A look back at the twentieth century reveals that the most critical steps in the criminalization of mass human rights constituted the academic work of Raphel Lemkin and his conceptualization of genocide; the International Military Tribunal Charter’s criminalization of crimes against humanity and the trials that followed; and the conclusion and broad ratification of the Genocide Convention. The Convention was the first treaty since those of slavery and the “white slave traffic” to criminalize peacetime actions by a government against its citizens. Since that time, customary international law has recognized the de-coupling of crimes against humanity from wartime. The result of this process has been two separate international criminal proscrip...