 Ruby was arrested immediately after shooting Oswald, and he told several witnesses that he had been distraught over President Kennedy's death and had helped the city of Dallas "redeem" itself in the eyes of the public, and that his motive for killing Oswald was "saving Mrs. Kennedy the discomfiture of coming back to trial".He also claimed he shot Oswald on the spur of the moment when the opportunity presented itself, without considering any reason for doing so.Ruby told the FBI he was "in mourning" Friday and Saturday.