In fact, there were nearly 1,000 military tribunals in which Confederates, both regulars and guerrillas, were charged with various violations of the laws of war – mostly related to the treatment of prisoners of war. Some of these trials even led to acquittals. For example, the camp commander at Salisbury Prison, Major John Gee, was arrested in the fall of 1865 and charged with similar crimes as Wirz. Unlike Wirz, Gee was unanimously acquitted in the spring of 1866. After the war, General Grant actually prevented the tribunal of another of Salisbury's commanders, Bradley T. Johnson, who faced charges of negligence at the prison and for burning Chambersburg, Pennsylvania in the summer of 1864. Even among those convicted, Wirz did not stand alone for the atrocities of Andersonville. James Duncan, who worked in the quartermaster's office at Andersonville, was arrested and convicted of manslaughter by a military tribunal for his role in intentionally withholding rations from prisoners. He was sentenced to hard labor at Fort Pulaski, where he escaped a year later.
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Perhaps the most enduring claim about Henry Wirz is that he was the only person executed by the Federal government in connection with the Civil War. But this was not the case. For example, more than three hundred Sioux Indians were convicted and sentenced to death by military tribunal in 1862. President Lincoln commuted the sentence of most, but in December 1862 thirty eight were hanged by military tribunal in what remains the largest mass execution in American history. Although his execution is the most famous of the Civil War, Wirz was certainly not the only Confederate to be executed. Perhaps most prominent of these other Confederates to be executed was Champ Ferguson, who was convicted in the fall of 1865 for the execution of at least 53 captured Union soldiers, although Ferguson claimed the total was higher. In another high-profile case, Confederate officer Robert Kennedy was executed by a military tribunal for planting explosives around New York City, including heavily trafficked locations like P.T. Barnum's Museum.