Jonathan Witmer-Rich of the Cleveland-Marshall College of Law writes in with these comments on Hamdan II:
Reflecting on Hamdan II, I wonder if the court really responded to the government’s opening argument (in Part I.A of its opening brief). The government argued that Hamdan is triable for material support for terrorism (MST) because: (1) Congress has powers to define crimes triable by military commission pursuant to its otherArticle I war powers, apart from the Define and Punish Clause; (2) Congress did so in 10 USC § 950p(d) by using the phrase “offenses . . . otherwise triable by military commission”; and (3) MST is a pre-existing offense under what the brief calls “the US common law of war” and therefore the 2006 MCA is not a retroactive creation of a new offense. All of these points are contestable, to be sure (I, for example, am not persuaded), but I don’t think the court explained why the argument failed.
Judge Kavanaugh mentions part of the government’s argument in footnote 6, in which he alone agrees with the government on point (1) above. But Judge Kavanaugh seems to believe that this issue does not actually impact Hamdan’s case, because the scope of Congress’s powers to define offenses broader than under the international law of war would only be relevant prospectively.
The government had argued otherwise. It argued that the scope of Congress’s power—apart from the Define and Punish Clause—was critical to Hamdan’s case, because Congress in section 950v(b)(25) was merely codifying an offense that had long existed under the “US common law of war,” thus avoiding any retroactivity problem.
The court perhaps responds implicitly, as follows: on page 5, the court says “Hamdan’s conviction may be affirmed only if the relevant statute that was on the books at the time of his conduct—10 USC § 821—encompassed material support for terrorism.” The court does not, however, explain why it had to find MST in “the relevant statute” on the books during Hamdan’s conduct, as opposed to (what the government argued) in the “US common law of war.”
Why might section 821 resolve that latter argument? Maybe the analysis goes something like this: Assume arguendo that MST (in substance, if not by name) was an offense triable by military commission under the US common law of war. Then, however, Congress passed section 821, which authorized military commissions to try offenses under the “law of war”—which means the international law of war. To the extent there were any offenses (like a MST-type-offense) existing under the “US common law of war” before section 821 was passed, Congress eliminated those common law of war offenses by creating express statutory authority only for offenses under the (international) “law of war.” One might analogize to a state that enacts a comprehensive criminal code, and thereby implicitly supersedes and eliminates all common law offenses in that jurisdiction. Accordingly, when Congress enacted section 950v(b)(25), it was not codifying a pre-existing offense under the “US common law of war,” because there were no such offenses after section 821 was enacted.
There are, to be sure, many other possible reasons to reject the government’s primary argument—but the court does not articulate any. The closest it comes, as far as I can tell, is its reliance on section 821, but even then it does not explain its reasoning.