n. a system of complete control by a country's military over all activities, including civilian, in a theoretical or actual war zone, or during a period of emergency caused by a disaster such as an earthquake or flood, with the military commander having dictatorial powers. In the United States martial law must be ordered by the President as commander-in-chief and must be limited to the duration of the warfare or emergency. It cannot result in a long-term denial of constitutional rights, such as habeas corpus, the right to a trial, and to free press. Martial law was ordered in contested areas during the Civil War (but the Supreme Court ruled President Abraham Lincoln's suspension of the writ of habeas corpus was unconstitutional), and during the San Francisco earthquake and fire in 1906 when the city was in ruins, tens of thousands were homeless, and looting and disease posed great dangers to the public. Misuse of martial law, such as destruction of the veterans' encampment in Washington, D.C. under President Herbert Hoover, has proved unpopular in the United States. In many foreign countries martial law has become a method to establish and maintain dictatorships either by military leaders or politicians backed by the military. Martial law is not to be confused with "military law," which governs the conduct of the military services and applies only to service men and women.