Martial Law

Martial law is the imposition of military rule by military authorities over designated regions on an emergency basis. Martial law is usually imposed on a temporary basis when the civilian government or civilian authorities fail to function effectively (e.g., maintain order and security, or provide essential services), when there are extensive riots and protests, or when the disobedience of the law becomes widespread. In most of the cases, military forces are deployed to subdue the crowds, to secure government buildings and key or sensitive locations, and to maintain order. http://en.wikipedia.org/wiki/Martial_law

What if you're in Pure War?