No. 16-1307

In the Supreme Court of the United States
ALI HAMZA AHMAD SULIMAN AL BAHLUL, PETITIONER
v.
UNITED STATES OF AMERICA
ON PETITION FOR A WRIT OF CERTIORARI
TO THE UNITED STATES COURT OF APPEALS
FOR THE DISTRICT OF COLUMBIA CIRCUIT

BRIEF FOR THE UNITED STATES IN OPPOSITION

JEFFREY B. WALL
Acting Solicitor General
Counsel of Record
DANA J. BOENTE
Acting Assistant Attorney
General
JOSEPH F. PALMER
DANIELLE S. TARIN
Attorneys
Department of Justice
Washington, D.C. 20530-0001
SupremeCtBriefs@usdoj.gov
(202) 514-2217

 QUESTIONS PRESENTED

1. Whether the military commission plainly erred in
not sua sponte dismissing the charge against petitioner
of conspiracy to commit war crimes on the ground that
Congress violated Article III by making that offense
triable by military commission.
2. Whether the Military Commissions Act of 2006
(2006 MCA), 10 U.S.C. 948a et seq. (2006), authorizes
prosecutions for conspiracy to commit war crimes based
on conduct committed before its enactment.
3. Whether petitioner’s conspiracy conviction based
on conduct that pre-dated enactment of the 2006 MCA
plainly violated the Ex Post Facto Clause.
4. Whether the 2006 MCA plainly violated the equal
protection component of the Due Process Clause because
it limited the jurisdiction of military commissions to offenses committed by alien unlawful enemy combatants.

(I)

 TABLE OF CONTENTS

Page
Opinions below .............................................................................. 1
Jurisdiction .................................................................................... 1
Statement ...................................................................................... 2
Argument..................................................................................... 15
Conclusion ................................................................................... 33
TABLE OF AUTHORITIES

Cases:
Al-Bihani v. Obama, 590 F.3d 866 (D.C. Cir. 2010),
cert. denied, 563 U.S. 929 (2011) ....................................... 32
B&B Hardware, Inc. v. Hargis Indus., Inc.,
135 S. Ct. 1293 (2015) ......................................................... 18
Callan v. Wilson, 127 U.S. 540 (1888) ................................. 23
Colepaugh v. Looney, 235 F.2d 429 (10th Cir. 1956),
cert. denied, 352 U.S. 1014 (1957) ..................................... 22
Collins v. Youngblood, 497 U.S. 37 (1990) .......................... 29
Hamdan v. Rumsfeld, 548 U.S. 557 (2006) ......2, 3, 20, 21, 22
Hamdan v. United States, 696 F.3d 1238
(D.C. Cir. 2012) ..................................................................... 7
Harisiades v. Shaughnessy, 342 U.S. 580 (1952) ............... 32
Marks v. United States, 430 U.S. 188 (1977) ...................... 25
Mathews v. Diaz, 426 U.S. 67 (1976) ................................... 31
Northern Pipeline Constr. Co. v. Marathon Pipe
Line Co., 458 U.S. 50 (1982) ............................................... 20
Pinkerton v. United States, 328 U.S. 640 (1946) ................ 14
Puckett v. United States, 556 U.S. 129 (2009) .............. 17, 18
Quirin, Ex parte, 317 U.S. 1 (1942) ..............12, 20, 21, 22, 23
United States v. Baucum, 80 F.3d 539
(D.C. Cir. 1996) ................................................................... 18
United States v. Cotton, 535 U.S. 625 (2002) ...................... 17
(III)

 IV
Cases—Continued:

Page

United States v. Ferreira, 275 F.3d 1020
(11th Cir. 2001) .................................................................... 31
United States v. Haddock, 956 F.2d 1534
(10th Cir.), cert. denied, 506 U.S. 828 (1992) ................... 28
United States v. Harcrow, 66 M.J. 154
(C.A.A.F. 2008).................................................................... 17
United States v. Marcus, 560 U.S. 258 (2010) .................... 28
United States v. Miranda, 780 F.3d 1185
(D.C. Cir. 2015) ................................................................... 17
United States v. Neuci-Peña, 711 F.3d 191
(1st Cir. 2013) ...................................................................... 18
United States v. Olano, 507 U.S. 725 (1993) ........... 16, 19, 27
United States v. Williams, 341 U.S. 58 (1951) ................... 17
Wellness Int’l Network, Ltd. v. Sharif,
135 S. Ct. 1932 (2015) ......................................................... 18
Wood v. Allen, 558 U.S. 290 (2010) ...................................... 28
Yakus v. United States, 321 U.S. 414 (1944) ....................... 28
Youngstown Sheet & Tube Co. v. Sawyer,
343 U.S. 579 (1952).............................................................. 20
Constitution and statutes:
U.S. Const.:
Art. I ........................................................................ passim
§ 8:
Cl. 1........................................................................ 20
Cl. 10 (Define and Punish Clause) ..... 11, 13, 18, 20
Cl. 11 (Declare War Clause) ......................... 11, 21
Cls. 11-14............................................................... 20
Cl. 18 (Necessary and Proper Clause)......... 20, 21
§ 9, Cl. 3 (Ex Post Facto Clause) .................... passim

 V
Constitution and statutes—Continued:

Page

Art. III ..................................................................... passim
§ 1 ............................................................................... 20
Amend. V .......................................................................... 23
Due Process Clause ................................6, 7, 12, 15, 30
Amend. VI ........................................................................ 23
Authorization for Use of Military Force,
Pub. L. No. 107-40, § 2(a), 115 Stat. 224 ............................. 2
Espionage Act, ch. 30, 40 Stat. 217 ...................................... 23
Military Commissions Act of 2006, 10 U.S.C. 948a
et seq. (2006) .......................................................................... 3
10 U.S.C. 948a .................................................................. 27
10 U.S.C. 948b(a) ............................................................... 3
10 U.S.C. 948d(a) ............................................................. 27
10 U.S.C. 950u.................................................................... 2
10 U.S.C. 950v(b)(1) .......................................................... 3
10 U.S.C. 950v(b)(2) .......................................................... 3
10 U.S.C. 950v(b)(24) ........................................................ 3
10 U.S.C. 950v(b)(25) ........................................................ 2
10 U.S.C. 950v(b)(28) .................................................... 2, 4
Military Commissions Act of 2009, 10 U.S.C. 948a
et seq. ...................................................................................... 4
10 U.S.C. 950p(b) ............................................................. 27
10 U.S.C. 950p(d) ............................................................. 27
Uniform Code of Military Justice, 10 U.S.C. 801
et seq. ...................................................................................... 2
10 U.S.C. 821 .......................................................... 2, 3, 8, 9
War Crimes Act of 1996, 18 U.S.C. 2441 et seq. ................. 23
18 U.S.C. 2332(b) (2000) ........................................................ 29

 VI
Miscellaneous:

Page

152 Cong. Rec. 20,727 (2006) ................................................ 27
Manual for Military Commissions (rev. ed. 2016) ........... 17

 In the Supreme Court of the United States
No. 16-1307
ALI HAMZA AHMAD SULIMAN AL BAHLUL, PETITIONER
v.
UNITED STATES OF AMERICA
ON PETITION FOR A WRIT OF CERTIORARI
TO THE UNITED STATES COURT OF APPEALS
FOR THE DISTRICT OF COLUMBIA CIRCUIT

BRIEF FOR THE UNITED STATES IN OPPOSITION

OPINIONS BELOW

The opinion of the court of appeals (Pet. App. 1-163)
is reported at 840 F.3d 757. Prior opinions of the court
of appeals (Pet. App. 165-301, 303-452) are reported at
792 F.3d 1 and 767 F.3d 1. The opinion of the United
States Court of Military Commission Review (Pet. App.
455-680) is reported at 820 F. Supp. 2d 1141.
JURISDICTION

The judgment of the court of appeals was entered on
October 20, 2016. A petition for rehearing was denied
on November 28, 2016 (Pet. App. 681). On February 2,
2017, the Chief Justice extended the time within which
to file a petition for a writ of certiorari to and including
March 28, 2017, and the petition was filed on that date.
The jurisdiction of this Court is invoked under 10 U.S.C.
950g(e) and 28 U.S.C. 1254(1).

(1)

 2
STATEMENT

Following a trial by military commission at Guantánamo Bay, Cuba, petitioner was convicted of conspiracy
to commit offenses triable by military commission, in violation of 10 U.S.C. 950v(b)(28) (2006); solicitation of
others to commit offenses triable by military commission, in violation of 10 U.S.C. 950u (2006); and providing
material support for terrorism, in violation of 10 U.S.C.
950v(b)(25) (2006). Pet. App. 461-462. Petitioner was
sentenced to life imprisonment. Id. at 461. The United
States Court of Military Commission Review (USCMCR)
affirmed. Id. at 455-680. The court of appeals affirmed
petitioner’s conspiracy conviction and reversed petitioner’s convictions for solicitation and providing material support for terrorism. Id. at 1-163, 165-301, 303-452.
1. On September 11, 2001, the al Qaeda terrorist organization attacked the United States and killed nearly
3000 people. Pet. App. 472; 11/2/15 Gov’t C.A. Br. 4. In
response, Congress authorized the President to use “all
necessary and appropriate force against those nations,
organizations, or persons he determines planned, authorized, committed, or aided the terrorist attacks that
occurred on September 11, 2001.” Authorization for Use
of Military Force, Pub. L. No. 107-40, § 2(a), 115 Stat.
224. The President issued a military order authorizing
military commissions to try non-citizens for certain offenses. Pet. App. 307.
In Hamdan v. Rumsfeld, 548 U.S. 557 (2006), this
Court held that the military commission system the
President established contravened statutory restrictions
on military commission procedures in the Uniform Code
of Military Justice, 10 U.S.C. 801 et seq. 548 U.S. at 613633, 635. The Court divided over whether 10 U.S.C. 821,

 3
which creates military commission jurisdiction over offenses that “by statute or by the law of war may be tried
by military commissions,” ibid., authorized military
commissions to try conspiracy to violate the law of war,
see Hamdan, 548 U.S. at 595-613 (opinion of Stevens,
J.) (concluding that Section 821 did not authorize trial
for conspiracy); id. at 697-706 (Thomas, J., dissenting)
(concluding that Section 821 authorized trial for conspiracy); see also id. at 655 (Kennedy, J., concurring in
part) (declining to address the question).
Four Justices joined opinions inviting Congress to
clarify the authority of military commissions. See Hamdan, 548 U.S. at 636 (Breyer, J., concurring) ( joined by
Kennedy, Souter, and Ginsburg, JJ.) (“Nothing prevents the President” from seeking from Congress “legislative authority to create military commissions of the
kind at issue here.”); id. at 655 (Kennedy, J., concurring
in part) (stating that “Congress may choose to provide
further guidance” regarding the “validity of the conspiracy charge” and that “Congress, not the Court, is the
branch in the better position to undertake the ‘sensitive
task of establishing a principle not inconsistent with the
national interest or with international justice’ ”) (citation omitted).
In response, Congress enacted the Military Commissions Act of 2006 (2006 MCA), 10 U.S.C. 948a et seq.
(2006). The 2006 MCA established a military commission system “to try alien unlawful enemy combatants
engaged in hostilities against the United States for violations of the law of war and other offenses triable by
military commission.” 10 U.S.C. 948b(a) (2006). It codifies a number of specific war crimes, including murder
of protected persons, attacking civilians, and terrorism.
See 10 U.S.C. 950v(b)(1), (2), and (24) (2006). The 2006

 4
MCA also prohibits conspiring to commit one or more
of the codified substantive offenses, by making it unlawful to “conspire[] to commit one or more substantive offenses triable by military commission under this chapter”
if the person charged “knowingly does any overt act to
effect the object of the conspiracy.” 10 U.S.C. 950v(b)(28)
(2006). 1
2. Petitioner, a native of Yemen, went to Afghanistan in the late 1990s to join al Qaeda. Pet. App. 305.
He swore an oath of loyalty to Osama bin Laden and
received paramilitary training at an al Qaeda camp. Id.
at 305-306. Bin Laden assigned petitioner to work in al
Qaeda’s media office and later appointed petitioner as
his personal secretary. Id. at 306. Petitioner assisted
bin Laden in preparing public statements and operated
bin Laden’s communications equipment. Ibid.; 11/2/15
Gov’t C.A. Br. 6.
Bin Laden directed petitioner to create an al Qaeda
recruitment video highlighting the October 2000 attack
on the USS Cole that killed 17 American sailors. Pet. App.
306. Petitioner’s video, which called on viewers to execute terrorist attacks against the United States and to
come to Afghanistan for training, was used in al Qaeda
camps to motivate recruits and was distributed widely
outside Afghanistan. Ibid.; see 11/2/15 Gov’t C.A. Br. 6.
In Afghanistan, petitioner lived in the same house as
Muhamed Atta and Ziad al Jarrah, both of whom later
piloted aircraft in the 9/11 attacks. Pet. App. 306; 11/2/15
Gov’t C.A. Br. 6-7. Petitioner arranged for the two hijackers’ oaths of loyalty to bin Laden. Pet. App. 306.
Congress replaced the 2006 MCA with the Military Commissions Act of 2009, 10 U.S.C. 948a et seq., but left the conspiracy provision and other provisions relevant here substantively intact. See
Pet. App. 307 n.1.
1

 5
Petitioner volunteered to participate in the 9/11 attacks
himself, but bin Laden refused permission because he
considered petitioner’s media activities too important.
Ibid. Just before the 9/11 attacks, petitioner traveled
to a remote region of Afghanistan with bin Laden,
where he operated the radio that bin Laden used to
track news of the attacks. Ibid.
Petitioner then fled to Pakistan, where he was captured in December 2001. Pet. App. 306. Petitioner was
turned over to U.S. custody, and was later detained at
the U.S. naval base at Guantánamo Bay, Cuba. Ibid.
3. In 2008, military authorities charged petitioner
under the 2006 MCA with conspiracy to commit war
crimes, solicitation of others to commit war crimes, and
providing material support for terrorism. Pet. App.
309. The substantive offenses underlying the conspiracy charge were 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. Ibid. Military prosecutors alleged
that petitioner committed 11 overt acts in furtherance
of the conspiracy. Id. at 309-310. These included undergoing military-type training at an al Qaeda camp,
swearing loyalty to bin Laden and performing personal
services for bin Laden, preparing the USS Cole video,
carrying weapons and a suicide belt to protect bin
Laden, arranging for two of the 9/11 hijackers to swear
loyalty to bin Laden, “prepar[ing] the propaganda declarations styled as martyr wills of Atta and al Jarrah in
preparation for the acts of terrorism perpetrated by
[them] and others at various locations in the United

 6
States on September 11, 2001,” and operating data-processing and communications equipment for bin Laden
and others. Id. at 310 n.2; see id. at 309.
During pretrial hearings, petitioner declared that he
would boycott the proceedings. Pet. App. 309. Petitioner’s appointed counsel, following petitioner’s instructions, explicitly waived all pretrial motions. Ibid.; see
11/2/15 Gov’t C.A. Br. 8. Petitioner pleaded not guilty
but admitted all of the factual allegations against him,
except for the allegation that he wore a suicide belt to
protect bin Laden. Pet. App. 309.
At trial, petitioner instructed his counsel not to present a defense. Pet. App. 309; 11/2/15 Gov’t C.A. Br. 9.
Petitioner did not cross-examine government witnesses,
object to the prosecution’s evidence, or make opening or
closing arguments. Ibid. Petitioner did not argue that
Congress lacked authority under the Constitution to try
him for conspiracy in a military commission, nor did he
claim that his military commission trial violated the Ex
Post Facto Clause, Article III, or the equal protection
component of the Due Process Clause. Pet. App. 311,
314-315, 664, 668; see 11/2/15 Gov’t C.A. Br. 9.
The military commission convicted petitioner of all
the charges. Using a detailed worksheet of findings, the
commission specifically found that petitioner conspired
to commit each of the seven object offenses, including
murder of protected persons and attacking civilians.
Pet. App. 309. The commission also found that petitioner committed each of the alleged overt acts, except
for wearing a suicide belt to protect bin Laden. Id. at
309-310 & n.2.
The military commission sentenced petitioner to life
imprisonment, and the convening authority approved

 7
the findings and sentence. Pet. App. 310. The USCMCR
affirmed. Id. at 455-679.
4. Petitioner’s appellate counsel filed a petition for
review in the court of appeals, arguing, inter alia, that
petitioner’s military commission convictions violated
Article I and Article III of the Constitution, the Ex Post
Facto Clause, and the equal protection component of
the Due Process Clause. 2 Pet. App. 311, 354. While petitioner’s appeal was pending, the D.C. Circuit held
in Hamdan v. United States, 696 F.3d 1238 (2012)
(Hamdan II), that the 2006 MCA did not authorize
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.” Id. at 1248; see Pet. App. 311. The
government conceded that the panel was required to vacate petitioner’s convictions under the 2006 MCA in
light of Hamdan II. Pet. App. 311. Based on that concession, the panel vacated petitioner’s convictions.
Ibid. 3
While petitioner’s appeal was pending in the court of appeals,
petitioner wrote a letter to the court stating that he had never authorized the appeal and that he wanted it withdrawn. C.A. Doc. No.
1434449 (May 2, 2013). The court ordered petitioner’s counsel to
obtain written authorization for the appeal. C.A. Doc. No. 1436058
(May 14, 2013). Counsel was unable to obtain written authorization,
but represented that petitioner had orally authorized the appeal. As
described by counsel, that authorization was limited to litigation in
the court of appeals and did not extend to seeking this Court’s review. See C.A. Doc. No. 1443565, at 3-5 (June 26, 2013).
3
Petitioner is mistaken in stating (Pet. 10) that the government
“notified the Circuit of its intention to seek certiorari in petitioner’s
case to have Hamdan II overturned” but then sought rehearing en
banc instead. In conceding that Hamdan II required vacatur of petitioner’s convictions, the government stated more generally that it
2

 8
5. The court of appeals granted rehearing en banc,
vacated petitioner’s solicitation and material support
convictions, rejected petitioner’s statutory and ex post
facto challenges to his conspiracy conviction, and remanded the case to the panel for consideration of petitioner’s remaining challenges to his conspiracy conviction. Pet. App. 303-355. The en banc court overruled
Hamdan II, holding that the 2006 MCA unambiguously
provided military commission jurisdiction to adjudicate
charges arising out of conduct forbidden under the statute
regardless of whether the conduct took place before or
after the statute was enacted. Id. at 317-323.
The court of appeals then turned to petitioner’s constitutional ex post facto claim, which it held was subject
to plain-error review. Pet. App. 311-315. The court explained that petitioner had “forfeited the arguments” he
raised under the Ex Post Facto Clause by “flatly refus[ing] to participate in the military commission proceedings and instruct[ing] his trial counsel not to present a substantive defense.” Id. at 314-315. The court
acknowledged that petitioner “objected to the commission’s authority to try him” but held that petitioner’s
blanket objections, which were “couched entirely in political and religious terms,” were “too general” to preserve his legal claims. Id. at 315 (citation omitted).
The court of appeals rejected petitioner’s ex post
facto challenge to his conspiracy conviction on the ground
that it was not “plain” that conspiracy was “not already
triable” at the time of petitioner’s conduct under the
“law of war” as incorporated in 10 U.S.C. 821. Pet. App.
330; see id. at 328-346. The court noted that this Court
was “preserv[ing] [its] arguments for further review,” without specifying whether it intended to seek en banc review or a writ of certiorari. 1/9/13 Gov’t C.A. Supp. Br. 1.

 9
in Hamdan “debated * * * at length” whether conspiracy was an offense under the “law of war” as incorporated in Section 821, without ultimately resolving the
question. Id. at 338. It further observed that there was
domestic precedent for treating conspiracy as a law-ofwar offense triable by military commission and that decisions of this Court indicated “that domestic precedent
is an important part of ” the law-of-war inquiry. Id. at
340; see id. at 344-346. The court of appeals therefore
concluded that, at a minimum, it was not plain that conspiracy was not triable by military commission at the
time of petitioner’s conduct. In contrast, the court
found a plain Ex Post Facto Clause violation in trying
petitioner under the 2006 MCA for providing material
support for terrorism and solicitation. Id. at 346-354.
The en banc court remanded the case to the panel to
consider, inter alia, petitioner’s Article I, Article III,
and equal protection claims. Id. at 354-355.
Judge Henderson concurred, writing that she would
have affirmed petitioner’s conspiracy conviction against
his ex post facto challenge for the additional reason that
it is not plain that the Ex Post Facto Clause applies to
alien unlawful enemy combatants detained at Guantánamo Bay. Pet. App. 356-360.
Judge Rogers concurred in the judgment in part and
dissented in part. Pet. App. 361-393. She applied de
novo review to petitioner’s claims, concluded that the
2006 MCA did not authorize petitioner’s trial for conspiracy, and concluded that if the 2006 MCA did authorize trying petitioner on conspiracy charges, it violated
the Ex Post Facto Clause. Id. at 386-393.
Judge Brown and Judge Kavanaugh each authored
opinions concurring in the judgment in part and dis-

 10
senting from the decision to remand the Article I, Article III, and equal protection claims to the panel. Pet.
App. 394-417, 418-452. They would have rejected all of
petitioner’s challenges to his conspiracy conviction, applying de novo review. Ibid.
6. On remand, a divided panel vacated petitioner’s
conspiracy conviction, concluding that a military tribunal could not try petitioner for conspiring to violate the
law of war without “violat[ing] the separation of powers
enshrined in Article III.” Pet. App. 205; see id. at 165205. Judge Rogers, joined by Judge Tatel, applied de
novo review to petitioner’s Article III claim on the ground
that an Article III challenge was “a structural objection” that “cannot be forfeited.” Id. at 167; see id. at
168-174. The panel majority reasoned that Article III
generally requires judicial power to be exercised in Article III courts. Id. at 175. It acknowledged that military tribunal prosecutions are an exception. Id. at 175176. But the panel held that the exception extended
only to offenses that are internationally recognized as
violations of the law of war—a category that the government had conceded did not presently reach inchoate
conspiracy to commit war crimes. Id. at 176-180.
Judge Tatel concurred. Pet. App. 206-215. He noted
that he joined both the en banc opinion affirming petitioner’s conspiracy conviction against statutory and ex
post facto challenges on plain-error review, and the
panel opinion concluding that petitioner’s conspiracy violated Article III based on de novo review. He wrote
that his decisions were explained by the different standards of review. Ibid.
Judge Henderson dissented. Pet. App. 216-301. She
argued that petitioner’s claims were subject to plainerror review and that petitioner’s challenges lacked

 11
merit under both plain-error and de novo standards.
Ibid.
7. The court of appeals granted rehearing en banc,
vacated the panel opinion and affirmed petitioner’s conspiracy conviction by a 6-3 vote in a per curiam order.
Pet. App. 1-4. The order explained that four judges
“would affirm because they conclude that, consistent
with Articles I and III of the Constitution, Congress
may make conspiracy to commit war crimes an offense
triable by military commission.” Id. at 3. It explained
that Judge Millett “would apply plain error review and
affirm [petitioner’s] conviction under that standard”
without reaching “whether Congress may make inchoate conspiracy an offense triable by military commission.” Ibid. Finally, the order explained that Judge
Wilkins would also decline to reach petitioner’s broad
constitutional claim, and would affirm because “particular features of [petitioner’s] conviction demonstrate that
[petitioner] was not convicted of an inchoate conspiracy
offense.” Id. at 3-4.
a. Members of the majority elaborated on their
views in separate opinions.
i. Judge Kavanaugh, joined by Judges Brown and
Griffith, wrote in a concurring opinion that Congress
has the power under Article I to authorize military tribunals to try conspiracies to commit war crimes, even
though conspiracy is not recognized as a violation of international law. Pet. App. 5-35. He wrote that Congress’s power to establish military commissions derives
not only from its power to “define and punish * * * Offences against the Law of Nations,” U.S. Const. Art. I,
§ 8, Cl. 10, but also from its power to “declare War,”
U.S. Const. Art. I, § 8, Cl. 11, and from the other warpowers clauses in Article I. Pet. App. 9-11 (Kavanaugh,

 12
J., concurring). The war powers, he explained, “do not
refer to international law or otherwise impose international law as a constraint on Congress’s authority to
make offenses triable by military commission.” Id. at 11.
Judge Kavanaugh found history and precedent supported the conclusion that Congress could authorize
military tribunals to try enemy combatants for conspiracy to commit war crimes, even though inchoate conspiracy is not an offense recognized under international
law. Pet. App. 11-23 (Kavanaugh, J., concurring). This
Court’s “leading constitutional decision regarding military commissions,” he explained, had noted in particular that military commissions have long tried the offense of spying, which is not a violation of the international law of war. Id. at 13. Judge Kavanaugh also
pointed to the “deeply rooted history of U.S. military
commission trials of the offense of conspiracy,” including the “two most important military commission precedents in U.S. history—the trials of the Lincoln conspirators and the Nazi saboteurs” in Ex parte Quirin,
317 U.S. 1 (1942). Pet. App. 18-19 (Kavanaugh, J., concurring). Because military tribunals operate as an exception to the rule that the judicial power must be exercised in Article III courts, Judge Kavanaugh wrote, historical practice confirms that “Article III is not a barrier to U.S. military commission trials” for conspiracy.
Id. at 25.
Judge Kavanaugh also rejected petitioner’s claim
that the 2006 MCA violates the equal protection component of the Due Process Clause by authorizing military
commission trials of alien enemy combatants but not enemy combatants who are U.S. citizens. Pet. App. 27 n.12
(Kavanaugh, J., concurring). Judge Kavanaugh incorporated the relevant portion of his opinion from the

 13
prior en banc proceeding, ibid., which explained that
“federal laws drawing distinctions between U.S. citizens and aliens—particularly in the context of war and
national security”—are permissible when “rationally
related to a legitimate governmental interest,” and 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.” Id. at 442 (Kavanaugh, J., concurring
in the judgment in part and dissenting in part) (citation
omitted).
ii. Judge Henderson concurred, incorporating by
reference her dissent from the panel opinion, in which
she concluded that petitioner had forfeited his claims
and that, in any event, Congress may constitutionally
provide for a trial of conspiracies to commit war crimes
before military commissions in light of its powers under
the Define and Punish Clause and the war-powers
clauses in Article I. Pet. App. 5; see id. at 218, 247-284
(Henderson, J., dissenting).
iii. Judge Millett concurred, explaining that she
would affirm by applying plain-error review. Pet. App.
36-81. She concluded that petitioner was not convicted
of “ordinary inchoate conspiracy,” but of a “carefully
crafted form of statutory conspiracy that, on the record
of this case, resembles in important ways * * * forms
of conspiracy or collective action” recognized under international law. Id. at 73. Judge Millett emphasized
that petitioner’s conviction involved completed object
offenses that were recognized under the international
law of war, that the commission found that petitioner
personally intended that every element of the object offenses be committed, and that the commission found

 14
that petitioner committed overt acts that were directly
tied to “al Qaeda’s waging of terrorist aggression
against the United States.” Id. at 68; see id. at 65-67.
She explained that those elements made petitioner’s
conspiracy conviction analogous to forms of liability recognized under international law, including liability for
joint criminal enterprise and conspiracy to commit aggressive war or genocide. Id. at 67-73. Judge Millett
concluded that “any delta between [petitioner’s] conspiracy offense and those offenses that international
law proscribes is too narrow to rise to the level of plain
constitutional error.” Id. at 67. Judge Millett concluded, in the alternative, that the historical practice of
trying conspiracy in U.S. military commissions “make[s]
it far from plain that conspiracy under the 2006 [MCA]
would not be triable by military commission.” Id. at 76.
Judge Millett also rejected petitioner’s equal protection
challenge on the ground that “no relevant precedent
plainly supports the application of equal protection
principles” to “foreign enemy combatants.” Id. at 80.
iv. Judge Wilkins also concurred. Pet. App. 82-96.
He reasoned that the military commission’s findings regarding petitioner’s role were sufficient to establish liability for the war crimes of petitioner’s co-conspirators
on 9/11 under Pinkerton v. United States, 328 U.S. 640
(1946). Pet. App. 89-93 (Wilkins, J., concurring). Judge
Wilkins concluded that because the internationally recognized offense of joint criminal enterprise has essentially the same requirements as Pinkerton liability, “the
factual elements that were proven during [petitioner’s]
prosecution were indistinguishable from a theory recognized under international law.” Id. at 94. He thus
saw no occasion to determine whether Congress could
make inchoate conspiracy an offense triable by military

 15
tribunal. Judge Wilkins also rejected petitioner’s equal
protection argument for the reasons in Judge Millett’s
opinion. Id. at 96.
b. Judges Rogers, Tatel, and Pillard filed a joint dissent. Pet. App. 97-163. They would have applied de
novo review because, in their view, the court at least had
discretion to consider a structural Article III claim not
raised below and should do so in this case. Id. at 98-106.
The dissenting judges acknowledged that Article III
does not bar military commissions from exercising jurisdiction over law-of-war offenses, but they argued
that such jurisdiction may extend only to offenses that
are recognized under customary international law. Id.
at 106-140. Rejecting the views of Judges Millett and
Wilkins, they concluded that the military commission
findings in petitioner’s case did not suffice to establish
liability for an internationally recognized law-of-war offense. Id. at 146-157. Finally, the dissenting judges
noted that, because the votes of judges applying plainerror review or relying on case-specific grounds were
necessary for affirmance, the court of appeals’ decision
“provides no precedential value” for trying inchoate
conspiracy in a military commission. Id. at 162.
ARGUMENT

Petitioner renews (Pet. 14-29) his contentions that
his conviction by a military commission for conspiracy
to commit war crimes should be vacated based on Article I, Article III, the Ex Post Facto Clause, and the
equal protection component of the Due Process Clause
of the Constitution. The court of appeals correctly rejected these challenges, and its judgment on each constitutional claim rested on case-specific grounds, application of plain-error review, or both. The court of appeals also correctly rejected petitioner’s statutory claim

 16
(Pet. 22) that the 2006 MCA was not intended to have
retroactive application. The decision below does not
conflict with any decision of this Court or any other
court of appeals. And petitioner’s case would be a poor
vehicle for considering petitioner’s broad challenges because each of petitioner’s constitutional claims falters
on the narrow, case-specific grounds on which the judgment rests. Further review is unwarranted.
1. Petitioner first contends (Pet. 14-20) that this
Court should vacate his conviction on the ground that
Congress may not, under its Article I war powers and
consistent with Article III, codify conspiracy to commit
war crimes as an offense triable by military commission.
This claim lacks merit and does not warrant further review.
a. i. Petitioner’s challenge under Article I and Article III is properly reviewed for plain error, because
petitioner did not raise his claim before the military
commission. While petitioner objected to the commission proceedings, his remarks were “couched entirely in
political and religious terms” and were “unquestionably
too general to have alerted the trial court to the substance” of the claims later raised on appeal. Pet. App.
315 (citation and internal quotation marks omitted); see
id. at 46 (Millett, J., concurring). Petitioner’s claim is
therefore subject to the well-established principle “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) (citation and internal
quotation marks omitted).
Petitioner contends (Pet. 30) that plain-error review
should not apply because it serves no purpose in the

 17
context of “pure questions of law.” But this Court has
repeatedly held that important purposes underlie the
plain-error rule, including promoting finality and diminishing opportunities and incentives for gamesmanship.
See, e.g., Puckett v. United States, 556 U.S. 129, 134
(2009); see also Pet. App. 44-45 (Millett, J., concurring).
Petitioner is also mistaken in contending (Pet. 30-31)
that the plain-error rule does not apply in military commissions. Military courts, including the USCMCR in
this case, have held that “principles of ‘waiver’ and
‘forfeiture’ ” are “applied in U.S. Courts and CourtsMartial.” Pet. App. 666; see United States v. Harcrow,
66 M.J. 154, 157-159 (C.A.A.F. 2008); cf. Manual for
Military Commissions R. 801(g), at II-70 (rev. ed. 2016)
(failure to timely raise claims constitutes waiver).
Nor are forfeiture principles inapplicable on the
ground that petitioner raises structural challenges to
the commission’s subject-matter jurisdiction. See Pet.
App. 7 n.1 (Kavanaugh, J., concurring); id. at 82 (Wilkins, J., concurring); id. at 100-101 (Rogers, J., dissenting). Nonwaivable jurisdictional limitations are those
concerning “the courts’ statutory or constitutional
power to adjudicate the case.” United States v. Cotton,
535 U.S. 625, 630 (2002) (citation and emphasis omitted).
Here, there is no dispute that Congress conferred on
military commissions the power to try conspiracy offenses. Petitioner instead argues that Congress exceeded its Article I powers by making conspiracy a
crime tried by military tribunal. But “the unconstitutionality of the statute under which the proceeding is
brought does not oust a court of jurisdiction.” United
States v. Williams, 341 U.S. 58, 66 (1951). Courts have
accordingly treated claims that Congress lacked authority to create jurisdiction over a particular type of

 18
offense as waivable. See, e.g., United States v. Miranda,
780 F.3d 1185, 1188-1190 (D.C. Cir. 2015) (challenge to
enactment under Define and Punish Clause was not
challenge to subject-matter jurisdiction); United States
v. Neuci-Peña, 711 F.3d 191, 197 (1st Cir. 2013) (same);
United States v. Baucum, 80 F.3d 539 (D.C. Cir. 1996)
(per curiam); see also Pet. App. 48 (Millett, J., concurring); Pet. App. 219-238 (Henderson, J., dissenting).
And this Court has itself twice treated claims that Congress had conferred powers on an Article I tribunal in a
manner that violated Article III as subject to forfeiture.
See Wellness Int’l Network, Ltd. v. Sharif, 135 S. Ct.
1932, 1949 (2015) (remanding case to court of appeals
for determination of whether petitioner had forfeited an
Article III claim); B&B Hardware, Inc. v. Hargis Indus.,
Inc., 135 S. Ct. 1293, 1304 (2015) (declining to consider
Article III objection because the argument had been
abandoned by petitioner and therefore “is not before
us”); see also Pet. App. 49-52 (Millett, J., concurring).
Even if the Court would have discretion to disregard
petitioner’s forfeiture of his Article I and Article III
claims, that course would not be warranted. Equitable
principles do not support that result: Petitioner, who
was represented by counsel, has never suggested he
faced any obstacle to pressing before the tribunal the
claims that he forfeited there. Instead, petitioner made
a deliberate choice to forgo any legal challenges in service of a self-styled boycott. And here as in other cases,
the requirement that a litigant raise his claim at trial is
important because it permits the adverse party and the
tribunal to respond with steps to ensure that the alleged
error “cannot possibly affect the ultimate outcome,”
Pet. App. 45 (Millett, J., concurring) (quoting Puckett,
556 U.S. at 134). Here, for instance, prosecutors would

 19
have had the opportunity to reassess whether to seek
an amendment of the charges to also allege substantive
offenses based on Pinkerton principles.
Moreover, as Judge Millett observed, “[t]he separation of powers should counsel the greatest judicial hesitation” regarding undertaking review of a forfeited
claim “when the Political Branches are jointly exercising their judgment in areas of national security, the conduct of war, and foreign relations.” Pet. App. 62 (Millett,
J., concurring). That is particularly so when there is no
structural impediment to any future litigant raising a
challenge of the type that petitioner forfeited, see id. at
53 (contrasting criminal cases with civil cases, which
“can pose the risk of parties colluding and consenting to
a non-Article III forum for resolution of their dispute”),
and where it is unclear whether a decision on petitioner’s forfeited claims would in fact provide controlling guidance for future proceedings, because of casespecific findings as to liability in petitioner’s case, see
id. at 72-73; id. at 90-93 (Wilkins, J., concurring); pp. 2324, infra, and because it is not clear to what extent future prosecutions under the 2006 MCA would rest on
pure inchoate conspiracy, see pp. 25-26, infra.
ii. Petitioner cannot demonstrate error under Article I and Article III, let alone plain error, in his trial
before a military commission for conspiracy to commit
war crimes. See Olano, 507 U.S. at 732-735 (explaining
that a defendant may obtain relief for a forfeited claim
only by demonstrating that an error was “plain,” “affect[ed his] substantial rights,” and “seriously affects
the fairness, integrity, or public reputation of judicial
proceedings”) (brackets and citations omitted).
When Congress codified conspiracy to commit war
crimes as an offense in the 2006 MCA, it responded in a

 20
manner that is consistent with the constitutional structure to this Court’s invitation that the political Branches
clarify military commission jurisdiction over conspiracy
offenses, see Hamdan v. Rumsfeld, 548 U.S. 557, 636
(2006) (Breyer, J., concurring); id. at 655 (Kennedy, J.,
concurring in part). While Article III vests the federal
courts with “[t]he judicial Power of the United States,”
U.S. Const. Art. III, § 1, that Article is “interpreted in
light of the historical context in which the Constitution
was written, and of the structural imperatives of the
Constitution as a whole.” Northern Pipeline Constr.
Co. v. Marathon Pipe Line Co., 458 U.S. 50, 64 (1982)
(opinion of Brennan, J.). Applying those principles, this
Court has upheld Article I tribunals in a variety of areas,
including in the context of military tribunals established
as an exercise of Congress’s war powers and its powers
under the Define and Punish Clause. See Ex parte Quirin, 317 U.S. 1, 40 (1942).
Under those principles, Congress acted permissibly
when—acting in concert with the President, see Youngstown Sheet & Tube Co. v. Sawyer, 343 U.S. 579, 635-638
(1952) (Jackson, J., concurring in the judgment and
opinion of the Court)—it made the offense of conspiracy
to commit war crimes triable by military commission.
The Constitution confers on Congress war powers that
include not only the power to define and punish offenses
against the law of nations, but also the power to declare
war and other war powers, U.S. Const. Art. I, § 8, Cls. 1,
11-14, and to “make all Laws which shall be necessary
and proper for carrying into Execution the foregoing
Powers,” U.S. Const. Art. I, § 8, Cl. 18. Those grants of
power support Congress’s authority to confer jurisdiction on military commissions to try alien unlawful enemy combatants for conspiracy to commit war crimes.

 21
See Hamdan, 548 U.S. at 592 n.21 (“ ‘[I]n general, it is
those provisions of the Constitution which empower
Congress to ‘declare war’ and ‘raise armies,’ and which,
in authorizing the initiation of war, authorize the employment of all necessary and proper agencies for its
due prosecution, from which [the military commission]
derives its original sanction.’ ”) (citation and emphasis
omitted; brackets in original); Quirin, 317 U.S. at 25-26
(enumerating Congress’s war powers as sources of authority to establish military commissions); see also Pet.
App. 11 (Kavanaugh, J., concurring). And, notably, the
Declare War Clause, the other war-powers clauses, and
the Necessary and Proper Clause do not even arguably
“refer to international law” or suggest that the powers
they describe may be exercised only in a manner supported by an international consensus. See Pet. App. 10
(Kavanaugh, J., concurring).
Historical practice confirms that Congress may validly confer on military tribunals the authority to try
conspiracies to commit war crimes, even though conspiracy itself has not attained international recognition
at this time as an offense under customary international
law. Since the Founding, Congress and the President
have given military tribunals jurisdiction to try offenses
that were not violations of international law—including
spying and aiding the enemy. See Pet. App. 16-17 (Kavanaugh, J., concurring). And of particular relevance,
military commissions have long charged defendants
with conspiracy to commit war crimes. Far from reflecting only “isolated episodes” that do not “deserve to
be given any precedential value” (Pet. 19), these precedents include “the two most important military commission precedents in U.S. history”—those involving the
Lincoln conspirators and the Nazi saboteurs in Quirin.

 22
Pet. App. 19 (Kavanaugh, J., concurring); see Hamdan,
548 U.S. at 699 (Thomas, J., dissenting); see also
Colepaugh v. Looney, 235 F.2d 429, 431 (10th Cir. 1956),
cert. denied, 352 U.S. 1014 (1957). 4
Petitioner argues (Pet. 17) that Quirin actually required that an offense be internationally recognized as
a law-of-war offense in order to be tried by a U.S. military tribunal. But in determining that the defendants
could be tried in Article I tribunals, Quirin cited authorities that expressly rejected the proposition that
spying was a violation of international law, see 317 U.S.
at 30-31 nn.7-8; see Pet. App. 15 (Kavanaugh, J., concurring), before determining, based on “the practice of our
own military authorities before the adoption of the Constitution, and during the Mexican and Civil Wars,” that
in the United States, spying and sabotage were subject
to trial before military commission, Quirin, 317 U.S. at
at 31 (footnote omitted); see id. at 31-33 & nn.9-10, 42 &
n.14; Pet. App. 15 (Kavanaugh, J., concurring). Quirin
thus interpreted the category of “offenses against the
law of war” that may be tried by military tribunals as
including offenses that were not violations of international law, but were triable by military commissions under domestic practice. 317 U.S. at 32 n.10.
Petitioner also asserts that Quirin “strongly suggested, if not implicitly held” that conspiracy cannot be
tried by military commission because conspiracy is an

That history also refutes petitioner’s suggestion that military
commissions have traditionally been limited to providing “swift justice * * * on the battlefield.” Pet. 14 (citation omitted). The commission in Quirin was held in Washington, D.C., 317 U.S. at 23, and
the proceedings in Colepaugh were conducted in New York, 9/17/14
Gov’t C.A. Br. 59.
4

 23
offense that was “traditionally triable by jury at common law.” Pet. 18 (citation omitted). In fact, Quirin
refutes petitioner’s contention that there cannot be concurrent jurisdiction between federal courts and military
commissions, because it noted that the fact that the Espionage Act, ch. 30, 40 Stat. 217, authorized trials in federal court for similar conduct did not limit the concurrent jurisdiction of the military commission. 317 U.S. at
27. No other portion of Quirin suggests that the existence of federal criminal jurisdiction divests a military
commission of jurisdiction over an offense that is also
cognizable under federal law as a war crime. If that
were so, the War Crimes Act of 1996, 18 U.S.C. 2441 et
seq., would largely foreclose law-of-war military commission jurisdiction over most of the offenses enumerated in the 2006 MCA. In addition, the offense at issue
in this case is not common law conspiracy but conspiracy to violate the law of war by an unlawful enemy combatant. Article III courts have never exercised exclusive jurisdiction over such conduct. 5 Petitioner’s arguments fail to establish error, let alone plain error, in the
military commissions’ exercise of jurisdiction under the
2006 MCA.
iii. Moreover, as the concurrences indicate, petitioner would also be unable to demonstrate plain error
in his case because of the 2006 MCA’s limitations on
Petitioner’s reliance (Pet. 18) on Callan v. Wilson, 127 U.S. 540
(1888), is misplaced. Callan held that the conspiracy offense in that
case was not a petty offense and accordingly required a jury trial.
Id. at 555, 557. That holding has nothing to do with the scope of
military commission jurisdiction. Petitioner contends (Pet. 18) that
Quirin “placed special emphasis” on Callan, but the Quirin Court
cited Callan only for the proposition that the Fifth and Sixth
Amendments did not expand the right to a jury trial beyond Article
III’s jury trial right.
5

 24
conspiracy and the specific findings of the military commission at his trial. The 2006 MCA requires, at a minimum, that the defendant personally commit an overt act
in furtherance of the alleged conspiracy. See Pet. App.
91 (Wilkins, J., concurring). In addition, petitioner was
convicted of conspiracy with respect to offenses that
were consummated—those in the 9/11 attacks, id. at 9091—with the military commission making detailed findings regarding overt acts that petitioner performed, including findings as to petitioner’s “intricate[] involve[ment] in preparing two 9/11 perpetrators for their attacks,” id. at 72 (Millett, J., concurring); see id. at 91-93
(Wilkins, J., concurring). A conspiracy conviction under
these circumstances “resembles in important ways
those forms of conspiracy or collective action that get
the international-law nod of approval.” Id. at 73 (Millett, J., concurring); see id. at 69-70 (explaining that “international law permits conviction for joint criminal enterprise where ‘a plurality of persons participat[es] in
the criminal plan’; there is ‘a common purpose which
amounts to or involves the commission of a crime’; and
‘the accused[] participat[es] in the common design’ ”)
(citation omitted; brackets in original); cf. id. at 94 (Wilkins, J., concurring) (“[T]he factual elements that were
proven during [petitioner’s] prosecution were indistinguishable from a theory recognized under international
law.”); id. at 410 (Brown, J., concurring in the judgment
in part and dissenting in part) (“Even if the offense of
conspiracy was not recognized under international law
in 2001 by the same labels used by Congress in the [2006
MCA], the substance is similar.”). At minimum, under
these circumstances, petitioner would be unable to
demonstrate that his military commission conviction reflected plain error.

 25
b. Petitioner errs in contending (Pet. 14-16) that this
Court should grant review of the judgment rejecting his
Article I and Article III claims, on the ground that
whether Congress may authorize military tribunals to
try conspiracies to commit war crimes is an issue of exceptional importance. That question does not warrant
review in this case because the court below did not resolve that question. Members of the court whose votes
were necessary to the judgment rejected petitioner’s
challenges based on plain-error principles, Pet. App. 3681 (Millett, J., concurring), or case-specific features of
petitioner’s case, id. at 82-96 (Wilkins, J., concurring);
see Marks v. United States, 430 U.S. 188, 193 (1977)
(the holding of a case that lacks a majority opinion is the
“position taken by those [ judges] who concurred in the
judgment[] on the narrowest grounds”) (citation omitted).
Petitioner’s suggestion that this Court should grant
review to consider a constitutional question not decided
below is particularly mistaken because the contours of
conspiracy charges in future military commission cases
are not apparent. In the military commission prosecution of Khalid Shaikh Mohammad and other alleged perpetrators of the 9/11 attacks, for example, the Chief
Prosecutor of Military Commissions has agreed to an
instruction that in order to convict the defendant of conspiracy, the panel must also find the defendant guilty of
one of the conspiracy’s object offenses. See Gov’t Second
Supp. Resp. to Defense Mot. to Dismiss for Lack of Jurisdiction at 1, United States v. Mohammad, No. AE 107A
(Aug. 27, 2014). This Court need not grant review here

 26
to address an abstract question that was not decided below, and the application of which to future cases is uncertain. 6
Moreover, as the judgment below illustrates, this
case would be an unsuitable vehicle for resolving petitioner’s Article I and Article III claims because of the
availability of alternative grounds for decision. Because
petitioner did not press his constitutional claims before
the military tribunal, and because of the particular features of petitioner’s conviction that Judges Wilkins and
Millett emphasized, this Court could resolve petitioner’s
case by using a plain-error standard of review, or relying on case-specific grounds, without addressing petitioner’s broad constitutional claims. And the multiple
alternative grounds for decision that would be available
also raise the possibility that this Court, like the court
of appeals, would fail to reach a single controlling disposition. Those aspects of petitioner’s case make it a
poor vehicle for review of his broad Article I and Article
III claims.
2. Petitioner briefly contends (Pet. 22) that this
Court should grant review to consider whether the 2006
MCA authorizes prosecutions for conduct committed
before the statute was enacted. That contention lacks
merit. The language of the 2006 MCA unambiguously
provides jurisdiction over pre-enactment conduct with
Petitioner also contends (Pet. 16) that this Court’s intervention
is necessary to overrule the USCMCR’s conclusion that conspiracy
is a violation of international law, but the government has for years
acknowledged that standalone inchoate conspiracy has not attained
international recognition at this time as an offense under customary
international law. See 5/16/12 Gov’t C.A. Br. 50. Petitioner provides
no reason to doubt that military commission judges will accept that
concession and treat the court of appeals’ decisions, rather than the
USCMCR’s, as the governing law.
6

 27
respect to the offenses it codifies. See 10 U.S.C. 950p(b)
and (d) (“Because the provisions of [the 2006 MCA]” are
declarative of existing law, they do “not preclude trial
for offenses that occurred before the date of the enactment of this subchapter.”); 10 U.S.C. 948d(a) (2006)
(providing that military commissions “shall have jurisdiction 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”). Moreover, the 2006 MCA’s specific references
to al Qaeda and to the September 11 attacks make clear
that Congress intended the military commission system
to exercise jurisdiction over conduct related to those attacks. 10 U.S.C. 948a (2006); see 152 Cong. Rec. 20,727
(2006) (statement of Rep. Hunter). In addition, petitioner’s statutory claim implicates no conflict, and its
importance is diminishing because it has no bearing on
cases that involve conduct after 2006. Further review
is unwarranted.
3. Petitioner next contends (Pet. 22-24) that this
Court should vacate his conviction based on the Ex Post
Facto Clause. The court of appeals correctly rejected
petitioner’s claim under a plain-error standard, and no
further review is warranted.
a. As the court of appeals concluded, petitioner’s ex
post facto claim is properly reviewed for plain error because petitioner failed to raise it before the military tribunal. Pet. App. 311-316. Petitioner suggests (Pet. 3132) that plain-error review should not apply because his
ex post facto claim presents a “pure question[] of law
respecting the constitutionality of a statute,” but this
Court has held that constitutional claims can be forfeited without recognizing any such exception for legal
questions. Olano, 507 U.S. at 731 (“ ‘No procedural

 28
principle is more familiar to this Court than that a constitutional right’ * * * ‘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.’ ”) (quoting Yakus v. United States, 321 U.S.
414, 444 (1944)). 7
Petitioner cannot show any violation of the Ex Post
Facto Clause, let alone a violation that amounts to plain
error. The 2006 MCA’s provision of jurisdiction over
conspiracy does not implicate the Ex Post Facto Clause
because conspiracy has been traditionally charged in
U.S. military commissions, including in the most highly
publicized military commission trials this Nation has
seen. See pp. 21-22, supra. The 2006 MCA’s codification
of that crime therefore creates no ex post facto problem.
Petitioner’s ex post facto challenge lacks merit for the
additional reason that petitioner’s conduct was illegal
under criminal statutes when petitioner engaged in the
Petitioner suggests in closing (Pet. 32), that the application of
plain-error review to a “pure question of law regarding the constitutionality of a statute” may itself be an issue warranting certiorari,
but the questions presented do not fairly encompass that issue,
Pet. i; see Wood v. Allen, 558 U.S. 290, 304 (2010). Nor is petitioner
correct (see Pet. 32) that United States v. Haddock, 956 F.2d 1534
(10th Cir.), cert. denied, 506 U.S. 828 (1992), establishes a conflict
on that point. Haddock involved a claim that an indictment was defective because it used amended statutory language to charge a defendant for acts before the statute was changed. Haddock characterized that as a type of ex post facto claim, but its conclusion that
the claim was not forfeitable was based on the fact that petitioner
was challenging the language of the indictment. Id. at 1542 (stating
that “an indictment’s failure to state an offense is a defect that may
be raised at any time”). Moreover, United States v. Marcus, 560 U.S.
258 (2010), held that such claims are in fact forfeitable, and also rejected the characterization of such contentions as ex post facto
claims. Id. at 260-261, 264.
7

 29
charged conduct. See, e.g., 18 U.S.C. 2332(b) (2000)
(criminalizing conspiracy outside the United States to
kill a U.S. national). The fact that the 2006 MCA provides a different forum for adjudication does not implicate ex post facto concerns in this case—in which petitioner admitted all relevant factual allegations and offered no defense—because any procedural differences
between the military commission system and a prosecution in an Article III court did not affect “matters of
substance.” Collins v. Youngblood, 497 U.S. 37, 45 (1990)
(citation omitted) (a “change[] in the procedures by which
a criminal case is adjudicated” only violates the Ex Post
Facto Clause if it “affects matters of substance”)
(brackets and citation omitted); see Pet. App. 331 (“The
right to be tried in a particular forum is not the sort of
right the Ex Post Facto Clause protects.”) (emphasis
omitted).
b. Petitioner’s forfeited ex post facto claim does not
warrant further review. Petitioner suggests (Pet. 22)
that whether the Ex Post Facto Clause bars military
tribunals from adjudicating conspiracy claims for pre2006 conduct is a question sufficiently important to warrant this Court’s review because of its implications for
other military tribunal cases. But the court of appeals
did not decide that question in petitioner’s case because
it applied plain-error review, and the plain-error posture would make this case a poor case for this Court’s
consideration because this Court could likewise reject
petitioner’s claim without deciding the underlying ex
post facto question. Moreover, the ex post facto challenge that petitioner asserts is one of diminishing importance because it is relevant only to individuals
charged with conspiracy offenses in military tribunals
for conduct occurring before 2006.

 30
For similar reasons, this Court’s intervention is not
warranted on the ground that questions concerning the
validity of the 2006 MCA under the Ex Post Facto
Clause have implications for the interpretation of other
enactments that state that they are “declarative of existing law” (Pet. 23) and because the government’s arguments “respecting the meaning of ‘law of war’ ” in the
UCMJ before the 2006 MCA would have ramifications
in other contexts (Pet. 23-24). The court of appeals did
not definitively decide any question regarding statutes
that are phrased as “declarative of existing law” or regarding the meaning of “law of war” under the UCMJ
because it simply held that petitioner was not entitled
to relief under the plain-error rule. Pet. App. 328-346.
And the plain-error posture makes petitioner’s claim an
unsuitable vehicle through which to give guidance on
those issues not decided by the court below, because
this Court could affirm without deciding those issues.
4. Finally, petitioner’s forfeited contention (Pet. 2429) that the 2006 MCA violates the equal protection
component of the Due Process Clause because it provides for military commission trials for alien enemy
combatants but not for enemy combatants who are U.S.
citizens also lacks merit and does not warrant further
review.
a. Because petitioner failed to raise an equal protection claim before the military commission, his claim is
reviewable only for plain error. Petitioner contends
(Pet. 29) that he preserved this claim when he complained about the government’s “discrimination based
on nationality” as one of the reasons for his boycott of
the trial. But the substance of petitioner’s complaint
was that the government exempted two British citizens

 31
from military commission prosecutions while prosecuting other foreign nationals. See Gov’t Resp. to Pet. for
Reh’g 1-2. A challenge to disparities in the treatment
of different foreign nationalities does not preserve a
claim that the 2006 MCA violates equal protection principles because it does not apply to U.S. citizens. Moreover, petitioner’s statements were an explanation for
his decision to boycott the proceedings, not a legal claim
before the tribunal. Petitioner did not request relief or
a ruling from the commission, nor did he identify any
legal ground for such relief. And petitioner made especially clear that he was not raising any legal challenge
before the tribunal when he subsequently waived all
pretrial motions.
Petitioner’s equal protection challenge falls far short
of plain error. Congress’s decision to limit military
commission jurisdiction to alien unlawful enemy combatants satisfies the deferential test that applies in this
context. See Mathews v. Diaz, 426 U.S. 67, 81 n.17
(1976) (noting that 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 exclusively
entrusted to the political branches * * * as to be largely
immune from judicial inquiry”) (citation omitted); see
also United States v. Ferreira, 275 F.3d 1020, 1025-1026
(11th Cir. 2001) (stating that congressionally enacted
distinctions between citizen and aliens “do not violate
equal protection so long as they are rationally related
to a legitimate government interest”).
Congress had a “vital national security interest in establishing a military forum in which to bring to justice

 32
foreign unlawful belligerents” who have launched terrorist attacks against the United States, and Congress
reasonably chose to do so in a way that provides for a
fundamentally fair proceeding without requiring that
such aliens be admitted into the United States. Pet.
App. 442 (Kavanaugh, J., concurring in the judgment in
part and dissenting in part) (citation omitted). Moreover, the 2006 MCA reflects the long-settled understanding that, in time of armed conflict, enemy aliens
are permissibly subject to a different legal regime than
citizens. See Harisiades v. Shaughnessy, 342 U.S. 580,
587 (1952) (stating that “[w]ar, of course, is the most
usual occasion for extensive resort to the power” to
treat aliens differently); Al-Bihani v. Obama, 590 F.3d
866, 877 n.3 (D.C. Cir. 2010) (noting that “the procedures to which Americans are entitled are likely greater
than the procedures to which non-citizens seized abroad
during the war on terror are entitled”), cert. denied,
563 U.S. 929 (2011).
Petitioner contends (Pet. 26) that some commentators have construed the Geneva Conventions to require
procedural parity for enemy aliens, but the procedural
protections under the 2006 MCA are very similar to
those available in courts-martial. Petitioner cannot claim
that any procedural differences had any effect in this
case, since he admitted the factual allegations against
him and boycotted the proceedings.
b. Petitioner’s equal protection claim does not warrant further review. Petitioner does not contend that
the court of appeals’ rejection of his claim conflicts with
any decision of another court of appeals. Although petitioner contends that his equal protection claim presents “a question of exceptional importance,” Pet. 24
(capitalization altered), none of the multiple, lengthy

 33
opinions below agreed. Four judges found the claim
“frivolous.” Pet. App. 27 n.12 (Kavanaugh, J., concurring); id. at 441-442 (Kavanaugh, J., concurring in the
judgment in part and dissenting in part); see id. at 301
(Henderson, J., dissenting); id. at 416 (Brown, J., concurring in the judgment in part and dissenting in part)
(deeming this claim “clearly meritless”). Judge Millett
dismissed the claim on plain-error grounds in a single
sentence in her concurrence, id. at 80, in an analysis
that Judge Wilkins adopted in his concurrence, id. at 96,
and the dissenters did not address petitioner’s equal
protection claim at all, see id. at 97-163. In any event,
because of the plain-error posture, petitioner’s case
would be a poor vehicle for addressing the equal protection argument that he presses.
CONCLUSION

The petition for a writ of certiorari should be denied.
Respectfully submitted.
JEFFREY B. WALL
Acting Solicitor General
DANA J. BOENTE
Acting Assistant Attorney
General
JOSEPH F. PALMER
DANIELLE S. TARIN
Attorneys

SEPTEMBER 2017