What is a drumhead court-martial?

Any summary trial is now sometimes called a drumhead court-martial. Originally the name was given only to a summary and hasty court-martial called to try an offense committed on the battlefield or during a march. Most of the forms and ceremonies are dispensed with on such occasions; in other words, it is a kind of military lynch law. The name comes from the fact that formerly such courts-martial were often conducted around a drum used as a table. A court-martial is a trial conducted under military law, which is a code of rules and regulations prescribed for the government of the Army, Navy or militia when in active service. In the United States Army there are three kinds of courts-martial, summary, special and general. The punishment power of summary and special military courts is limited by statute, while the punishment power of a general military court is usually left to the discretion of the court. A member of the armed forces of the United States is under the jurisdiction of the civil authorities in respect to civil crimes. He is subject to court-martial under the military law only when he commits a military offense.