Martial law is a system of absolute miltary control over all military and civilian activities of a country, in a theoretical or actual war zone, during civil disorder, in occupied territory, after a coup d'etat, or during a state of emergency caused by a natural disaster such as an earthquake or flood. In the United States only the President as commander-in-chief has authority to impose martial law and it must be limited to the duration of the warfare or emergency. It cannot be imposed in a manner resulting in a long-term denial of constitutional rights.
Martial law seeks to maintain public order in times of a crisis, when the normal institutions of justice either cannot function or could be deemed too slow or to ill-equipped for the new situation. Usually martial law reduces some of the personal rights ordinarily granted to the citizen, limits the length of the trial processes, and prescribes more severe penalties than ordinary law.
