A few weeks before the hanging and after the war had ended, Milligan’s attorney filed for a writ of habeas corpus at a federal court claiming that Milligan should not have been denied his right to a trial by a jury. The lawyer argued that the military courts were unconstitutional and that the president could not suspend the writ of habeas corpus. The Supreme Court agreed in a 9-0 decision and released him from custody.
The Supreme Court ruled 9-0 in favor of Milligan in all three issues raised during the case. Should Milligan be released from custody?
Yes, he should be released from custody.
Was it constitutional for the military tribunal to arrest and charge Milligan?
The military tribunal arrest and conviction was unconstitutional.
Should Milligan be granted the right for a writ of habeas corpus?
Yes he should be granted the right for a writ of habeas corpus.
The majority opinion stated that so long as civil courts were active at home, it was unconstitutional to try American citizens by military tribunal.
http://sites.gsu.edu/us-constipedia/ex-parte-milligan-1866/
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