John F. Parker. was one of the first members of Washington's Metropolitan Police Force, and was assigned to be President Abraham Lincoln's bodyguard on the night he was assassinated. Parker was born on May 19th, 1830 in Virginia. The Metropolitan Police force was first started in 1861 and he was one of the original 150 officers.
Parker did not have the best record as a police officer; he had appeared in front of the board for various misconduct charges such as visiting a prostitute, being drunk on duty, sleeping on duty, and firing a pistol through someone's window. For some unknown reason, he still was made into one of the Presidental guards on November 4, 1864.
On April 14, 1865, John Parker was supposed to report at the White House at 4 P.M. to escort Lincoln and his wife to the theatre. He showed up 3 hours late and went to Ford's Theatre to wait for them to arrive. When they showed up, Parker was stationed to sit right outside the stairs to the Presidential Box which was roughly 6 feet above the stage.
Fords theatre is located on 7th Street, a place close to many saloons and other party places where officers would often go for a good time. Parker soon disappeared from his post and having been given the perfect opportunity, John Wilkes Booth squeezed right past.
On May 1st Parker was charged with neglect of duty for failing to protect the President. He was tried on May 3rd and the charge was dismissed on June 2nd. There isn't a transcript of the hearing that exists, and the papers didn't even mention anything. Parker actually kept his job as a police officer until 1868 when he was fired for sleeping when he was supposed to be on duty.
Source:
http://members.aol.com/RVSNorton1/Lincoln61.html