These are known as the Tokyo Trials, the Tokyo War Crimes Tribunal or simply as the Tribunal, was convened on April 29, 1946, to try the leaders of the Empire of Japan for three types of crimes:"Class A" crimes were reserved for those who participated in a joint conspiracy to start and wage war, and were brought against those in the highest decision-making bodies; "Class B" crimes were reserved for those who committed "conventional" atrocities or crimes against humanity; "Class C" crimes were reserved for those in "the planning, ordering, authorization, or failure to prevent such transgressions at higher levels in the command structure. "