 Joseph Holt was Judge Advocate General of the United States Army from 1862 to 1875.He presided over the trials of the Lincoln assassination conspirators.During the trials, accused conspirators Dr. Samuel Mudd (who treated John Wilkes Booth's broken leg) and Mary Surratt (at whose downtown boarding house the conspirators met) were held at the Old Capitol Prison opposite the U.S. Capitol (the modern day United States Supreme Court Building stands on the site today).