Military Law is primarily a tool for ensuring order and discipline within the armed forces. As such, Military Law provides for punishment of military personnel who act in violation of military statutes.

Court-martial proceedings and punitive discharge involve discipline and punishments authorized by the Uniform Code of Military Justice (UCMJ) for minor to serious offenses and chronic offenders.

The summary court-martial is a non-judicial proceeding reserved for relatively minor offenses. The other two types of courts-martial, the special court-martial and the general court-martial, are judicial proceedings that may lead to felony criminal convictions and result in incarceration and/or punitive discharge from the armed forces.

Military justice refers to the Criminal Law component of Military Law. It is a body of law codified in the UCMJ and implemented through the Manual for Courts-Martial.

The military justice system applies to all active-duty military personnel, as well as to military reservists while they are on active duty, and certain civilian Department of Defense employees during wartime.