Milligan, ex parte, case decided by the U.S. Supreme Court in 1866. By authorization of Congress, President Lincoln in 1863 suspended the writ of habeas corpus in cases where military officers held persons for offenses against the armed services. Army authorities had arrested Lambdin Milligan, a civilian who was involved in Copperhead, or pro-Confederate, activities in Indiana, and in 1864 he was tried by a military commission, convicted of fomenting rebellion, and condemned to death. The Supreme Court did not deal directly with the question of habeas corpus but with the limitation of martial law. It held that civilians might be tried by a military tribunal only where civil courts could not function because of invasion or disorder. It decided that even though the United States was at war, the federal courts of Indiana were operating, and they alone might try the case.

Merryman, ex parte, case decided in 1861 by Chief Justice Roger B. Taney sitting as a federal circuit judge in Baltimore, Md. John Merryman, a citizen of Maryland, was imprisoned by the U.S. army on suspicion of favoring the Confederacy. He obtained a writ of habeas corpus. The commanding general refused to respect this action, alleging that President Lincoln had authorized him to suspend the writ. Taney held that Article 1, Section 9, of the U.S. Constitution gave to Congress alone the power to suspend the writ in case of rebellion or invasion and that consequently the President's action had been without warrant and represented a threat to the liberties of all Americans. Lincoln, however, continued to adhere to the same practice throughout the Civil War. Congress ratified the suspension in 1863.

Stage device in Greek and Roman drama in which a god appeared in the sky by means of a crane (Greek, mechane) to resolve the plot of a play. Plays by Sophocles and particularly Euripides sometimes require the device. The term now denotes something that appears suddenly and unexpectedly and provides an artificial solution to an apparently insoluble difficulty.

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