction, including the conspiracy conviction, in an
opinion by Judge Murrah. See Colepaugh v. Looney, 235
F.2d 429 (10th Cir. 1956).
                              14
     To be sure, against those landmark American precedents,
some international tribunals and conventions subsequent to
the original enactment of Section 821 have chosen not to
make conspiracy a war crime triable by military commission.
Most notably, the International Military Tribunal at
Nuremberg did not identify conspiracy to commit war crimes
as an offense triable before that Tribunal. But the Tribunal
reached that conclusion over the objections of the American
prosecution team led by Justice Robert Jackson, and the
Tribunal did so in part because conspiracy was not recognized
by European law. See Hamdan, 548 U.S. at 611 (Stevens, J.);
id. at 702 n.14 (Thomas, J.).

      In any event, what matters for present purposes is that at
the time of Bahlul’s conduct, no authoritative source of U.S.
law had ever negated the validity or authority of the U.S.
military commission convictions of the Lincoln assassins for
conspiracy or of the Nazi saboteurs for conspiracy. In 1916,
when it enacted Section 821, as well as in 1950 when it re-
enacted the statute, Congress was aware of those significant
precedents. See id. at 592 & n.22 (majority opinion)
(recounting legislative history of 1950 enactment and noting
Congress’s awareness of Quirin precedent); Madsen, 343 U.S.
at 353 & n.20 (recounting legislative history of 1916
enactment, including discussion of Civil War, Mexican-
American War, and Spanish-American War precedents); A
Bill to Unify, Consolidate, Revise, and Codify the Articles of
War, Hearing on H.R. 2498: Before Subcommittee No. 1 of
the House Committee on Armed Services, 81st Cong. 962
(1949) (“A classical example of the military tribunal is the
trial of the Lincoln conspirators.”) (testimony of Colonel John
P. Dinsmore); see also Trials by Courts-Martial: Hearing on
S. 5320 Before the Senate Committee on Military Affairs, 65th
Cong. 279 (1919) (Judge Advocate General Enoch H.
Crowder discussing Lincoln conspirators trial). Moreover,
                              15
the leading authority on military commissions at the time of
both enactments, Colonel William Winthrop’s treatise on
military law, repeatedly referenced the Lincoln conspirators
precedent. See WILLIAM WINTHROP, MILITARY LAW AND
PRECEDENTS 167, 169, 185 n.38, 334 n.40, 834 & n.77, 836
n.90, 839 n.5 (rev. 2d ed. 1920).

     By stating that Section 821 did not “deprive” military
commissions of their traditional authority, Congress
necessarily incorporated the Lincoln assassins precedent for
conspiracy when it enacted the original version of Section 821
in 1916, and it incorporated the Lincoln assassins and Nazi
saboteur precedents for conspiracy when it re-enacted the
statute in 1950 as part of the Uniform Code of Military
Justice. After all, it would be rather bizarre to conclude that
Congress, by enacting a statute that said it did not “deprive”
military commissions of their traditional authority, in fact
silently overruled the two most significant and well-known
military commission precedents in American history. Since
1950, moreover, Congress has never backed away from its
express preservation of traditional U.S. military commission
authority over conspiracy. Indeed, in the 2006 Act, Congress
reiterated its longstanding intent and belief that conspiracy
has “traditionally been triable by military commissions.” 10
U.S.C. § 950p(a) (2006).

     At the time of Bahlul’s conduct, the other two Branches
likewise had never undermined the validity of the Lincoln
conspirators and Nazi saboteur precedents. No U.S. court had
ever cast any doubt on those landmark military commission
convictions, or on trying conspiracy by military commission.
And in the Executive Branch, there is a straight line from now
to then: In deciding that conspiracy is an offense that may be
tried by military commission, President Barack Obama is the
same as President George W. Bush is the same as President
                                 16
Harry Truman is the same as President Franklin Roosevelt is
the same as President Andrew Johnson is the same as
President Abraham Lincoln.

     In light of the clear and consistent historical record in the
United States as of the time of Bahlul’s conduct in 2001 – in
all three Branches of the U.S. Government – it is ultimately
not persuasive to say, as Bahlul does, that conspiracy was a
brand new U.S. military commission offense created by the
2006 Act. If we indulge the idea that Bahlul, holed up with
bin Laden somewhere in the hills of Afghanistan, consulted
U.S. military commission law on conspiracy back in 2001, he
would have readily found the two most well-known U.S.
military commission precedents, the landmark Lincoln
assassin and Nazi saboteur cases in which the defendants had
been convicted of conspiracy.

     In sum, conspiracy was triable by military commission
under the law of war prong of Section 821 at the time of
Bahlul’s conduct in 2001. The Ex Post Facto Clause
therefore does not bar the Government’s prosecution of
Bahlul under the 2006 Act for conspiracy. And for that same
reason, to the extent that Bahlul argues that the 2006 Act itself
incorporates ex post facto principles and bars retroactive
prosecution of new offenses, the 2006 Act likewise does not
bar the Government’s prosecution of Bahlul for conspiracy.6

    6
       It would be unconstitutional to apply any new offenses in the
2006 Act to pre-2006 conduct. In light of the canon of
constitutional avoidance and Congress’s express statement in the
text of the 2006 Act that the law did “not establish new crimes,” but
rather merely codified “offenses that have traditionally been triable
by military commissions,” I read the 2006 Act consistently with the
Ex Post Facto Clause to authorize retroactive prosecution only of
offenses that were already prohibited as war crimes triable by
military commission under U.S. law at the time of the defendant’s
                                 17

     By contrast, as the Government all but concedes, there is
no historical U.S. military commission precedent for trying
the offenses of material support for terrorism and solicitation
before U.S. military commissions. And those two offenses
are not international law of war offenses, nor were they triable
by military commission under any other federal statute at the
time of Bahlul’s conduct. The Government’s actions between
the attacks of September 11, 2001, and the enactment of the
2006 Act underscore that material support for terrorism and
solicitation have not been thought to be Section 821 “law of
war” offenses. During that time, the United States charged 10
al Qaeda defendants before military commissions. The
United States did not charge any of them with material
support for terrorism or solicitation, presumably because it
was widely understood that those two offenses were not
covered under Section 821. By contrast, the United States
charged all 10 al Qaeda defendants with conspiracy,
presumably because the Government believed, based on the

conduct. 10 U.S.C. § 950p(a) (2006); see Hamdan v. United States,
696 F.3d 1238, 1247 (D.C. Cir. 2012) (Hamdan II); cf. Bond v.
United States, 134 S. Ct. 2077, 2087-90 (2014); Northwest Austin
Municipal Utility District Number One v. Holder, 557 U.S. 193,
205 (2009); Blodgett v. Holden, 275 U.S. 142, 148 (1927) (Holmes,
J., concurring) (“as between two possible interpretations of a
statute, by one of which it would be unconstitutional and by the
other valid, our plain duty is to adopt that which will save the
Act.”). The majority opinion disagrees that the 2006 Act can be
read to incorporate ex post facto principles, even in light of the
constitutional avoidance canon. I do not think the majority opinion
is correct about that. But that does not matter in this case. Whether
it is because of the Act as construed in light of the Ex Post Facto
Clause or because of the Ex Post Facto Clause itself (or both),
military commissions at Guantanamo may not prosecute any new
offenses in the 2006 Act for pre-2006 conduct. The key question is
which offenses in the 2006 Act are new.
                              18
historical precedents, that conspiracy was covered under
Section 821.

    In short, unlike conspiracy, material support for terrorism
and solicitation were not covered under Section 821 at the
time of Bahlul’s conduct in 2001. See Hamdan II, 696 F.3d at
1252 (concluding that material support for terrorism was not
covered under Section 821). Bahlul’s convictions for material
support for terrorism and solicitation therefore must be
vacated as ex post facto violations.

                              II

     In challenging his convictions, Bahlul also advances a far
more sweeping constitutional argument. He contends that
Congress lacks constitutional authority to make conspiracy,
material support for terrorism, or solicitation war crimes
triable by military commissions, even prospectively, because
those offenses are not proscribed under the international law
of war. Bahlul’s argument, in essence, is that the U.S.
Constitution (as relevant here) incorporates international law
and thereby interposes international law as a constitutional
constraint on what crimes Congress may make triable by
military commission. On its face, that is an extraordinary
argument that would, as a matter of U.S. constitutional law,
subordinate the U.S. Congress and the U.S. President to the
dictates of the international community – a community that at
any given time could be unsupportive of or even hostile to
U.S. national security interests as defined by Congress and the
President. And because conspiracy is not and has not been an
offense under the international law of war, the argument
would render the Lincoln conspirators and Nazi saboteur
convictions for conspiracy illegitimate and unconstitutional. I
would reject the argument.
                                 19
     Bahlul spins out the argument in two different ways.
First, he contends that Congress’s authority to create offenses
triable by military commission stems exclusively from the
Article I Define and Punish Clause, which allegedly confines
military commissions to trying only international law of war
offenses. I will consider that argument in this Part II of the
opinion.     Second, Bahlul contends that the jury trial
protections of Article III and the Fifth and Sixth Amendments
generally require jury trials, and that the exception to those
jury trial protections for military commissions applies only to
international law of war offenses. I will consider that
argument in Part III below.7

    Bahlul says that Congress may enact offenses triable by
U.S. military commissions only under Congress’s Article I,
Section 8 power to “define and punish . . . Offences against
the Law of Nations.” U.S. CONST. art. I, § 8, cl. 10. Because
conspiracy is not an offense under international law, Bahlul
argues that Congress lacked power under Article I, Section 8
to make the offense triable by military commission.

     The premise of this argument is incorrect. As the
Supreme Court has repeatedly stated, Congress’s authority to
establish military commissions to try war crimes does not
arise exclusively from the Define and Punish Clause. On the
contrary, as the Supreme Court has explained, Congress also
has authority to establish military commissions to try war

     7
      For purposes of Bahlul’s jury trial, equal protection, and First
Amendment arguments, I will assume for the sake of argument that
those constitutional protections apply to non-U.S.-citizens at
Guantanamo. See supra note 3; Kiyemba v. Obama, 561 F.3d 509,
518 n.4 (D.C. Cir. 2009) (Kavanaugh, J., concurring) (similarly
assuming for sake of argument that Due Process Clause applies to
Guantanamo). Even so, as I will explain, Bahlul’s arguments are
unavailing.
                              20
crimes under the Declare War and Necessary and Proper
Clauses of Article I, Section 8. See U.S. CONST. art. I, § 8,
cls. 11, 18; Hamdan v. Rumsfeld, 548 U.S. 557, 591-92 &
n.21 (2006); Madsen v. Kinsella, 343 U.S. 341, 346 n.9
(1952); Ex parte Quirin, 317 U.S. 1, 26-31 (1942); see also
WILLIAM WINTHROP, MILITARY LAW AND PRECEDENTS 831
(rev. 2d ed. 1920) (military commission “is simply an
instrumentality for the more efficient execution of the war
powers vested in Congress and the power vested in the
President as Commander-in-chief in war”). And unlike the
Define and Punish Clause, the Declare War Clause and the
other Article I war powers clauses do not refer to international
law and are not defined or constrained by international law.
In other words, at least as a matter of U.S. constitutional law
(as distinct from international law), the United States is not
subject to the whims or dictates of the international
community when the United States exercises its war powers.
Therefore, under the text of Article I, international law is not
a constitutional constraint when Congress proscribes war
crimes triable by military commission.

     That interpretation also follows from historical practice.
In accordance with the constitutional text, Congress since the
earliest days of the Republic has gone beyond international
law in proscribing war crimes triable by military commission.
See 10 U.S.C. §§ 950t(26), 950t(27) (2012) (aiding the enemy
and spying); 10 U.S.C. §§ 904, 906 (2000) (same); Articles of
War of 1806, 2 Stat. 359, 366, 371 (1806) (same). That
historical practice strongly supports the conclusion that
international law is not a constitutional constraint when
Congress proscribes war crimes triable by military
commission. Cf. NLRB v. Noel Canning, No. 12-1281 (U.S.
June 26, 2014) (relying on longstanding historical practice to
interpret Constitution).
                                21
     And perhaps most important for us as a lower court is the
Supreme Court’s decision in Quirin. There, the Court
rejected various constitutional challenges to military
commissions. In so doing, the Court emphasized among other
things that U.S. military commissions have long possessed
statutory authority to try the offense of spying, which was not
and has never been an offense under the international law of
war. See Quirin, 317 U.S. at 41-42; see also U.S. Br. 71
(spying not an international law of war offense); National
Institute of Military Justice Amicus Br. 18 n.8 (same);
Hamdan v. United States, 696 F.3d 1238, 1246 n.6 (D.C. Cir.
2012) (Hamdan II) (Kavanaugh, J., concurring) (same).
Quirin’s approval of spying, a non-international-law-of-war
offense, as an offense triable by military commission
confirms that Congress has authority under the Constitution to
make non-international-law-of-war crimes triable by military
commission.

     In short, the constitutional text, longstanding statutes, and
Supreme Court precedent all demonstrate that Article I does
not limit Congress to international law of war offenses when
it proscribes war crimes triable by military commission.

                                III

     Citing the jury trial protections of Article III and the Fifth
and Sixth Amendments, Bahlul reprises the same basic
argument that U.S. military commissions may try only
international law of war offenses. This version of Bahlul’s
argument begins with the premise that the Constitution
requires all crimes to be tried by jury. Bahlul recognizes, as
he must, that the Supreme Court in Quirin nonetheless
permitted trial by military commission for war crimes. See Ex
parte Quirin, 317 U.S. 1, 38-45 (1942); see also Hamdan v.
Rumsfeld, 548 U.S. 557, 592-93 (2006). But Bahlul says that
                               22
this exception to the jury trial right extends only to
international law of war offenses.

    To begin with, there is no textual support for Bahlul’s
theory. There is no textual reason to think that the exception
to the jury trial protections for military commissions is
somehow confined to international law of war offenses. That
exception, as the Supreme Court has explained, stems from
the various war powers clauses in Article I and Article II.
And those war powers clauses are not defined or constrained
by international law. See Hamdan, 548 U.S. at 591-92;
Quirin, 317 U.S. at 25-27.

     Moreover, Bahlul’s novel theory contravenes precedent:
It is inconsistent with the Lincoln conspirators and Nazi
saboteurs conspiracy convictions, and it cannot be squared
with Quirin.

     In Quirin, the defendants argued that they had a
constitutional right to trial by jury and thus could not be tried
by military commission. At some length, the Court in Quirin
specifically rejected the defendants’ Article III and Fifth and
Sixth Amendment jury trial objections to trial by military
commission. See Quirin, 317 U.S. at 38-45. The Court
explained that the Constitution’s jury trial provisions “did not
enlarge the right to jury trial” beyond the right as it existed at
common law. Id. at 39. Because the common law did not
preclude military commission trials, “Article III and the Fifth
and Sixth Amendments cannot be taken to have extended the
right to demand a jury to trials by military commission.” Id.
at 40.

    For present purposes, two things are notable about
Quirin. First, in reaching its conclusion on the jury trial issue,
the Court relied on the fact that Congress had made spying an
                               23
offense triable by military commission since the earliest days
of the Republic. The Court said that the early Congress’s
enactment of the spying statute “must be regarded as a
contemporary construction” of both Article III and the Fifth
and Sixth Amendments “as not foreclosing trial by military
tribunals, without a jury, of offenses against the law of war
committed by enemies not in or associated with our Armed
Forces.” Id. at 41. “Such a construction,” the Court said, “is
entitled to the greatest respect.” Id. at 41-42. To reiterate, the
offense of spying on which the Court relied was not and has
never been an offense under the international law of war. It
thus makes little sense to read Quirin as barring military
commission trial of non-international-law-of-war offenses
when Quirin, in rejecting a jury trial objection to military
commissions, relied expressly on a longstanding statute
making a non-international-law-of-war offense triable by
military commission. Second, nothing about the Court’s
reasoning in Quirin on this point depended on whether the
offense tried before a military commission was an
international law of war offense or, by contrast, was a military
commission offense recognized only by U.S. law. In other
words, the Court never stated that military commissions are
constitutionally permitted only for international law of war
offenses, which one would have expected the Court to say if
the Court believed that military commissions are
constitutionally permitted only for international law of war
offenses.

     In short, neither Article I nor the jury trial protections of
Article III and the Fifth and Sixth Amendments limit
Congress to the international law of war when Congress
proscribes war crimes triable by military commission. Put
another way, the United States may be a leader in the
international community, not just a follower, when Congress
authorizes war against a terrorist organization or makes
                               24
crimes such as conspiracy war crimes triable by military
commission. To be sure, it can be quite prudent (and in some
circumstances required as a matter of international law) for
Congress and the President to coordinate closely with the
international community and to pay careful attention to
international law when authorizing war and enacting war
crimes triable by military commission. But those policy
factors, political realities, and international law considerations
are not constitutional constraints incorporated into the Article
I war powers clauses or the jury trial guarantees of Article III
and the Fifth and Sixth Amendments.

                               IV

     Bahlul also raises an equal protection challenge under the
Due Process Clause of the Fifth Amendment. Bahlul argues
that the Military Commissions Act of 2006 violated equal
protection principles because it was underinclusive in
authorizing military commission trials of alien enemy
combatants but not of U.S. citizen enemy combatants. See 10
U.S.C. §§ 948b(a), 948c, 948d(a) (2006); Bolling v. Sharpe,
347 U.S. 497, 499 (1954) (Fifth Amendment includes equal
protection component). That argument is meritless.

     The Government correctly points out that many federal
laws draw distinctions between U.S. citizens and aliens, and
that the Supreme Court has upheld many such laws. See, e.g.,
Demore v. Kim, 538 U.S. 510, 522 (2003); Mathews v. Diaz,
426 U.S. 67, 78-80 (1976); see also Bluman v. FEC, 800 F.
Supp. 2d 281, 287 (D.D.C. 2011), affirmed, 132 S. Ct. 1087
(2012). The Supreme Court has explained that any federal
“policy toward aliens is vitally and intricately interwoven
with contemporaneous policies in regard to the conduct of
foreign relations, the war power, and the maintenance of a
republican form of government” and that such “matters are so
                               25
exclusively entrusted to the political branches of government
as to be largely immune from judicial inquiry or interference.”
Mathews, 426 U.S. at 81 n.17 (quoting Harisiades v.
Shaughnessy, 342 U.S. 580, 588-89 (1952)). As a result,
federal laws drawing distinctions between U.S. citizens and
aliens – particularly in the context of war and national
security – are generally permissible so long as they are
rationally related to a legitimate governmental interest. See
Demore, 538 U.S. at 527-28; Mathews, 426 U.S. at 83; United
States v. Ferreira, 275 F.3d 1020, 1025-26 (11th Cir. 2001);
United States v. Lue, 134 F.3d 79, 87 (2d Cir. 1998); Narenji
v. Civiletti, 617 F.2d 745, 747 (D.C. Cir. 1979). Here,
Congress chose to create a distinct system of military
commissions to try non-U.S. citizens who commit war crimes.
The Government reasonably explains that “Congress had a
vital national security interest in establishing a military forum
in which to bring to justice foreign unlawful belligerents
whose purpose it is to terrorize innocent U.S. citizens and to
murder U.S. military personnel.” U.S. Panel Br. 86. Such a
wartime distinction between alien enemy combatants and U.S.
citizens easily satisfies rational basis review. Cf. Johnson v.
Eisentrager, 339 U.S. 763, 768-77 (1950). Bahlul’s equal
protection challenge has no merit.

                               V

     Bahlul also raises a First Amendment argument, claiming
that he was unconstitutionally prosecuted for his political
speech, including his production of the al Qaeda recruitment
video celebrating the terrorist attack on the U.S.S. Cole. That
argument, too, lacks any merit.

    As an initial matter, Bahlul was convicted of conspiracy
based on his conduct. The military commission found that
Bahlul, among other acts, “traveled to Afghanistan with the
                              26
purpose and intent of joining al Qaeda,” “underwent military-
type training at an al Qaeda sponsored training camp,” “acted
as personal secretary and media secretary of Usama bin Laden
in support of al Qaeda,” arranged for two September 11th
hijackers to pledge loyalty oaths to bin Laden, and “operated
and maintained data processing equipment” “for the benefit of
Usama bin Laden.” App. 122-23.

     Moreover, although non-U.S. citizens arguably may have
some First Amendment rights at Guantanamo or in other U.S.
territories for any speech they engage in there, non-U.S.
citizens have no First Amendment rights abroad in foreign
countries. The Supreme Court has applied the Constitution to
aliens in the United States and in U.S. territories, but has not
extended constitutional rights to aliens in foreign countries.
See Boumediene v. Bush, 553 U.S. 723, 768-71 (2008)
(applying Article I, Section 9 to U.S. Naval base at
Guantanamo, which was “[i]n every practical sense . . . not
abroad”); United States v. Verdugo-Urquidez, 494 U.S. 259
(1990) (declining to apply Fourth Amendment to search and
seizure of alien’s property in Mexico); Johnson v.
Eisentrager, 339 U.S. 763 (1950) (declining to apply habeas
corpus right to U.S.-controlled military prison in Germany);
see also Al Maqaleh v. Hagel, 738 F.3d 312 (D.C. Cir. 2013)
(declining to apply habeas corpus right to U.S. military base
in Afghanistan); Al Maqaleh v. Gates, 605 F.3d 84 (D.C. Cir.
2010) (same). Therefore, Bahlul had no First Amendment
rights as a non-U.S. citizen in Afghanistan when he led bin
Laden’s media operation.

     In addition, even if the First Amendment did apply to
Bahlul’s speech in Afghanistan, the Supreme Court has made
clear that the First Amendment does not protect speech such
as Bahlul’s that is “directed to inciting or producing imminent
lawless action and is likely to incite or produce such action.”
                              27
Virginia v. Black, 538 U.S. 343, 359 (2003) (quoting
Brandenburg v. Ohio, 395 U.S. 444, 447 (1969)); see also
United States v. Stevens, 559 U.S. 460, 471 (2010) (First
Amendment not understood to protect “speech or writing used
as an integral part of conduct in violation of a valid criminal
statute”). That is particularly true when the Government
seeks “to prevent imminent harms in the context of
international affairs and national security.”        Holder v.
Humanitarian Law Project, 561 U.S. 1, 35 (2010); see United
States v. Rahman, 189 F.3d 88, 116-18 (2d Cir. 1999). Under
that traditional test, the speech encompassed within the
charges against Bahlul – including a terrorist recruitment
video produced on foreign soil that “was aimed at inciting
viewers to join al Qaeda, to kill Americans, and to cause
destruction” – was not protected speech under the First
Amendment. United States v. Bahlul, 820 F. Supp. 2d 1141,
1249 (C.M.C.R. 2011) (en banc). The Constitution is not a
suicide pact. Cf. Terminiello v. City of Chicago, 337 U.S. 1,
37 (1949) (Jackson, J., dissenting).

                              VI

    A few words in response to the majority opinion: I find
the majority opinion surprising both in what it decides and in
what it declines to decide.

     First, I am surprised by what the majority opinion
decides. After all, the majority opinion reaches the same
bottom-line conclusion that this Court reached in Hamdan II:
The offense of material support for terrorism may not be tried
by military commission for conduct that occurred before the
2006 Act. But the majority opinion does so based on the Ex
Post Facto Clause alone and “overrules” Hamdan II’s
statement that the 2006 Act itself incorporates ex post facto
principles. That seems to be a meaningless exercise by the
                                28
majority opinion. Applying the canon of constitutional
avoidance, Hamdan II reasoned that the 2006 Act could not
be applied to new offenses that were not previously triable by
military commission.        Hamdan II was based on its
understanding of the limits of the Ex Post Facto Clause.
Hamdan II indicated that the 2006 Act allowed prosecutions
of the listed offenses for pre-2006 conduct to the extent that
the Ex Post Facto Clause allowed such prosecutions. As the
Court said, “Congress incorporated ex post facto principles
into the terms of” the Act. Hamdan II, 696 F.3d at 1248
(internal quotation mark omitted). So whether we apply the
Constitution to inform interpretation of the statute or we apply
the Constitution to limit the statute, the question in this case is
the same: What are the constraints imposed by the Ex Post
Facto Clause?8

     On that question, my view is that the Ex Post Facto
Clause bars retroactive prosecution at Guantanamo of new
offenses that were not previously triable by military
commission. But the majority opinion suggests (although it
does not definitively conclude) that the Ex Post Facto Clause
is less of a constraint on the Government and may allow

    8
       Judge Henderson’s concurrence, which speaks only for her,
notes quite correctly that the majority opinion today overrules
Hamdan II’s reliance on the 2006 Act (as opposed to the Ex Post
Facto Clause) as a basis for concluding that material support for
terrorism may not be tried by military commission for conduct that
occurred before the 2006 Act. What Judge Henderson does not say
in her concurrence is this indisputable fact: Based on the Ex Post
Facto Clause, the majority opinion today reaches the same result as
Hamdan II by concluding that material support for terrorism may
not be tried by military commission for conduct that occurred
before the 2006 Act, which in turn means that Salim Hamdan’s
material support for terrorism conviction was properly overturned
by this Court in Hamdan II.
                               29
military commissions at Guantanamo to retroactively
prosecute offenses that were previously triable as federal
crimes in Article III federal courts, even if those offenses were
not previously triable by military commission.

     I am surprised by this rather aggressive suggestion about
the meaning of the Ex Post Facto Clause. After all, that
position was not forcefully advocated by the Government in
its submission to the en banc Court, as the argument appeared
only in a short discussion late in its brief. In the hour-long
oral argument, moreover, the Government did not advance
that argument, and no Judge asked any question along those
lines or suggested this as a possible approach.

     Moreover, like Judge Brown (as well as Judge Rogers), I
too respectfully have serious doubts about the majority
opinion’s suggestion that the Ex Post Facto Clause may allow
military commissions to retroactively prosecute crimes that
were previously triable as federal crimes in federal court even
when they were not previously triable by military
commission. Can Congress, consistent with the Ex Post Facto
Clause, really just pull out the federal criminal code and make
offenses retroactively triable before military commissions? I
am aware of no commentator who has taken that position or
even analyzed the question. I have found no precedent taking
that position or analyzing the question. And even Congress,
hardly in a passive mode when it enacted the 2006 Act, did
not go so far as the majority opinion about the meaning of the
Ex Post Facto Clause. The text of the 2006 Act reveals that
Congress thought there was no ex post facto problem because
the listed offenses were previously triable by military
commission. See 10 U.S.C. § 950p(a) (2006). If Congress
had thought it enough that there were some prior federal
criminal statutes on the books, Congress no doubt would have
relied on that point to respond to the ex post facto concerns.
                               30
But as best as I can tell, no Member said as much. On the
contrary, the text of the Act itself demonstrates that Congress
thought it necessary, in order to overcome ex post facto
objections, to show that the offenses had been previously
triable by military commission.

     It is especially surprising for the majority opinion to take
its doubly aggressive approach – overruling one aspect of a
precedent of this Court and advancing a heretofore unheard-of
view of the Ex Post Facto Clause’s application to military
commissions – when it is unnecessary to do so here. After all,
in what it terms an “independent and alternative” holding, the
majority opinion says that plain error review applies and
concludes that the conspiracy conviction was not plain error
because conspiracy at least arguably was triable by military
commission under Section 821 at the time of Bahlul’s
conduct. The majority opinion notes, correctly, that it is
impossible to describe the Government’s position on
conspiracy and Section 821 as plain error when the issue
remains open in the Supreme Court and three Justices in
Hamdan agreed with the Government’s position. The
majority opinion could have said no more than what it says
about Section 821 to resolve the conspiracy ex post facto
issue for purposes of Bahlul’s appeal.

    Second, from the other direction, I am also surprised by
what the majority opinion does not decide. We took this case
en banc specifically to decide whether, consistent with the Ex
Post Facto Clause, a military commission could try
conspiracy for conduct that occurred before the 2006 Act.
Yet the majority opinion does not actually decide that
question.

     That is because the majority opinion applies the plain
error standard of review. The majority opinion thus does not
                               31
decide whether there was error in the conspiracy conviction;
instead, it decides only whether any alleged error was plain.

     Like Judge Brown (as well as Judge Rogers), I too
disagree with the majority opinion’s use of a plain error
standard of review. To begin with, Bahlul did not forfeit his
ex post facto objection, so he is legally entitled to de novo
review of that issue and does not have to meet the high bar of
showing plain error. Bahlul raised an ex post facto issue
when he pled not guilty and, among other things, posed to the
Military Judge a “legal question”: “Does the law here start
from before, during, or after?” Supp. App. 37; see id. (Bahlul
asking whether “the law here” “stems from the action, before
action, or post action?”).

     But put that aside. Even if Bahlul did not expressly raise
an ex post facto objection at trial, the issue is not forfeitable
under Rules 905 and 907 of the Rules of Military
Commissions. Those Rules contain two exceptions to the
usual forfeiture rules for objections based on a “lack of
jurisdiction” or “failure of a charge to allege an offense.”
MANUAL FOR MILITARY COMMISSIONS pt. II, at II-83-84
(2007); see id. at II-87; see also MANUAL FOR MILITARY
COMMISSIONS pt. II, at II-89-91, II-95 (2012). In this case,
each of those two exceptions applies. As the relevant statutes
say on their face, the question of whether conspiracy may be
charged is jurisdictional – whether the military commission
had “jurisdiction” over the offense. 10 U.S.C. § 948d(a)
(2006) (military commissions have “jurisdiction to try any
offense made punishable by this chapter or the law of war”)
(emphasis added); 10 U.S.C. § 821 (2000) (“provisions of this
chapter conferring jurisdiction upon courts-martial do not
deprive military commissions . . . of concurrent jurisdiction
with respect to offenders or offenses that by statute or by the
law of war may be tried by military commissions”) (emphases
                                 32
added). Indeed, the Military Judge construed Bahlul’s
sometimes rambling comments as an objection to the military
commission’s jurisdiction. See Supp. App. at 31-32.

     And in any event, the question raised by Bahlul in this
Court is surely whether the conspiracy charge fails to “allege
an offense,” which is the other kind of non-forfeitable
objection under Rules 905 and 907.9 Although there is
obviously scarce precedent interpreting the recently
promulgated Rules of Military Commissions with respect to a
charge that fails to state an offense, the same basic language is
found in Federal Rule of Criminal Procedure 12(b)(3)(B).
That Criminal Rule provides an exception to waiver or
forfeiture in criminal cases for, among other things, a claim
that the indictment or information “fails to state an offense.”
Interpreting that language, courts have determined that
constitutional objections such as Ex Post Facto Clause claims
challenging the validity of the charge are objections that the
charge failed to state an offense – and thus may be raised for
the first time on appeal and reviewed de novo even if those
objections were not timely raised in the district court
proceedings. See United States v. Haddock, 956 F.2d 1534,
1542 (10th Cir. 1992) (reviewing de novo Ex Post Facto
Clause challenge that was not raised prior to trial); United
States v. Gilbert, 813 F.2d 1523, 1528-29 (9th Cir. 1987)
(constitutional challenges attacking “the sufficiency of the
information to charge an offense . . . may be raised for the

     9
       Rules 905 and 907 are entitled “waiver” but those Rules, like
the other Rules of Military Commissions, use that term
(imprecisely) to cover both waived arguments and forfeited
arguments. See MANUAL FOR MILITARY COMMISSIONS pt. II, at II-
83-84, II-87 (2007); MANUAL FOR MILITARY COMMISSIONS pt. II,
at II-89-91, II-95 (2012); see also Rules 920(f), 1005(f), 1106(e)(6),
MANUAL FOR MILITARY COMMISSIONS pt. II, at II-115, II-125, II-
145 (2007).
                                 33
first time on appeal”); United States v. Seuss, 474 F.2d 385,
387 n.2 (1st Cir. 1973) (“The defense of failure of an
indictment to charge an offense includes the claim that the
statute apparently creating the offense is unconstitutional.
That objection may be raised for the first time on appeal.”);
see also United States v. Al Hedaithy, 392 F.3d 580, 586 (3d
Cir. 2004) (reviewing de novo Rule 12(b)(3)(B) objection that
was not raised at trial); United States v. Panarella, 277 F.3d
678, 682-86 (3d Cir. 2002) (same); United States v. Maybee,
No. 11-30006, 2011 WL 2784446, at *3 (W.D. Ark. July 15,
2011) (“Courts have held that a claim that the indictment fails
to ‘charge an offense’ includes a claim that the statute
creating the offense is unconstitutional.”), aff’d, 687 F.3d
1026 (8th Cir. 2012); United States v. Thomas, 534 F. Supp.
2d 912, 915 (N.D. Iowa 2008) (“It is settled that a claim that
the indictment fails to state an offense under Rule 12(b)(3)(B)
includes a claim that the statute creating the offense is
unconstitutional.”) (internal quotation marks and ellipses
omitted), aff’d sub nom. United States v. Howell, 552 F.3d
709 (8th Cir. 2009); MOORE’S FEDERAL PRACTICE § 612.04
(Lexis 2014) (“The defense of failure to charge an offense
may be based on the absence of an essential element in the
indictment, indefiniteness of allegations, the lack of a statute
creating the crime, or the unconstitutionality of the statute
relied upon.”).10

     10
        Notably, the Advisory Committee on the Federal Rules of
Criminal Procedure has recently recommended changing this aspect
of Rule 12(b)(3)(B), apparently because it is somewhat too lenient.
Under the proposed change, the argument that a charge failed to
state an offense would no longer be an exception to the usual rules
governing waiver and forfeiture. In other words, a defendant would
no longer be able to raise an argument that the charge failed to state
an offense for the first time on appeal and still receive de novo
review of that claim. See SUMMARY OF THE REPORT OF THE
JUDICIAL CONFERENCE COMMITTEE ON RULES OF PRACTICE AND
                                 34

     Finally, even if the issue had been forfeited and plain
error review applied, the majority opinion still would possess
discretion to decide the ex post facto issue under the first
prong of the plain error test as defined by the Supreme Court
and conclude that there was no “error” in the conspiracy
conviction. See United States v. Olano, 507 U.S. 725, 732
(1993). The majority opinion should do so. Courts have an
appropriate role in times of war to decide certain justiciable
disputes – but we should do so “with as much clarity and
expedition as possible.” Kiyemba v. Obama, 561 F.3d 509,
522 (D.C. Cir. 2009) (Kavanaugh, J., concurring). The
majority opinion’s failure to decide the ex post facto question
with respect to conspiracy does not comport with that
principle, in my respectful view. Given the various pending
cases raising the same question and the need for guidance in
those wartime tribunals, I believe that the majority opinion
should decide the issue.

      On top of not deciding how the ex post facto principle
applies to conspiracy trials before military commissions, the
majority opinion also does not decide Bahlul’s Article I, jury
trial, equal protection, or First Amendment challenges, but
rather sends those four issues back to a three-judge panel for
resolution. I also respectfully disagree with that approach.
The remaining issues are not that complicated; we have the

PROCEDURE, Rules Appendix C-15-C-26 (Sept. 2013). But that
proposed rule change, which has not yet taken effect, just highlights
what the “fails to state an offense” language means now in the
Criminal Rules. And that is the same language that the Rules of
Military Commissions uses. Unless and until the Rules of Military
Commissions are likewise changed, therefore, an argument that a
military commission charge failed to state an offense – such as the
Ex Post Facto Clause argument here – may be raised for the first
time on appeal and receive de novo review.
                               35
requisite briefing; and we could request supplemental briefing
if need be. Moreover, those issues are especially easy to
decide on plain error review, which after all is the standard of
review that the majority opinion indicates must be applied to
those issues. Sending the case back to a three-judge panel
will delay final resolution of this case, likely until some point
in 2015, given the time it will take for a decision by the three-
judge panel and then resolution of any future petitions for
panel rehearing or rehearing en banc. Like Judge Brown, I
believe that we should resolve the case now, not send it back
to the three-judge panel.

     In short, I respectfully disagree with the majority
opinion’s addressing the ex post facto issue in a way that does
not actually decide the legal issue with respect to conspiracy
and provides little clarity or guidance on that issue going
forward, and also with its sending the other four issues back
to a three-judge panel. There is a time to avoid and a time to
decide. Now is the time to decide.

                              ***

    In sum, I would affirm Bahlul’s conspiracy conviction,
vacate the material support for terrorism and solicitation
convictions as ex post facto violations, and remand to the U.S.
Court of Military Commission Review for it to address the
consequences, if any, for Bahlul’s life sentence.11

    11
        The Supreme Court in Quirin affirmed the Nazi saboteurs’
convictions and sentences on one charge and declined to review
their convictions on the remaining charges. See Ex parte Quirin,
317 U.S. 1, 46 (1942). That approach reflected the practice at the
time for American appellate review of criminal convictions. The
modern American appellate practice, however, is to address each
conviction separately in these circumstances. See Rutledge v.
United States, 517 U.S. 292, 301-03 (1996); Ray v. United States,
                                36




481 U.S. 736, 736-37 (1987). Absent contrary indication, I assume
that Congress intended appellate review under the Military
Commissions Acts of 2006 and 2009 to proceed in the same
manner as modern appellate review of multiple criminal
convictions. For that reason and because a sentence was not
specified for each individual offense in this case, I have addressed
the material support for terrorism and solicitation offenses as well
as the conspiracy offense.
