[Jennifer Trahan is an Associate Clinical Professor at the Center for Global Affairs at New York University.]

The ICC Prosecutor announced last week that she was requesting the ICC Pre-Trial Chamber to authorize the Afghanistan Preliminary Examination moving into the Investigation stage. This would take the ICC’s Afghanistan investigation one step closer to resulting in actual cases.

We have known for quite a while that the Prosecutor was examining the situation in Afghanistan, and her past reports and press releases indicate she has been examining war crimes and crimes against humanity committed by the Taliban, Afghan government forces, and US nationals—US armed forces and CIA.

As Kevin Jon Heller notes, it will be interesting to see the US reaction to this news, yet it should hardly come as a surprise. As he also notes, the Prosecutor has been under pressure to expand her docket beyond the African continent. The US does not have anyone in the post of US War Crimes Ambassador (or head of the Office of Global Criminal Justice), so it is unclear who would lead any US response.

The US has of course one very simple way that it could react to this news, and that is to endorse the rule of law, and itself conduct any investigations into torture or ill-treatment at the hands of US nationals, be they armed forces, CIA, or contractors of either.

Under the principle of complementarity (Rome Statute art. 17), any state can avoid an ICC case proceeding by conducting a good faith investigation and/or prosecution into the same conduct. It has been high time for the US to do this, but the Prosecutor’s announcement illustrates the urgency of the US finally taking this seriously.

As a US national and a supporter of the ICC, I don’t really want to see the US locked in a showdown against the ICC. Yet, past experience (the misnamed American Servicemember Protection Act, bilateral immunity agreements, legislation allowing US forces in invade The Hague to liberate Americans in ICC custody) suggests such a confrontation is quite possible. Such an approach would not well serve either the ICC or the US, as it would amount to mere bully-tactics by the US against an institution, supported by all the US’s key allies, that is committed to ensuring rule of law for the worst crimes of concern to the international community.

Both the ICC and the US have the same interest in adhering to the rule of law, and there is a simple rule-of-law-abiding solution here: the US must undertake to do complementarity. The UK, faced with the possibility of the ICC proceeding against UK nationals for abuses committed in Iraq has been working hard to conduct complementarity; the US should do the same.

Alex Whiting raises the possibility that US conduct might not satisfy the ICC’s fairly high “gravity threshold”; yet, if the Prosecutor also includes certain “black sites” run by the CIA that were located in Rome Statute States Parties, such as Poland, Romania and Lithuania (as her announcement suggests), it is also possible that the gravity threshold will be met.  (Her announcement stated, in addition to crimes in Afghanistan, her request for authorization would include “war crimes closely linked to the situation in Afghanistan allegedly committed since 1 July 2002 on the territory of other States Parties to the Rome Statute.”)

We should not lose sight of the fact that the ICC is not aiming this investigation solely towards US nationals, and to the extent the ICC can prosecute the much more extensive crimes committed by the Taliban or other armed groups in Afghanistan, these would be welcome developments. Afghanistan has been plagued by decades of crimes, with those pertaining to US nationals constituting just one subset of what is at issue.

Meanwhile, the US should expeditiously fill the post of US War Crimes Ambassador (head of the Office of Global Criminal Justice), with the office’s initial focus being to finally conduct complementarity to ensure that justice for crimes in Afghanistan is done, and that to the extent US nationals are implicated in wrongdoing, that it is addressed within the US legal system. The US has credible and effective military and civilian investigative capacity and court systems which can and should be utilized.