(Slip Opinion)              OCTOBER TERM, 2019                                       1

                                       Syllabus

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


SUPREME COURT OF THE UNITED STATES

                                       Syllabus

   OPATI, IN HER OWN RIGHT AND AS EXECUTRIX OF THE
  ESTATE OF OPATI, DECEASED, ET AL. v. REPUBLIC
                  OF SUDAN ET AL.

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

    No. 17–1268. Argued February 24, 2020—Decided May 18, 2020
In 1998, al Qaeda operatives detonated truck bombs outside the United
  States Embassies in Kenya and Tanzania. Victims and their family
  members sued the Republic of Sudan under the state-sponsored ter-
  rorism exception to the Foreign Sovereign Immunities Act (FSIA), for-
  merly 28 U. S. C. §1605(a)(7), alleging that Sudan had assisted al
  Qaeda in perpetrating the attacks. At the time, the plaintiffs faced
  §1606’s bar on punitive damages for suits proceeding under any of the
  §1605 sovereign immunity exceptions. In 2008, Congress amended the
  FSIA in the National Defense Authorization Act (NDAA). 122 Stat. 3.
  In NDAA §1083(a), Congress moved §1605(a)(7) to a new section and
  created an express federal cause of action for acts of terror that also
  provided for punitive damages. See §1605A(c). In §1083(c)(2), it gave
  effect to existing lawsuits that had been “adversely affected” by prior
  law “as if” they had been originally filed under the new §1605A(c). And
  in §1083(c)(3), it provided a time-limited opportunity for plaintiffs to
  file new actions “arising out of the same act or incident” as an earlier
  action and claim §1605A’s benefits. Following these amendments, the
  original plaintiffs amended their complaint to include the new federal
  cause of action under §1605A(c), and hundreds of others filed new, sim-
  ilar claims. The district court entered judgment for the plaintiffs and
  awarded approximately $10.2 billion in damages, including roughly
  $4.3 billion in punitive damages. As relevant here, the court of appeals
  held that the plaintiffs were not entitled to punitive damages because
  Congress had included no statement in NDAA §1083 clearly authoriz-
  ing punitive damages for preenactment conduct.
2                  OPATI v. REPUBLIC OF SUDAN

                                 Syllabus

Held: Plaintiffs in a federal cause of action under §1605A(c) may seek
 punitive damages for preenactment conduct. Even assuming (without
 granting) that Sudan may claim the benefit of the presumption of pro-
 spectivity—the assumption that Congress means its legislation to
 apply only to future conduct, see Landgraf v. USI Film Products, 511
 U. S. 244—Congress was as clear as it could have been when it ex-
 pressly authorized punitive damages under §1605A(c) and explicitly
 made that new cause of action available to remedy certain past acts of
 terrorism.
    Sudan stresses that §1083(c) does not itself contain an express au-
 thorization of punitive damages. It does admit that §1083(c) author-
 izes plaintiffs to bring §1605A(c) claims for preenactment conduct.
 And it does concede that §1605A(c) allows for damages that “may in-
 clude economic damages, solatium, [and] pain and suffering” for preen-
 actment conduct. That list in the statute also “include[s] . . . punitive
 damages,” and no plausible account of §1083(c) could be clear enough
 to authorize the retroactive application of all other §1605A(c) features
 except punitive damages. Sudan also contends that §1605A(c)’s word-
 ing “may include . . . punitive damages” fails the clarity test. But “ ‘the
 word “may” clearly connotes discretion,’ ” Halo Electronics, Inc. v.
 Pulse Electronics, Inc., 579 U. S. ___, ___, and simply vests district
 courts with discretion to determine whether punitive damages are ap-
 propriate. In addition, all of the categories of special damages men-
 tioned in §1605A(c) are provided on equal terms. Finally, Sudan sug-
 gests that a super-clarity rule should apply here because retroactive
 punitive damages raise special constitutional concerns. Such an inter-
 pretative rule is not reasonably administrable.
    This Court declines to resolve other matters raised by the parties
 outside the question presented. But having decided that punitive dam-
 ages are permissible for federal claims and that the reasons the court
 of appeals offered for its contrary decision were mistaken, it follows
 that the court of appeals must also reconsider its decision concerning
 the availability of punitive damages for claims proceeding under state
 law. Pp. 6–12.
864 F. 3d 751, vacated and remanded.

  GORSUCH, J., delivered the opinion of the Court, in which all other
Members joined, except KAVANAUGH, J., who took no part in the consid-
eration or decision of the case.
                        Cite as: 590 U. S. ____ (2020)                                 1

                              Opinion of the Court

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


SUPREME COURT OF THE UNITED STATES
                                    _________________

                                    No. 17–1268
                                    _________________


 MONICAH OKOBA OPATI, IN HER OWN RIGHT, AND
 AS EXECUTRIX OF THE ESTATE OF CAROLINE SETLA
     OPATI, DECEASED, ET AL., PETITIONERS v.
           REPUBLIC OF SUDAN, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
    APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT
                                  [May 18, 2020]

   JUSTICE GORSUCH delivered the opinion of the Court.
   In 1998, al Qaeda operatives simultaneously detonated
truck bombs outside the United States Embassies in Kenya
and Tanzania. Hundreds died, thousands were injured. In
time, victims and their family members sued the Republic
of Sudan in federal court, alleging that it had assisted al
Qaeda in perpetrating the attacks. After more than a dec-
ade of motions practice, intervening legislative amend-
ments, and a trial, the plaintiffs proved Sudan’s role in the
attacks and established their entitlement to compensatory
and punitive damages. On appeal, however, Sudan argued,
and the court agreed, that the Foreign Sovereign Immuni-
ties Act barred the punitive damages award. It is that de-
cision we now review and, ultimately, vacate.
                             *
  The starting point for nearly any dispute touching on for-
eign sovereign immunity lies in Schooner Exchange v.
McFaddon, 7 Cranch 116 (1812). There, Chief Justice Mar-
2               OPATI v. REPUBLIC OF SUDAN

                      Opinion of the Court

shall explained that foreign sovereigns do not enjoy an in-
herent right to be held immune from suit in American
courts: “The jurisdiction of the nation within its own terri-
tory is necessarily exclusive and absolute. It is susceptible
of no limitation not imposed by itself.” Id., at 136. Still,
Chief Justice Marshall continued, many countries had de-
clined to exercise jurisdiction over foreign sovereigns in
cases involving foreign ministers and militaries. Id., at
137–140. And, accepting a suggestion from the Executive
Branch, the Court agreed as a matter of comity to extend
that same immunity to a foreign sovereign in the case at
hand. Id., at 134, 145–147.
   For much of our history, claims of foreign sovereign im-
munity were handled on a piecework basis that roughly
paralleled the process in Schooner Exchange. Typically, af-
ter a plaintiff sought to sue a foreign sovereign in an Amer-
ican court, the Executive Branch, acting through the State
Department, filed a “suggestion of immunity”—case-spe-
cific guidance about the foreign sovereign’s entitlement to
immunity. See Verlinden B. V. v. Central Bank of Nigeria,
461 U. S. 480, 487 (1983). Because foreign sovereign im-
munity is a matter of “grace and comity,” Republic of Aus-
tria v. Altmann, 541 U. S. 677, 689 (2004), and so often im-
plicates judgments the Constitution reserves to the political
branches, courts “consistently . . . deferred” to these sugges-
tions. Verlinden, 461 U. S., at 486.
   Eventually, though, this arrangement began to break
down. In the mid-20th century, the State Department
started to take a more restrictive and nuanced approach to
foreign sovereign immunity. See id., at 486–487. Some-
times, too, foreign sovereigns neglected to ask the State De-
partment to weigh in, leaving courts to make immunity de-
cisions on their own.         See id., at 487–488.         “Not
surprisingly” given these developments, “the governing
standards” for foreign sovereign immunity determinations
over time became “neither clear nor uniformly applied.” Id.,
                 Cite as: 590 U. S. ____ (2020)            3

                     Opinion of the Court

at 488.
   In 1976, Congress sought to remedy the problem and ad-
dress foreign sovereign immunity on a more comprehensive
basis. The result was the Foreign Sovereign Immunities
Act (FSIA). As a baseline rule, the FSIA holds foreign
states and their instrumentalities immune from the juris-
diction of federal and state courts. See 28 U. S. C.
§§1603(a), 1604. But the law also includes a number of ex-
ceptions. See, e.g., §§1605, 1607. Of particular relevance
today is the terrorism exception Congress added to the law
in 1996. That exception permits certain plaintiffs to bring
suits against countries who have committed or supported
specified acts of terrorism and who are designated by the
State Department as state sponsors of terror. Still, as orig-
inally enacted, the exception shielded even these countries
from the possibility of punitive damages. See Antiterrorism
and Effective Death Penalty Act of 1996 (codifying state-
sponsored terrorism exception at 28 U. S. C. §1605(a)(7));
§1606 (generally barring punitive damages in suits pro-
ceeding under any of §1605’s sovereign immunity excep-
tions).
   Two years after Congress amended the FSIA, al Qaeda
attacked the U. S. Embassies in Kenya and Tanzania. In
response, a group of victims and affected family members
led by James Owens sued Sudan in federal district court,
invoking the newly adopted terrorism exception and alleg-
ing that Sudan had provided shelter and other material
support to al Qaeda. As the suit progressed, however, a
question emerged. In its recent amendments, had Congress
merely withdrawn immunity for state-sponsored terrorism,
allowing plaintiffs to proceed using whatever pre-existing
causes of action might be available to them? Or had Con-
gress gone further and created a new federal cause of action
to address terrorism? Eventually, the D. C. Circuit held
that Congress had only withdrawn immunity without cre-
ating a new cause of action. See Cicippio-Puelo v. Islamic
4               OPATI v. REPUBLIC OF SUDAN

                      Opinion of the Court

Republic of Iran, 353 F. 3d 1024, 1033 (2004).
   In response to that and similar decisions, Congress
amended the FSIA again in the National Defense Authori-
zation Act for Fiscal Year 2008 (NDAA), 122 Stat. 338. Four
changes, all found in a single section, bear mention here.
First, in §1083(a) of the NDAA, Congress moved the state-
sponsored terrorism exception from its original home in
§1605(a)(7) to a new section of the U. S. Code, 28 U. S. C.
§1605A. This had the effect of freeing claims brought under
the terrorism exception from the FSIA’s usual bar on puni-
tive damages. See §1606 (denying punitive damages in
suits proceeding under a sovereign immunity exception
found in §1605 but not §1605A). Second, also in §1083(a),
Congress created an express federal cause of action for acts
of terror. This new cause of action, codified at 28 U. S. C.
§1605A(c), is open to plaintiffs who are U. S. nationals,
members of the Armed Forces, U. S. government employees
or contractors, and their legal representatives, and it ex-
pressly authorizes punitive damages. Third, in §1083(c)(2)
of the NDAA, a provision titled “Prior Actions,” Congress
addressed existing lawsuits that had been “adversely af-
fected on the groun[d] that” prior law “fail[ed] to create a
cause of action against the state.” Actions like these, Con-
gress instructed, were to be given effect “as if ” they had
been originally filed under §1605A(c)’s new federal cause of
action. Finally, in §1083(c)(3) of the NDAA, a provision ti-
tled “Related Actions,” Congress provided a time-limited
opportunity for plaintiffs to file new actions “arising out of
the same act or incident” as an earlier action and claim the
benefits of 28 U. S. C. §1605A.
   Following these amendments, the Owens plaintiffs
amended their complaint to include the new federal cause
of action, and hundreds of additional victims and family
members filed new claims against Sudan similar to those in
Owens. Some of these new plaintiffs were U. S. nationals
or federal government employees or contractors who sought
                  Cite as: 590 U. S. ____ (2020)            5

                      Opinion of the Court

relief under the new §1605A(c) federal cause of action. But
others were the foreign-national family members of U. S.
government employees or contractors killed or injured in
the attacks. Ineligible to invoke §1605A(c)’s new federal
cause of action, these plaintiffs relied on §1605A(a)’s state-
sponsored terrorism exception to overcome Sudan’s sover-
eign immunity and then advance claims sounding in state
law.
   After a consolidated bench trial in which Sudan declined
to participate, the district court entered judgment in favor
of the plaintiffs. District Judge John Bates offered detailed
factual findings explaining that Sudan had knowingly
served as a safe haven near the two United States Embas-
sies and allowed al Qaeda to plan and train for the attacks.
The court also found that Sudan had provided hundreds of
Sudanese passports to al Qaeda, allowed al Qaeda opera-
tives to travel over the Sudan-Kenya border without re-
striction, and permitted the passage of weapons and money
to supply al Qaeda’s cell in Kenya. See Owens v. Republic
of Sudan, 826 F. Supp. 2d 128, 139–146 (DC 2011).
   The question then turned to damages. Given the exten-
sive and varied nature of the plaintiffs’ injuries, the court
appointed seven Special Masters to aid its factfinding.
Over more than two years, the Special Masters conducted
individual damages assessments and submitted written re-
ports. Based on these reports, and after adding a substan-
tial amount of prejudgment interest to account for the many
years of delay, the district court awarded a total of approx-
imately $10.2 billion in damages, including roughly $4.3
billion in punitive damages to plaintiffs who had brought
suit in the wake of the 2008 amendments.
   At that point, Sudan decided to appear and appeal.
Among other things, Sudan sought to undo the district
court’s punitive damages award. Generally, Sudan argued,
Congress may create new forms of liability for past conduct
only by clearly stating its intention to do so. And, Sudan
6               OPATI v. REPUBLIC OF SUDAN

                     Opinion of the Court

continued, when Congress passed the NDAA in 2008, it no-
where clearly authorized punitive damages for anything
countries like Sudan might have done in the 1990s.
   The court of appeals agreed. It started by addressing the
plaintiffs who had proceeded under the new federal cause
of action in §1605A(c). The court noted that, in passing the
NDAA, Congress clearly authorized individuals to use the
Prior Actions and Related Actions provisions to bring new
federal claims attacking past conduct. Likewise, the law
clearly allowed these plaintiffs to collect compensatory
damages for their claims. But, the court held, Congress in-
cluded no statement clearly authorizing punitive damages
for preenactment conduct. See Owens v. Republic of Sudan,
864 F. 3d 751, 814–817 (CADC 2017). Separately but for
essentially the same reasons, the court held that the for-
eign-national family member plaintiffs who had proceeded
under state-law causes of action were also barred from
seeking and obtaining punitive damages. Id., at 817.
   The petitioners responded by asking this Court to review
the first of these rulings and decide whether the 2008
NDAA amendments permit plaintiffs proceeding under the
federal cause of action in §1605A(c) to seek and win puni-
tive damages for past conduct. We agreed to resolve that
question. 588 U. S. ___ (2019).
                               *
  The principle that legislation usually applies only pro-
spectively “is deeply rooted in our jurisprudence, and em-
bodies a legal doctrine centuries older than our Republic.”
Landgraf v. USI Film Products, 511 U. S. 244, 265 (1994).
This principle protects vital due process interests, ensuring
that “individuals . . . have an opportunity to know what the
law is” before they act, and may rest assured after they act
that their lawful conduct cannot be second-guessed later.
Ibid. The principle serves vital equal protection interests
as well: If legislative majorities could too easily make new
                  Cite as: 590 U. S. ____ (2020)             7

                      Opinion of the Court

laws with retroactive application, disfavored groups could
become easy targets for discrimination, with their past ac-
tions visible and unalterable. See id., at 266–267. No
doubt, reasons like these are exactly why the Constitution
discourages retroactive lawmaking in so many ways, from
its provisions prohibiting ex post facto laws, bills of attain-
der, and laws impairing the obligations of contracts, to its
demand that any taking of property be accompanied by just
compensation. See id., at 266.
   Still, Sudan doesn’t challenge the constitutionality of the
2008 NDAA amendments on these or any other grounds—
the arguments we confront today are limited to the field of
statutory interpretation. But, as both sides acknowledge,
the principle of legislative prospectivity plays an important
role here too. In fact, the parties devote much of their brief-
ing to debating exactly how that principle should inform our
interpretation of the NDAA.
   For its part, Sudan points to Landgraf. There, the Court
observed that, “in decisions spanning two centuries,” we
have approached debates about statutory meaning with an
assumption that Congress means its legislation to respect
the principle of prospectivity and apply only to future con-
duct—and that, if and when Congress wishes to test its
power to legislate retrospectively, it must say so “clear[ly].”
Id., at 272. All this is important, Sudan tells us, because
when we look to the NDAA we will find no clear statement
allowing courts to award punitive damages for past con-
duct.
   But if Sudan focuses on the rule, the petitioners highlight
an exception suggested by Altmann. Because foreign sov-
ereign immunity is a gesture of grace and comity, Altmann
reasoned, it is also something that may be withdrawn ret-
roactively without the same risk to due process and equal
protection principles that other forms of backward-looking
legislation can pose. Foreign sovereign immunity’s “princi-
pal purpose,” after all, “has never been to permit foreign
8               OPATI v. REPUBLIC OF SUDAN

                      Opinion of the Court

states . . . to shape their conduct in reliance on the promise
of future immunity from suit in United States courts.” 541
U. S., at 696. Thus, Altmann held, “[i]n th[e] sui generis
context [of foreign sovereign immunity], . . . it [is] more ap-
propriate, absent contraindications, to defer to the most re-
cent decision [of the political branches] than to presume
that decision inapplicable merely because it postdates the
conduct in question.” Ibid. And, the petitioners stress, once
the presumption of prospectivity is swept away, the NDAA
is easily read to authorize punitive damages for completed
conduct.
   Really, this summary only begins to scratch the surface
of the parties’ debate. Sudan replies that it may be one
thing to retract immunity retroactively consistent with Alt-
mann, because all that does is open a forum to hear an oth-
erwise available legal claim. But it is another thing entirely
to create new rules regulating primary conduct and impose
them retroactively. When Congress wishes to do that, Su-
dan says, it must speak just as clearly as Landgraf com-
manded. And, Sudan adds, the NDAA didn’t simply open a
new forum to hear a pre-existing claim; it also created a new
cause of action governing completed conduct that the peti-
tioners now seek to exploit. Cf. Altmann, 541 U. S., at 702–
704 (Scalia, J., concurring). In turn, the petitioners retort
that Altmann itself might have concerned whether a new
forum could hear an otherwise available and pre-existing
claim, but its reasoning went further. According to the pe-
titioners, the decision also strongly suggested that the pre-
sumption of prospectivity does not apply at all when it
comes to suits against foreign sovereigns, full stop. These
points and more the parties develop through much of their
briefing before us.
   As we see it, however, there is no need to resolve the par-
ties’ debate over interpretive presumptions. Even if we as-
sume (without granting) that Sudan may claim the benefit
of Landgraf ’s presumption of prospectivity, Congress was
                 Cite as: 590 U. S. ____ (2020)            9

                     Opinion of the Court

as clear as it could have been when it authorized plaintiffs
to seek and win punitive damages for past conduct using
§1065A(c)’s new federal cause of action. After all, in
§1083(a), Congress created a federal cause of action that ex-
pressly allows suits for damages that “may include eco-
nomic damages, solatium, pain and suffering, and punitive
damages.” (Emphasis added.) This new cause of action was
housed in a new provision of the U. S. Code, 28 U. S. C.
§1605A, to which the FSIA’s usual prohibition on punitive
damages does not apply. See §1606. Then, in §§1083(c)(2)
and (c)(3) of the very same statute, Congress allowed cer-
tain plaintiffs in “Prior Actions” and “Related Actions” to
invoke the new federal cause of action in §1605A. Both pro-
visions specifically authorized new claims for preenactment
conduct. Put another way, Congress proceeded in two
equally evident steps: (1) It expressly authorized punitive
damages under a new cause of action; and (2) it explicitly
made that new cause of action available to remedy certain
past acts of terrorism. Neither step presents any ambigu-
ity, nor is the NDAA fairly susceptible to any competing in-
terpretation.
   Sudan’s primary rejoinder only serves to underscore the
conclusion. Like the court of appeals before it, Sudan
stresses that §1083(c) itself contains no express authoriza-
tion of punitive damages. But it’s hard to see what differ-
ence that makes. Sudan admits that §1083(c) authorizes
plaintiffs to bring claims under §1605A(c) for acts commit-
ted before the 2008 amendments. Sudan concedes, too, that
§1605A(c) authorizes plaintiffs to seek and win “economic
damages, solatium, [and] pain and suffering,” for preenact-
ment conduct. In fact, except for the two words “punitive
damages,” Sudan accepts that every other jot and tittle of
§1605A(c) applies to actions properly brought under
§1083(c) for past conduct. And we can see no plausible ac-
count on which §1083(c) could be clear enough to authorize
the retroactive application of all other features of
10              OPATI v. REPUBLIC OF SUDAN

                      Opinion of the Court

§1605A(c), just not these two words.
   Sudan next contends that §1605A(c) fails to authorize ret-
roactive punitive damages with sufficient clarity because it
sounds equivocal—the provision says only that awards
“may” include punitive damages. But this language simply
vests district courts with discretion to determine whether
punitive damages are appropriate in view of the facts of a
particular case. As we have repeatedly observed when dis-
cussing remedial provisions using similar language, “the
‘word “may” clearly connotes discretion.’ ” Halo Electronics,
Inc. v. Pulse Electronics, Inc., 579 U. S. ___, ___ (2016) (slip
op., at 8) (quoting Martin v. Franklin Capital Corp., 546
U. S. 132, 136 (2005), in turn quoting Fogerty v. Fantasy,
Inc., 510 U. S. 517, 533 (1994); emphasis added). What’s
more, all of the categories of special damages mentioned in
§1605A(c) are provided on equal terms: “[D]amages may
include economic damages, solatium, pain and suffering,
and punitive damages.” (Emphasis added.) Sudan admits
that the statute vests the district court with discretion to
award the first three kinds of damages for preenactment
conduct—and the same can be no less true when it comes to
the fourth.
   That takes us to Sudan’s final argument. Maybe Con-
gress did act clearly when it authorized a new cause of ac-
tion and other forms of damages for past conduct. But be-
cause retroactive damages of the punitive variety raise
special constitutional concerns, Sudan says, we should cre-
ate and apply a new rule requiring Congress to provide a
super-clear statement when it wishes to authorize their
use.
   We decline this invitation. It’s true that punitive dam-
ages aren’t merely a form a compensation but a form of pun-
ishment, and we don’t doubt that applying new punish-
ments to completed conduct can raise serious constitutional
questions. See Landgraf, 511 U. S., at 281. But if Congress
                  Cite as: 590 U. S. ____ (2020)           11

                      Opinion of the Court

clearly authorizes retroactive punitive damages in a man-
ner a litigant thinks unconstitutional, the better course is
for the litigant to challenge the law’s constitutionality, not
ask a court to ignore the law’s manifest direction. Besides,
when we fashion interpretive rules, we usually try to en-
sure that they are reasonably administrable, comport with
linguistic usage and expectations, and supply a stable back-
drop against which Congress, lower courts, and litigants
may plan and act. See id., at 272–273. And Sudan’s pro-
posal promises more nearly the opposite: How much
clearer-than-clear should we require Congress to be when
authorizing the retroactive use of punitive damages? Su-
dan doesn’t even try to say, except to assure us it knows a
super-clear statement when it sees it, and can’t seem to find
one here. That sounds much less like an administrable rule
of law than an appeal to the eye of the beholder.
                               *
   With the question presented now resolved, both sides ask
us to tackle other matters in this long-running litigation.
Perhaps most significantly, the petitioners include a post-
script asking us to decide whether Congress also clearly au-
thorized retroactive punitive damages in claims brought by
foreign-national family members under state law using
§1605A(a)’s exception to sovereign immunity. Sudan in-
sists that, if we take up that question, we must account for
the fact that §1605A(a), unlike §1605A(c), does not ex-
pressly discuss punitive damages. And in fairness, Sudan
contends, we should also resolve whether litigants may in-
voke state law at all, in light of the possibility that
§1605A(c) now supplies the exclusive cause of action for
claims involving state-sponsored acts of terror.
   We decline to resolve these or other matters outside the
question presented. The petitioners chose to limit their pe-
tition to the propriety of punitive damages under the fed-
eral cause of action in §1605A(c). See Pet. for Cert. i. The
12              OPATI v. REPUBLIC OF SUDAN

                     Opinion of the Court

Solicitor General observed this limitation in the question
presented at the petition stage. See Brief for United States
as Amicus Curiae 19, n. 8. The parties’ briefing and argu-
ment on matters outside the question presented has been
limited, too, and we think it best not to stray into new ter-
rain on the basis of such a meager invitation and with such
little assistance.
   Still, we acknowledge one implication that necessarily
follows from our holding today. The court of appeals re-
fused to allow punitive damages awards for foreign-na-
tional family members proceeding under state law for “the
same reason” it refused punitive damages for the plaintiffs
proceeding under §1605A(c)’s federal cause of action. 864
F. 3d, at 818. The court stressed that it would be “puzzling”
if punitive damages were permissible for state claims but
not federal ones. Id., at 817. Having now decided that pu-
nitive damages are permissible for federal claims, and that
the reasons the court of appeals offered for its contrary de-
cision were mistaken, it follows that the court of appeals
must also reconsider its decision concerning the availability
of punitive damages for claims proceeding under state law.
   The judgment of the court of appeals with respect to pu-
nitive damages is vacated. The case is remanded for further
proceedings consistent with this opinion.

                                             It is so ordered.

  JUSTICE KAVANAUGH took no part in the consideration or
decision of this case.
