 After Kennedy was assassinated, Parr was assigned to protect Marina Oswald, and Marguerite Oswald, the widow, and the mother, respectively, of Lee Harvey Oswald until completion of Marina's testimony before the Warren Commission.Over the next 23 years, Parr conducted 15 foreign and 65 domestic protective surveys for various Presidents and Vice Presidents, and worked with security, intelligence and law enforcement professionals in all 50 states and in 37 countries.From 1969-78, he worked for the Foreign Dignitary Division as a mid-level supervisor on the Humphrey, Agnew and Ford details, and directed security for 56 foreign heads of state, including Queen Elizabeth II of Britain, Emperor Hirohito of Japan, King Juan Carlos of Spain and Pope John Paul II.