Argument: Crimes under ICC are already prohibited by international law
"U.S. Policy Regarding the International Criminal Court". Congressional Research Service. 29 Aug. 2006 - Some ICC supporters have asserted that the crimes covered by the Rome Statute are already prohibited under international law either by treaty or under the concept of “universal jurisdiction” or both; therefore, all nations may assert jurisdiction to try persons for these crimes. The ICC, they argue, would merely be exercising the collective jurisdiction of its members, any of which could independently assert jurisdiction over the accused persons under a theory of “universal jurisdiction”; the Nuremberg trials serve as an example of such collective jurisdiction.27 ICC opponents may note that the existence of “universal jurisdiction” has been disputed by some academics, who argue that actual state practice does not provide as much support for the concept as many ICC supporters may claim.28 However, ICC supporters note, the Rome Statute does not rely entirely on universal jurisdiction; certain pre-conditions to jurisdiction must be met, including the consent of either the State on whose territory the crime occurred or the State of nationality of the accused.29 The United States is already party to most of the treaties that form the basis for the definitions of crimes in the Rome Statute, meaning U.S. citizens are already subject to the prohibitions for which the ICC will have jurisdiction.