Ex Parte Milligan - The Court's Decision

The Court's Decision

The Supreme Court decided that the suspension of habeas corpus was lawful, but military tribunals did not apply to citizens in states that had upheld the authority of the Constitution and where civilian courts were still operating. In essence, the Court ruled that military tribunals could not try civilians in areas where civil courts were open, even when the military had been authorized to detain individuals without trial.

It observed further that during the suspension of the writ of habeas corpus, citizens may be only held without charges, not tried, and certainly not executed by military tribunals; the writ of habeas corpus is not the right itself but merely the ability to issue orders demanding the right's enforcement.

It is important to note the political environment of the decision. Post-Civil War, under a Republican Congress, the Court was reluctant to hand down any decision that questioned the legitimacy of military courts, especially in the occupied South. The President's ability to suspend habeas corpus independently of Congress, a central issue, was not addressed, probably because it was moot with respect to the case at hand. Though President Lincoln suspended the writ nationwide on September 24, 1862, Congress ratified this action almost six months later, on March 3, 1863, with the Habeas Corpus Suspension Act. Milligan was detained in 1864, well after Congress formally suspended the writ. That notwithstanding, military jurisdiction had been limited.