In 1863, in the midst of the Civil War, Congress passed a statute authorizing President Lincoln to suspend the writ of habeas corpus, conditioned on certain limitations. President Lincoln did so in September of that same year. The statute mandated that the Secretaries of State and War must give to the circuit and district court judges a list of the names of U.S. citizens held as prisoners (other than prisoners of war). If a grand jury did not return an indictment against a particular prisoner, that prisoner was to be brought before a judge for a decision of discharge or further action. Lambdin P. Milligan (defendant), an Indiana resident without a military background, was arrested in October 1864 by order of the commander of the military district of Indiana and imprisoned. Milligan was brought before a military tribunal, found guilty of various charges of conspiracy against the government, and sentenced to be hanged. On January 2, 1865, the United States Circuit Court for Indiana empaneled a grand jury, which did not return an indictment against Milligan. Milligan then petitioned the court for release, citing the 1863 statute and arguing that the military tribunal had no jurisdiction to try him.