In Washington's Old Penitentiary, final arguments are being made in the Lincoln conspiracy trial
The nine officers of the Commission to try the accused Lincoln murder plotters had been named on May 6, 1865. Preliminaries and the taking of testimony had occupied the following five weeks at the Old Penitentiary in the grounds of the Washington Arsenal and had concluded on June 14, 1865. Final arguments continued for another two weeks, deliberation began June 29, 1865, and the sentences were pronounced on July 6, 1865. (By John Osborne)
Clara E. Laughlin, The Death of Lincoln: The Story of Booth's Plot, His Deed and the Penalty (New York: Doubleday, Page and Company, 1909), 190.