The military court-martial is the oldest system of justice in the U.S., even older than the Constitution, Bill of Rights, and Declaration of Independence. The roots of military law and the court-martial extend back to ancient Rome, where it was adopted in various forms to enforce discipline within the ranks. In 1775, the Continental Congress met at the outbreak of the Revolutionary War and adopted the Articles of War, which were largely inspired by Britain’s military code. This disciplinary system was not often applied in the first World War, but in the second some two million people were court-martialed for varying offenses, resulting in some 80,000 convictions.
Among the most widely known court-martial was that of Private Eddie Slovik, a 24 year old Michigan native who abandoned his combat unit while serving in France. Following a court-martial in 1944, Slovik was shot by a firing squad, the only American service member to be executed for desertion since the Civil War.
Historically, U.S. military law been stricter and more comprehensive than civilian law — the Bill of Rights did not automatically apply to soldiers — but since World War II, courts-martial have come to mirror civilian trials in many respects. Different branches of the military used separate codes until 1950, when the U.S. Congress enacted the Uniform Code of Military Justice (UCMJ), now the basis of the military’s justice system. Under UCMJ, defendants share many of the same rights as civilians, including the right against self-incrimination and guaranteed access to counsel. However, important differences remain: jury members are chosen by the officer convening the court-martial, and many military convictions cannot be appealed to the U.S. Supreme Court, as is the case for civilian defendants. However, capital convictions can be appealed to the highest court, and military executions require the specific authorization of the President of the United States.