The subject of the limits of states authorities for committing grave breaches of international humanitarian law is a subject which has a great importance especially since the last decade of 20th century and starting very armed conflicts in various countries. In this respect some countries pass laws and establish courts which have jurisdiction for try serious crimes by anyone in any where. Issuance of an international arrest warrant for incumbent foreign ministers of the Congo by a Belgian investigating magistrate motivated a dispute between Belgium and Congo and gave an opportunity to International Court of Justice (ICJ) for explaining responsibility of states authorities in committing serious crimes. In this case the ICJ first declared its jurisdiction and then delivered judgment in merits at 14 February 2002. In this judgment the Court declared that incumbent foreign affairs ministers have immunity in other states (not its national courts or certain international courts) but foreign affairs ministers will no longer enjoy this immunity after he/she ceases to hold the office of minister for foreign affairs. The courts of other states may try a former minister for foreign affairs of another states in respect of acts committed prior or subsequent to his/her period of office as well as in respect of acts committed during that period of office in a private capacity. However the Court confirms the separation between responsibility as a substantive question and immunity as a procedural question, but recognition of responsibility for foreign affairs many international jurists. ministers before courts of another states only when they have committed serious crimes in a private capacity is a problematic question in view of many international jurists.