The implementation of the provisions of treaties and conventions is a duty arising from conventional and customary international law. In the case of the Rome Statute this duty is implied, since only by fulfilling it will states be able properly to comply with the obligation of complementarity. Moreover, the entire Statute is based on the assumption that states parties will in most cases be able and willing to investigate and prosecute crimes. Implementing the Rome Statute in Latin America is complicated by gaps existing in domestic legislation and the special characteristics of the legislation of civil law states.