One provision of the Gun Control Act of 1968 ( codified at ) criminalizes firearms purchases by , and firearms sales to , people who have renounced United States citizenship . This provision , along with similar treatment for people adjudged mentally defective or dishonorably discharged from the U.S. Armed Forces , and a restriction on mail-order firearms sales , was aimed at preventing a repeat of the circumstances which allowed Lee Harvey Oswald to obtain the rifle which he used to assassinate President Kennedy . Oswald had never actually renounced his citizenship ; he went to the U.S. embassy in Moscow one Saturday in 1959 intending to do so , but in order to delay him , Richard Edward Snyder requested that he come back on a weekday to complete the paperwork and swear the formal oath of renunciation , which Oswald never did
assassinate President Kennedy
Assassination of John F. Kennedy
Relinquishment of United States nationality