The exercise of universal jurisdiction in cases involving crimes under international law remains highly debated and underlines a certain number of legal and political issues in its implementation. Because the principle of universal jurisdiction relies on national authorities to enforce international prohibitions, pivotal decisions are expected to reflect, to a greater or lesser extent, domestic decision-makers’ positions as to the interests of justice, the national interest and other criteria. In many States, the legal system lacks the means to investigate or prosecute on the basis of universal jurisdiction. Indeed, many legal systems do not define the term “crimes” that can be prosecuted under the principle and continue to apply domesti...