 Booth had free access to all parts of Ford's Theatre as a famous and popular actor who had frequently performed there and who was well known to its owner John T. Ford, even having his mail sent there.Many believe that Booth had bored a spyhole into the door of the presidential box earlier that day, so that he could observe the box's occupants and verify that the President had made it to the play.Conversely, an April 1962 letter from Frank Ford, son of the theatre manager Harry Clay Ford, to George Olszewski, a National Park Service historian, includes