The Posse Comitatus Act is a federal law enacted in 1878

[elleng]

that generally prohibits the use of active-duty U.S. military forces for domestic civilian law enforcement activities, such as making arrests or conducting searches. Enacted in response to the post-Civil War use of the military for law enforcement, it serves as a guardrail to maintain the separation of the military from civilian affairs. However, numerous exceptions exist, including authorizations by Congress for specific functions like counterdrug operations and the use of the military in emergencies involving weapons of mass destruction.

[intelpug]

1. posse comma titus

Don't know all the particulars but do know even into the late twenties national guard was used as a police force during coal mine strikes, My grandmother vividly remembered them coming to town in Wyoming every time the union called a strike

[elleng]

2. Interesting history