I would add only one thing to Jen’s thorough summary of the al-Bahlul argument next Monday, about something she references at the very end of her post:  Besides ex post facto, there is a yet another important constitutional question that the court would have to confront if it were inclined to accept the government’s “domestic common law of war” theory for affirmance.  FedCourts profs and students might want to listen up . . . .

If the court were to hold (i) that Congress, in the MCA, made it unlawful to engage in not only offenses condemned by the international laws of war (which the government concedes is not applicable here), but also offenses established by a so-called “domestic” common law of war; and (ii) that conspiracy and/or material support for terrorism are offenses under that domestic common law of war (based principally on some purported Civil War precedents); and (iii) that Congress has the constitutional power to codify such offenses, even if international law does not recognize them (a question Judge Kavanaugh, writing only for himself, answered in the affirmative in footnote 6 of his Hamdan II opinion); and (iv) that there was sufficient notice of points (i) and (ii) to overcome both statutory and constitutional ex post facto constraints . . . then those four holdings, cumulatively, would only establish that Congress can and did make it unlawful to engage in the conduct for which al-Bahlul was convicted, even if the offense occurred years before the codification.

But that would then raise another constitutional question:  Does Congress have the power to provide for trial of such offenses in military commissions, rather than in Article III courts?  After all, Article III provides that the judicial power of the United States shall be vested in courts with tenure and emolument protections; that that judicial power “shall extend to all cases, in law and equity, arising under . . . the laws of the United States”; and that “the trial of all crimes, except in cases of impeachment, shall be by jury.”  Obviously, trial of these offenses by military commission would be in tension with these textual provisions of Article III.

The Supreme Court has recognized limited exceptions to the requirement that all federal crimes be adjudicated by juries in Article III courts.  Members of the armed forces, for example, may be tried in courts-martial (a doctrine predicated on other constitutional text, in Article I, Section 8, Clause 14 and in the Fifth Amendment).  Petty offenses that were triable at common law without a jury at the time of the founding may be tried without a jury in federal courts, as can some trials for criminal contempt.  And the Court in Quirin held that, in light of early historical precedents, the Constitution does not require an Article III trial for “offenses committed by enemy belligerents against the law of war.”  See 317 U.S. 1, 40-45 (1942).  But that holding in Quirin applied only to offenses against the international law of war, since those were the only offenses on which the Court opined in that case.

The Court has never had occasion to determine whether Congress can dispense with an Article III jury trial of offenses by enemies under the so-called “domestic” law of war.  In an al-Bahlul amicus brief written in part by Just Security‘s own Steve Vladeck, the National Institute of Military Justice argues that such offenses, to the extent they are otherwise codified and constitutional, must be tried before a jury in an Article III court.  The government disagrees at pages 70-71 of its brief, relying largely on language in Quirin itself (317 U.S. at 41-42) suggesting that, in light of an 1806 statute providing for court-martial of alien spies in wartime, such spies can be tried outside of Article III . . . even though spying does not violate the international law of war.  (For what it’s worth, the Quirin Court appears to have assumed, mistakenly, that spying is a violation of the law of war.)

It’s an interesting and important constitutional question, and one to look for in the argument on Monday, at the very least as a possible ground for construing the statute narrowly pursuant to the avoidance canon.