Military police are members of an organized military force, usually uniformed, and often qualified as light infantry. The term may refer to a branch of military service, or units of that branch.
Functions within the scope of military police include both routine enforcement of military law within armed forces, but also provide classic police services related to the special relations of a military force to other civilian and opposing military groups. In the context of the former, a military police officer might apprehend and detain, for adjudication, a drunk and disorderly member of the same army. Should that prisoner be convicted through military judicial proceedings, which are not within the scope of military police, and sentenced to imprisonment, military police personnel will manage the prison.
Military police interaction with groups outside their organization include the handling of surrendered enemy personnel and of civilians in militarily restricted areas. It is not uncommon for military police to guard installations not expecting a major attack, and to provide convoy security. They operate detention facilities, although other branches are often responsible for intelligence, trials and interpretation of military law, and criminal investigation.
In the restructuring of the United States Army, military police were often a major part of a function called mobility enhancement. While that term is no longer used as a unit designation, the concept is relevant: a variety of functions help the mobility of combat troops. Combat engineers clear obstacles. Air defense artillery protects the troops from air and artillery attack while moving. Military police keep roads clear of civilians and prisoners, and perform local traffic control (i.e., as distinct from transportation movement planning).