Murder of United States Nationals Act of 1991

Murder of United States Nationals Act of 1991 - Amends the Federal criminal code to provide for the prosecution of individuals who murder U.S. nationals abroad. Bars such a prosecution: (1) if prosecution has been previously undertaken by a foreign country for the same act or omission; and (2) unless the Attorney General determines that the act or omission took place in a country in which the person is no longer present and the country lacks the ability to lawfully secure the person's return. Specifies that the Attorney General's determination is not subject to judicial review.

Authorizes the Attorney General, in the course of enforcement of this Act, to request assistance from any Federal, State, local, or foreign agency.

Permits, in the exercise of comity, the surrender of persons who have committed crimes of violence against U.S. nationals in foreign countries without regard to the existence of any extradition treaty with such foreign government if the Attorney General certifies that: (1) evidence has been presented by such foreign government which indicates that had the offenses been committed in the United States they would constitute crimes of violence; and (2) the offenses charged are not of a political nature.