Hamdan 2, USA 0

FILE - This undated file photo, provided by Professor Neal Katyal, shows Salim Hamdan. A federal appeals court on Tuesday thr
FILE - This undated file photo, provided by Professor Neal Katyal, shows Salim Hamdan. A federal appeals court on Tuesday threw out the conviction of Hamdan, a former driver for Osama bin Laden who served a prison term for material support for terrorism. (AP Photo/Photo courtesy of Prof. Neal Katyal, File) ** NO SALES **

The United States Court of Appeal for the District of Columbia Circuit released its decision Tuesday in the case of Hamdan v. United States, overturning Hamdan's conviction by the Guantanamo military commission on charges of providing material support for terrorism.

Hamdan attracted attention in U.S. media as the driver of Osama bin Laden, and in legal circles for setting the precedent in Hamdan v. Rumsfeld in which the U.S. Supreme Court found that the tribunals set up by the Bush administration to try Guanatanamo detainees were illegal under U.S. military law and the Geneva Conventions. As a result of that decision a new Military Commissions Act (2006) was established in an attempt to get legal convictions.

Now the D.C. Circuit Court has thrown out one of the first of those convictions, once again setting an important Hamdan precedent. But what does the decision mean?

Although detained as a combatant in 2001, Hamdan was ultimately charged with conspiracy and with five counts of providing material support to al Qaeda for acts committed between 1996 and 2001. In August 2008 he was acquitted of conspiracy but convicted of providing material support, and given a 66-month sentence. He was released in early 2009 to Yemen, having been given credit for serving most of his sentence before trial.

The Circuit Court began by rejecting the government position that the case was moot because Hamdan had already been released, giving it one terse paragraph:

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.

As a well-worn proposition this is not important as a legal development, but it is important because of what it says about the government's case: they were willing to argue even a well established proposition on criminal appeals to avoid losing their conviction.

The Court went on to consider the 2006 Act under which the conviction had been made. That Act set out a large list of terrorism-related crimes for which prosecutions could be brought, including providing material support. But the Court found that it could not create retroactive crimes, and therefore could not authorize prosecution of any crime listed that was not a crime when the alleged acts were committed. The prohibition on retroactive laws is a base proposition of the rule of law called the "ex post facto clause" issue in the U.S.

Of course, U.S. laws on military commissions did exist in 2001 and permitted prosecutions and convictions for violations of the 'laws of war'. The laws of war, in turn, were defined by reference to the international laws of war.

While numerous laws of war, including laws against terrorist acts, were well-recognized long before 2001, a prohibition on "providing material support" was not and is not an internationally recognized law of war. The Court concluded that the Commission could not convict Hamdan of the 'crime' of providing material support to terror because it simply was not a crime prior to 2006 and certainly not when the acts were committed.

Accordingly, the decision will allow commission prosecution of crimes recognized as international war crimes at the time they are committed, but will not permit the White House to re-write the laws of war after the fact to encompass all those captured in the war on terror. Acts constituting material support for terror committed after 2006 are still subject to the 2006 Act for those unfortunate enough to be captured as 'enemy combatants' by the U.S.

The Court suspended implementation of the Order for seven days to permit an appeal, but it seems unlikely the Supreme Court will intervene to grant the executive retroactive criminal powers. While the question of the detention centre at Guantanamo Bay and the Military Commission set up to try its inmates is not a live issue in the current presidential election, it is certain that whoever wins will find this brief -- and nearly two hundred inmates -- still waiting for them in January 2013.

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