Gustave Gilbert served as prison psychologist of World War II German prisoners and participated in the Nuremberg trials attesting to the sanity of Rudolf Hess.
In 1945, after the end of the war, Gilbert was sent to Nuremberg, Germany, as a translator for the International Military Tribunal for the trials of the World War II German prisoners. Gilbert was appointed the prison psychologist of the German prisoners. Gilbert also participated in the Nuremberg trials as the American Military Chief Psychologist and provided testimony attesting to the sanity of Rudolf Hess. 
