Synergy of the International Criminal Court and Regional Mechanisms to Combat the Impunity

International criminal justice is one of the fundamental goals of international community that considered as the subject of deferent actions in national, regional and international levels. Although regional mechanisms were delayed to combat the impunity compared to international and national courts and this process is very slow in Asia and America. In fact, regional judicial implementation of international norms is relatively common in the fields of international human rights and there are attempts to create a regional international criminal court, such as the proposed addition of the criminal jurisdiction to the African Court of Justice and Human Rights. But the importance and the necessity of these courts and their relationship to ICC are the new legal challenge. Generally, the case is admissible before the ICC if the State which has jurisdiction is unwilling or unable genuinely to carry out the investigation or prosecution. However, the important issue is: how do regional tribunals fit with the principle of complementarity in Rome Statute? The answer to this question requires the proper understanding of the legal relationship between states and regional tribunals and the contextualized application of the principles of treaty interpretation enshrined in the Vienna Convention.