The Posse Comitatus Act (18 U.S.C. § 1385) bars the federal military from enforcing domestic laws unless Congress specifically authorizes it. Passed after Reconstruction to prevent military occupation of Southern states, it remains a foundational limit on executive power. The Insurrection Act is its primary exception.
The Posse Comitatus Act is a check on executive power: the military can't simply become the police. When civil unrest or disaster strikes, leaders might want military force to restore order. The Act forces them to use civilian law enforcement or get explicit congressional authorization, protecting civilians from military rule.
People often think the Posse Comitatus Act prohibits all military involvement in law enforcement. Actually, there are exceptions—the Insurrection Act allows military deployment to suppress rebellion or invasion, and many laws authorize military support to civilian agencies in specific circumstances.
The Posse Comitatus Act is a check on executive power: the military can't simply become the police. When civil unrest or disaster strikes, leaders might want military force to restore order. The Act forces them to use civilian law enforcement or get explicit congressional authorization, protecting civilians from military rule.
People often think the Posse Comitatus Act prohibits all military involvement in law enforcement. Actually, there are exceptions—the Insurrection Act allows military deployment to suppress rebellion or invasion, and many laws authorize military support to civilian agencies in specific circumstances.