I’ve been lurking on the sidelines, greatly enjoying this symposium and wondering what I could add that hasn’t already been discussed. A few things occur to me, but I thought I might start by venturing an answer to the question Brian posed yesterday: “even if there was an actual war (which is debatable), does serving as a driver/bodyguard constitute an internationally recognized war crime (i.e. did he violate the laws of war)? “ At least in Hamdan’s case, it clearly does not, for reasons that Gabor Rona of Human Rights First has explained far better than I ever could:

As for civilians who take up arms, participation in hostilities absent a privilege to do so is not, in itself, a violation of the laws of war (war crime). It is merely a disqualifier for PoW status. A civilian who attacks an enemy combatant may be violating domestic criminal law (assault, murder, etc.) but does not thereby violate  IHL. It is absolutely true that civilians who take part in hostilities are not protected in the sense of being immune from targeting. Indeed, they may be targeted so long as they are taking direct part in hostilities. They do not, however, forfeit civilian status, although their mere participation in hostilities might be a crime under domestic law, or if, for example, they are targeting civilians, which is a war crime.

Under International Humanitarian Law (IHL), in other words, an unprivileged belligerent can only be prosecuted for a war crime if his act would have been illegal even for a privileged belligerent – killing a civilian, for example. He cannot be prosecuted for a “war crime” whose underlying act would not have been a war crime if committed by a privileged combatant, such as attacking an enemy soldier. A privileged combatant would not violate the laws of war by helping transport weaponry to attack US forces in Afghanistan; Hamdan thus did not commit a war crime by driving the car that carried the surface-to-air missiles.

This does not mean, of course, that Hamdan cannot be prosecuted for serving as bin Laden’s driver. What it means is that he can only be prosecuted for his actions in a domestic court for domestic crimes. If the surface-to-air missiles he helped transport were used to kill US soldiers, for example, Hamdan could potentially be guilty of aiding-and-abetting murder.

Unfortunately, the nuances of privileged and unprivileged belligerency are lost on the Bush Administration. Hence the prosecution’s insistence in Hamdan’s case that any attempt by an “unlawful enemy combatant” to kill a soldier is a war crime. That claim is simply incorrect, for all the reasons just mentioned – and as Judge Allred recognized when he refused to give the prosecution’s requested instruction to the jury.

But that isn’t even the worst of it. One often hears – particularly in the US, with its Alice-in-Wonderland approach to IHL – that a civilian commits a war crime simply by participating in hostilities. Indeed, I fear (and hope that he will correct me if I’m wrong) that Jason Ralph argued precisely that on Monday when he wrote, “civilians cannot abuse their privileged position by suddenly deciding to become combatants. Should they decide to do this, then they can be charged with ‘unlawful combatancy’.” That position is mistaken: although “unprivileged combatancy” can lead to the commission of war crimes – namely, when the civilian who is directly participating in the hostilities commits an act that a privileged belligerent could not commit – “unprivileged combatancy” is not itself a war crime. Differently put, there is no “status” war crime of unprivileged combatancy.

Once again, however, things are different at the domestic level. As Dapo Akande (Oxford) has pointed out, states can, if they so choose, create a domestic “status” crime of unprivileged combatancy:

Now, if a State were to make it an offence for a person to fight without fulfilling the conditions for lawful combatancy international law does not prohibit that. However, that would not be a violation of the laws and customs of war. It is a domestic crime but one that international law allows prosecution of.

No such crime exists in US domestic law, of course, which is why the military commissions have been given jurisdiction over non-existent war crimes like “murder in violation of the law of war,” “conspiracy,” and “material support for terrorism.” We can only hope that all of the military commissions are presided over by Judge Allreds – alas, prosecutors have indicated that they intend to pursue their mistaken legal theories in at least 80 other cases.

Kevin Jon Heller is Senior Lecturer at the University of Auckland Faculty of Law in New Zealand, writes at Opinio Juris, and is the author of the forthcoming book The Nuremberg Military Tribunals and the Origins of International Criminal Law (Oxford University Press, 2010).