Title Inter-American Convention on Mutual Assistance in Criminal Matters with related optional protocol : message from the President of the United States transmitting Inter-American Convention on Mutual Assistance in Criminal Matters, adopted at the twenty-second regular session of the Organization of American States (OAS) General Assembly meeting in Nassau, the Bahamas on May 23, 1992, and the optional protocol related to the Inter-American Convention on Mutual Assistance in Criminal Matters, adopted at the twenty-third regular session of the OAS General Assembly meeting in Managua, Nicaragua, on June 11, 1993. Both instruments signed on behalf of the United States at OAS headquarters in Washington on January 10, 1995.