D.C. Circuit Opinion in Hamdan

First, despite Hamdan’s release from custody, this case is not moot. This is a direct appeal of a conviction. The Supreme Court has long held that a defendant’s direct appeal of a conviction is not mooted by the defendant’s release from custody. Second, consistent with Congress’s stated intent and so as to avoid a serious Ex Post Facto Clause issue, we interpret the Military Commissions Act of 2006 not to authorize retroactive prosecution of crimes that were not prohibited as war crimes triable by military commission under U.S. law at the time the conduct occurred. Therefore, Hamdan’s conviction may be affirmed only if the relevant statute that was on the books at the time of his conduct – 10 U.S.C. § 821 – encompassed material support for terrorism. Third, when Hamdan committed the relevant conduct from 1996 to 2001, Section 821 of Title 10 provided that military commissions may try violations of the “law of war.” The “law of war” cross-referenced in that statute is the international law of war. See Quirin, 317 U.S. at 27-30, 35-36. When Hamdan committed the conduct in question, the international law of war proscribed a variety of war crimes, including forms of terrorism. At that time, however, the international law of war did not proscribe material support for terrorism as a war crime. Indeed, the Executive Branch acknowledges that the international law of war did not – and still does not – identify material support for terrorism as a war crime. Therefore, the relevant statute at the time of Hamdan’s conduct – 10 U.S.C. § 821 – did not proscribe material support for terrorism as a war crime. Because we read the Military Commissions Act not to retroactively punish new crimes, and because material support for terrorism was not a pre-existing war crime under 10 U.S.C. § 821, Hamdan’s conviction for material support for terrorism cannot stand. We reverse the judgment of the Court of Military Commission Review and direct that Hamdan’s conviction for material support for terrorism be vacated.

It is ORDERED, on the court's own motion, that the Clerk withhold issuance of the mandate herein until seven days after disposition of any timely petition for rehearing or petition for rehearing en banc. See Fed. R. App. P. 41(b); D.C. Cir. Rule 41. This instruction to the Clerk is without prejudice to the right of any party to move for expedited issuance of the mandate for good cause shown.