Edman Spangler was born in York, Pennsylvania on 10th August, 1825. While at Bland School in York he met John Wilkes Booth. During the American Civil War Spangler moved to Washington where he found work as a carpenter and scene shifter at Ford's Theatre.
On 14th April, 1865, Spangler was involved in preparing the State Box for President Abraham Lincoln. During the work a fellow employee testified that Spangler was highly critical of the president.
After the assassination of Abraham Lincoln, a member of the audience, Jacob Ritterspaugh, claimed the Spangler hit him in the face in an attempt to stop him chasing after John Wilkes Booth. Spangler also said: "Don't say which way he went." Spangler was arrested by the police and charged with being part of the plot to kill the president.
On 1st May, 1865, President Andrew Johnson ordered the formation of a nine-man military commission to try the conspirators. It was argued by Edwin M. Stanton, the Secretary of War, that the men should be tried by a military court as Lincoln had been Commander in Chief of the army. Several members of the cabinet, including Gideon Welles (Secretary of the Navy), Edward Bates (Attorney General), Orville H. Browning (Secretary of the Interior), and Henry McCulloch (Secretary of the Treasury), disapproved, preferring a civil trial. However, James Speed, the Attorney General, agreed with Stanton and therefore the defendants did not enjoy the advantages of a jury trial.
The trial began on 10th May, 1865. The military commission included leading generals such as David Hunter, Lewis Wallace, Thomas Harris and Alvin Howe and Joseph Holt was the government's chief prosecutor. Mary Surratt, Lewis Powell, George Atzerodt, David Herold, Samuel Mudd, Michael O'Laughlin, Edman Spangler and Samuel Arnold were all charged with conspiring to murder Lincoln. During the trial Holt attempted to persuade the military commission that Jefferson Davis and the Confederate government had been involved in conspiracy.
Joseph Holt attempted to obscure the fact that there were two plots: the first to kidnap and the second to assassinate. It was important for the prosecution not to reveal the existence of a diary taken from the body of John Wilkes Booth. The diary made it clear that the assassination plan dated from 14th April. The defence surprisingly did not call for Booth's diary to be produced in court.
On 29th June, 1865, Spangler was found guilty of being involved in the conspiracy to murder Abraham Lincoln and was sentenced to six years in prison. Mary Surratt, Lewis Powell, George Atzerodt and David Herold were also found guilty of the crime and hanged at Washington Penitentiary on 7th July, 1865.
After his release from prison Spangler was given 5 acres of land to farm by Samuel Mudd. Edman Spangler also did carpentry work before his death on 7th February, 1875.