Legal Definitions - Posse Comitatus Act

The Posse Comitatus Act is a federal law that restricts the involvement of the Army or Air Force in civilian law enforcement activities. This means that these military branches cannot make arrests, conduct searches, or seize evidence in most cases.

The law was first passed in 1878 and applies only to the Army and Air Force. Members of the Navy, National Guard, and Coast Guard are not subject to the restrictions of the Posse Comitatus Act.

For example, if there is a riot in a city, the Army cannot be called in to help the police control the situation. Instead, the National Guard would be called upon to assist.

The Posse Comitatus Act is important because it helps to maintain the separation between the military and civilian law enforcement. This ensures that the military is not used to suppress the rights of citizens or to enforce laws in a way that is not consistent with the Constitution.