This article looks at the work of the United Nations War Crimes Commission (UNWCC), and its influence on the development of international criminal law. It examines the role the UNWCC played in prosecuting war criminals, and notes the similarities between the UNWCC’s mission and the current structure and role of the International Criminal Court, particularly its focus on the principle of complementarity. The article reviews fair trial standards at the time of the national trials, and provides that many of them are present in current international human rights instruments. Still, the author submits that many trial records are still inaccessible and, as a result, there is not enough evidence to fully analyze the Commission’s efficiency in providing for a fair and impartial trial.