Samuel T. Morison has posted History and Tradition in American Military Justice on SSRN, at at.  It is forthcoming this fall in the Univ. of Penn. Journal of Int’l Law.  Here’s the abstract:

At present, there are two military commission cases involving terrorism defendants incarcerated at Guantánamo Bay making their way through the appellate courts. In both cases, the defendants are challenging their convictions for “providing material support for terrorism.” While this is a federal offense that could be prosecuted in an Article III court, the legal issue in these appeals is whether providing material support is also a war crime subject to the jurisdiction of a military tribunal. Congress incorporated the offense into the Military Commissions Act, but that is not dispositive, since it is arguably beyond Congress’ legislative competence to create war crimes out of whole cloth and then impose them on foreign nationals having no jurisdictional nexus to the United States.

As a result, the Government has not disputed that there must be at least some historical evidence that the conduct now styled “providing material support” to an enemy previously has been treated as a war crime, where the defendant was a non-resident alien who owed no duty of allegiance to the injured State. In what might be fairly described as a desperate attempt to discharge its burden of persuasion, the Government has now embraced the only “precedent” that comes close to fitting this description. This is problematic, however, because it is also one of the most notorious episodes in the history of American military justice.

In 1818, then Major General Andrew Jackson led an armed invasion of Spanish Florida, thereby instigating the First Seminole War. In the course of the conflict, his troops captured two British citizens who had been living in Florida among the Seminole Indians. In his inimitable style, Jackson impetuously ordered the summary trial and execution of these men, allegedly for “inciting” the Seminoles to engage in “savage warfare” against the United States. Worse yet, Jackson’s immediate motivation for the invasion was to recapture fugitive slaves, who had escaped from the adjacent States and found refuge among the Seminoles. In addition to territorial expansion, his mission was to return this “property” to their “rightful” owners and prevent Florida from serving as a safe haven for runaway slaves.

Remarkably, the legal basis of the Government’s assertion of military jurisdiction over material support charges therefore rests on Jackson’s decision to execute two men, who were almost certainly innocent, in the context of a war of aggression waged to vindicate the property rights of antebellum Southern slaveholders. The purpose of this essay is to reintroduce the episode to a wider audience, and to reflect on the implications of the Government’s decision to rely on it as a precedent for a modern war crimes prosecution.