SAN FRANCISCO – A federal judge in San Francisco has intensified scrutiny on the Trump administration’s deployment of military personnel in Los Angeles, ordering both parties in a pivotal legal challenge brought by California to submit detailed briefings regarding potential violations of a key federal statute.
U.S. District Judge Charles Breyer, presiding over a federal courtroom, has mandated that legal teams representing both the State of California and the federal government provide their written arguments by noon on Monday, June 24, 2025. The core of the case centers on whether the presence and actions of the deployed troops contravene the Posse Comitatus Act, a Reconstruction-era law that generally prohibits the use of the U.S. military for domestic civilian law enforcement purposes.
Judge Breyer’s order came after he presided over a hearing on Friday, June 21, 2025, during which he reportedly posed pointed questions regarding the scope and nature of the troops’ activities in Los Angeles and their compliance with the Posse Comitatus Act. Following the hearing, Judge Breyer deferred issuing any immediate additional rulings, signaling the complexity and significance of the legal questions before the court.
California’s Legal Challenge and Gubernatorial Efforts
California initiated the legal challenge, arguing that the federal troop deployment in Los Angeles is unnecessary, counterproductive, and infringes upon state authority. The state’s efforts have been led by Governor Gavin Newsom, who is actively seeking a preliminary injunction to halt the deployment and regain state control over any National Guard units currently operating under federal direction.
Governor Newsom contends that the troop presence, authorized by President Donald Trump, has not only failed to restore order but has actively inflamed tensions within the community. He also argues that the deployment has usurped local authority traditionally held by state and local law enforcement agencies and has resulted in a waste of valuable resources.
This development in the federal district court follows a setback for Governor Newsom in a separate legal avenue. Just hours before Judge Breyer’s hearing, an appeals court denied the governor’s attempt to obtain a temporary restraining order aimed at immediately restoring state command over the National Guard troops involved.
The Posse Comitatus Act Under Scrutiny
The Posse Comitatus Act of 1878 is the central legal battleground in California’s challenge. Passed in the post-Civil War era, the act broadly restricts the use of the Army and Air Force (and by extension, other federal military branches through Department of Defense policy) from performing roles historically reserved for civilian law enforcement, such as arrests, searches, and seizures. Its purpose is to maintain a clear separation between the military and domestic police powers, a fundamental principle in U.S. governance.
The presence of federal troops, particularly in roles that appear to involve direct interaction with civilians in law enforcement-like capacities, raises significant legal questions under this act. Judge Breyer’s request for detailed briefings underscores the necessity for both sides to articulate their legal interpretations of the act and how it applies to the specific circumstances of the Los Angeles deployment.
Allegations of Troops’ Actions
California’s legal arguments are bolstered by specific instances cited regarding the activities of the deployed troops. Among the actions highlighted are reports of National Guard troops accompanying federal agents on immigration raids. While federal agents conducting immigration enforcement are within their jurisdiction, the involvement of military personnel in directly supporting such operations can raise questions about whether the military is being used in a capacity prohibited by the Posse Comitatus Act.
Further compounding these concerns is an incident where deployed Marines briefly detained a man. Direct detention of civilians by military personnel on U.S. soil in a law enforcement context is a particularly sensitive point under the act and is likely to be a focal point of the legal arguments presented to Judge Breyer.
Administration’s Justification and Local Context
The Trump administration has consistently defended the deployment, with President Donald Trump asserting that the troops are necessary to restore order in Los Angeles. The city has experienced periods of protests, sometimes leading to clashes, which the administration has cited as the justification for military intervention.
Meanwhile, the situation on the ground in Los Angeles has seen some shifts. Los Angeles Mayor Karen Bass recently lifted a downtown curfew that had been imposed following earlier protests and clashes. While the lifting of the curfew might suggest a de-escalation in some areas, the underlying tensions and the legal battle over the military presence persist.
Judge Breyer’s call for further legal arguments by the Monday deadline signals that the federal court is taking a careful and thorough approach to the complex constitutional and statutory issues raised by California’s challenge. The forthcoming briefings are expected to lay out the specific legal theories and factual interpretations that will inform the judge’s future decisions on the legality of the military deployment in Los Angeles.
