Q: As a scholar of comparative constitutional law what is your opinion of the doctrine of complementarity? How does complementarity actually work to accommodate both national sovereignty and the enforcement of fundamental human rights? Under what circumstances can we expect the Chief Prosecutor to accept assertions of national jurisdiction?

A: From the perspective of comparative constitutional law the doctrine of complementarity is a good thing. It reassures those jurisdiction that are afraid of international overreaching that they will have a degree of autonomy, and also allows those jurisdictions with more capacity for justice to pursue issues of impunity in their own way.

From the perspective of the international system, however, I think complementarity raises some problems and that it is clearly a second best solution. The problems are those that are familiar in debates over universal jurisdiction. The system of universal jurisdiction means that international crimes are adjudicated, potentially, in the courts of a hundred and ninety some separate countries. This could have grave consequences for consistency and development of the law. The complementarity regime is a half-best solution from the point of view of the international system.

It was designed to induce powerful states like the US to join the Rome Statute, but, of course, it ultimately failed to do that. In the negotiations the US was obviously pushing for the doctrine of complementarity, but there were some in the US that would not have supported the Statute unless it included blanket immunity for the US. So even though the US lobbied for complementarity, fixing or reforming the regime of complementarity is unlikely to induce the US to join the Rome Statute.

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