Congress spoke clearly in 1878 when it passed the Posse Comitatus Act, prohibiting the use of the U.S. military to execute domestic law. Nearly 140 years later, Defendants -- President Trump, Secretary of Defense Hegseth, and the Department of Defense -- deployed the National Guard and Marines to Los Angeles, ostensibly to quell a rebellion and ensure that federal immigration law was enforced. There were indeed protests in Los Angeles, and some individuals engaged in violence. Yet there was no rebellion, nor was civilian law enforcement unable to respond to the protests and enforce the law.
Nevertheless, at Defendants’ orders and contrary to Congress’s explicit instruction, federal troops executed the laws. The evidence at trial established that Defendants systematically used armed soldiers (whose identity was often obscured by protective armor) and military vehicles to set up protective perimeters and traffic blockades, engage in crowd control, and otherwise demonstrate a military presence in and around Los Angeles. In short, Defendants violated the Posse Comitatus Act.
Almost three months after Defendants first deployed the National Guard to Los Angeles, 300 National Guard members remain stationed there. Moreover, President Trump and Secretary Hegseth have stated their intention to call National Guard troops into federal service in other cities across the country -- including Oakland and San Francisco, here in the Northern District of California -- thus creating a national police force with the President as its chief. Because there is an ongoing risk that Defendants will act unlawfully and thereby injure Plaintiffs, Governor Newsom and the State of California, the Court ENJOINS Defendants from violating the Posse Comitatus Act as detailed below.
[T]he Court ORDERS that Defendants are enjoined from deploying, ordering, instructing, training, or using the National Guard currently deployed in California, and any military troops heretofore deployed in California, to execute the laws, including but not limited to engaging in arrests, apprehensions, searches, seizures, security patrols, traffic control, crowd control, riot control, evidence collection, interrogation, or acting as informants, unless and until Defendants satisfy the requirements of a valid constitutional or statutory exception, as defined herein, to the Posse Comitatus Act.
-- US Judge for the Northern District of California Charles R. Breyer, ruling in Gavin Newsom, et al. v Donald Trump et al. that the administration violated the Posse Comitatus Act in its use of Federal and National Guard troops in California (2 September 2025)