Also while in Washington, Doubleday testified against George Meade at the United States Congress Joint Committee on the Conduct of the War, criticizing him harshly over his conduct of the Battle of Gettysburg.
Mens han var i Washington, vidnede Doubleday for det fælles kongresudvalg om krigens førelse imod George Meade og kritiserede ham skarpt for hans håndtering af slaget ved Gettysburg.