Extension of military rule to civilian populations during times of war and other emergencies.

Under martial law, military officials have the authority to take actions that suspend some or all civil liberties and would normally be unconstitutional. The justification for martial law lies in the fundamental concept of self-defense. When survival is threatened, people’s first obligation must be to self-preservation and not to the Constitution. Although no specific provision in the Constitution authorizes martial law, the Supreme Court has found that the concept is an implicit part of the constitutional order. Some evidence for this position comes from Article I, section 7, which provides for the suspension of the writ of habeas corpusHabeas corpus[Habeas corpus] in certain limited circumstances. In part because martial law is not plainly set forth in the Constitution, there is much uncertainty about what the term means, about what actions may be taken during martial law, and about whether such actions are entrusted to Congress or the president.Military and the Court

The Court has considered the constitutionality of martial law on a few occasions. During the Civil WarCivil War (1861-1865), President Abraham Lincoln suspended the writ of habeas corpus and ordered the military to arrest and try civilians. Chief Justice Roger Brooke Taney, sitting as a circuit judge in Baltimore, Maryland, was subsequently presented with a claim by John Merryman that he was being held illegally by Lincoln’s army. In Ex parte Merryman[case]Merryman, Ex parte[Merryman, Ex parte] (1861), Taney concluded that Lincoln’s suspension of the writ was illegal. Lincoln never formally responded to the charge, but he continued to issue orders suspending the writ. In Ex parte Vallandigham[case]Vallandigham, Ex parte[Vallandigham, Ex parte] (1864), though, the Supreme Court effectively upheld the military’s decision to arrest and try Clement Vallandigham, who then applied to the Court for a writ of habeas corpus. The Court concluded that it did not have the authority to issue the writ to military authorities, thus leaving undisturbed the system of martial law Lincoln had imposed.

After the end of the Civil War, the Court was presented with another opportunity to consider the constitutionality of martial law. In Ex parte Milligan[case]Milligan, Ex parte[Milligan, Ex parte] (1866), the Court found that the President Lincoln violated the Constitution when he decided to suspend the writ of habeas corpus in the state of Indiana. Writing for the Court, Justice David Davis concluded that the Constitution is a law “for rulers…equally in war and in peace, and covers with the shield of its protection all classes of men, at all times, and under all circumstances.” Nevertheless, Davis concluded that the Constitution permitted martial law when war prevailed and closure of the civilian courts made it impossible to administer justice.

The Court also considered the constitutionality of martial law during World War II. In 1941, immediately after the attack on Pearl Harbor, the governor of Hawaii declared martial law, an action ratified by President Franklin D. Roosevelt two days later. In Duncan v. Kahanamoku[case]Duncan v. Kahanamoku[Duncan v. Kahanamoku] (1946), the Court considered a challenge to that order by two civilians who had been convicted by military courts even though the civilian courts were open. In his opinion for the Court, Justice Hugo L. Black wrote that “our system of government clearly is the antithesis of total military rule.” Citing Milligan, Black concluded that the convictions should be overturned because the conditions specified in Milligan had not been satisfied. Duncan, like Milligan, speaks both of the permissibility of martial law and of the limits upon it. In both cases, however, the Court issued opinions only after hostilities were over.

• Corwin, Edward S. Total War and the Constitution. New York: Alfred A. Knopf, 1947.
• Fairman, Charles. The Law of Martial Rule. 2d ed. Chicago: University of Chicago Press, 1940.
• Neeley, Mark E. The Fate of Liberty: Abraham Lincoln and Civil Liberties. New York: Oxford University Press, 1991.
• Rankin, Robert. When Civil Law Fails. Durham, N.C.: Duke University Press, 1939.
• Rossiter, Clinton. Constitutional Dictatorship. Princeton, N.J.: Princeton University Press, 1948.

Civil War

Duncan v. Kahanamoku

Habeas corpus

McCardle, Ex parte

Military and the Court

Milligan, Ex parte

Presidential powers

War and civil liberties

War powers