How the complementarity principle has affected the jurisdiction of ICC and the admissibility of cases brought before the court?

The complementarity principle underpins the International Criminal Court's (ICC) jurisdiction by asserting that the Court can only prosecute cases when national legal systems are unwilling or unable to do so genuinely. This principle ensures that the ICC acts as a last resort, promoting accountability at the national level first. Consequently, cases brought before the ICC must demonstrate that national proceedings are either ineffective or non-existent, influencing the admissibility of cases and requiring a careful assessment of state actions before the ICC can intervene. This framework aims to reinforce national sovereignty while ensuring justice for serious international crimes.