UCMJ

The Uniform Code of Military Justice (UCMJ, 64 Stat. 109, 10 U.S.C. §§ 801–946), is the foundation of military law in the United States. It was established by the United States Congress in accordance with the authority given by the United States Constitution in Article I, Section 8, which provides that "The Congress shall have Power....To make Rules for the Government and Regulation of the land and naval forces."

On 30 June 1775, the Second Continental Congress established 69 Articles of War to govern the conduct of the Continental Army.

Effective upon its ratification in 1788, Article I, Section 8 of the United States Constitution provided that Congress has the power to regulate the land and naval forces. On 10 April 1806, the United States Congress enacted 101 Articles of War, which were not significantly revised until over a century later. Discipline in the sea services was provided under the Articles for the Government of the United States Navy (commonly referred to as Rocks and Shoals). While the Articles of War evolved during the first half of the twentieth century, being amended in 1916, 1920, and culminating with the substantial reforms in the 1948 version pursuant to the Selective Service Act of 1948 (a/k/a the Elston Act) (Pub.L. 80-759, 62 Stat. 604), its naval counterpart remained little changed by comparison. The military justice system continued to operate under the Articles of War and Articles for the Government of the Navy until 31 May 1951, when the Uniform Code of Military Justice went into effect.

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