The Adequacy of Applying the Principle of Complementary Jurisdiction for the Crime of Aggression

The principle of complementarity is one of the essential elements for the establishment and the functioning of the International Criminal Court, which importantly contributes to the objective of preventing impunity for international crimes, while taking into account the principle of sovereignty of states. This principle reiterates the rights and the obligations of firstly states to investigate, prosecute and bring perpetrators of criminal acts to justice, given that the International Criminal Court was established as a body which exercises its jurisdiction only when otherwise competent states are unable or unwilling to criminally prosecute individuals. While states have discussed the exercise of the International Criminal Court’s jurisdiction over this crime at the Review Conference in Kampala in 2010, alongside accepting and including its definition in the Rome Statute, they did not modify the principle of complementarity neither in the new provisions nor as stipulated in the existing ones that govern this principle. As the International Criminal Court can exercise jurisdiction over the crime of aggression since 17 July 2018, this article discusses the adequacy of applying the principle of complementary also for the crime of aggression, notably in light of its inextricable link with the act of aggression, committed by a state, as well as with possible issues that states and the whole international community may need to confront in the future when exercising such jurisdiction in practice.

Keywords: International Criminal Court, Rome Statute, jurisdiction, principle of complementarity, aggression.