Introduction

Criminal law and proceedings are at the heart of state sovereignty and cooperation in criminal matters is a voluntary undertaking; a State is not obliged to cooperate with others in criminal matters unless it has agreed to do so. But over time, the parochial view that criminal law, including its effects, is local in nature has given way to an ever growing need for and actual regulation of international legal cooperation. Influential factors in this regard are increased cross-border activities, including the commission of crimes, international terrorism and the development of human rights.

International crimes are of concern to all States and therefore lend themselves to efforts at cooperation. A commitment to cooperate, in the form of extradition, is the alternative to prosecution in accordance with the aut dedere, aut judicare principle, when applicable. Cooperation is particularly important when the State is exercising jurisdiction over crimes committed abroad, but may also be necessary when a State is investigating and prosecuting crimes committed on its own territory. Prosecution of genocide, crimes against humanity, and war crimes is no exception. For example, regional cooperation has been internationally promoted in the Balkans between Serbia, Montenegro, Croatia and Bosnia and Herzegovina (the ‘Palic process’) and regional agreements are being developed.

But international law, treaty and custom, has not (yet) developed a special regime for State-to-State cooperation concerning these crimes. The Geneva Conventions and Additional Protocol I, for example, explicitly refer to cooperation in accordance with domestic legislation.