During the trial of Mary
Surratt, accused of aiding John Wilkes Booth, many believed she was innocent
even after a military tribunal convicted her. On the day set for her execution,
Brig. General Winfield S. Hancock had reason to believe that President Andrew
Johnson might issue a reprieve. Hancock therefore established relays of horses,
whose riders were to race to the grounds of the Washington Arsenal if the
hanging was deferred.
