The Posse Comitatus Act does not apply where Congress has expressly authorized use of the military to execute the law. Congress has done so in three ways, by giving a branch of the armed forces civilian law enforcement authority, by establishing general rules for certain types of assistance, and by addressing individual cases and circumstances with more narrowly crafted legislation. Thus it has vested the Coast Guard, a branch of the armed forces, with broad law enforcement responsibilities. Second, over the years it has passed a fairly extensive array of particularized statutes, like those permitting the President to call out the armed forces in times of insurrection and domestic violence, 10 U.S.C. §§ 331-335. Finally, it has enacted general legislation authorizing the armed forces to share information and equipment with civilian law enforcement agencies, 10 U.S.C. §§ 371-382.
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The Posse Comitatus Act proscribes use of the Army or the Air Force to execute the law. It says nothing about the Navy, the Marine Corps, the Coast Guard, or the National Guard. The courts have generally held that the Posse Comitatus Act by itself does not apply to the Navy or the Marine Corps.
https://www.history.navy.mil/research/library/online-reading-room/title-list-alphabetically/p/posse-comitatus-act-and-related-matters-a-sketch.html
Focus on the power of POTUS as it relates to the Marines.
How can MI be applied to prosecute bad actors and avoid corrupt agencies and judges?
Biggest drop on Pol.