Use of Army, Navy, Marine Corps, Air Force, and Space Force as posse comitatus
Official text prohibited actmental stateif conditionpenaltylegal term
Whoever, except in cases and under circumstances expressly authorized by the Constitution or Act of Congress, uses any part of the Army, the Navy, the Marine Corps, the Air Force, or the Space Force as a posse comitatus or otherwise to execute the laws shall be or imprisoned not more than two years, or both.
History: (Added Aug. 10, 1956, ch. 1041, §18(a), 70A Stat. 626; amended Pub. L. 86–70, §17(d), June 25, 1959, 73 Stat. 144 (PDF, 2.6 MB); Pub. L. 103–322, title XXXIII, §330016(1)(L), Sept. 13, 1994, 108 Stat. 2147 (PDF, 52 MB); Pub. L. 117–81, div. A, title X, §1045(a), Dec. 27, 2021, 135 Stat. 1904.)
Simplified explanation
It is a federal crime to willfully use the Army, Navy, Marine Corps, Air Force, or Space Force to enforce laws (for example, as a posse comitatus, meaning a group called to help law enforcement). This applies unless the Constitution or an Act of Congress expressly allows it.