Because 59 witnesses would have to conspire to present the same consistent account, the most ridiculous and obvious conspiracy theory of all is coming from the Lone Gunman Conspiracy Theorists.
The Copy Cat Crime: Andrew Johnson and Lyndon B. Johnson
FBI files: Evidence Suggests Lincoln's Killer Survived, Comitted Suicide. John Wilkes Booth, aged 64. In the morgue at Enid, 11 Days after death and swollen from the poison he had taken. Download The Escape and Suicide of John Wilkes Booth in PDF here.