The Genocide Convention states that persons charged with the crime may be prosecuted ’by such international penal tribunal as may have jurisdiction with respect to those Contracting Parties which shall have accepted its jurisdiction’. At the time no such institution existed. The International Court of Justice held that the ad hoc tribunals established by the Security Council could be deemed to be such an international penal tribunal. They undertook a large number of genocide prosecutions. The International Criminal Court, established in 2002, constitutes such an international tribunal. It has only issued a single arrest warrant for genocide, against the former president of Sudan.

International criminal justice began with efforts to prosecute Germans, including the former Emperor Wilhelm II, following the First World War. The first international trials took place at Nuremberg and Tokyo in the aftermath of the Second World War. In the early 1990s, the United Nations International law Commission submitted a draft statute for an international criminal court to the General Assembly. Subsequent work under the aegis of the Assembly culminated in the 1998 Rome Conference and adoption of the Rome Statute of the International Criminal Court. It entered into force in 2002. Meanwhile, several temporary international criminal tribunals were set up for situations in the former Yugoslavia, Rwanda, and Sierra Leone.