Why a federal judge’s LA ruling could limit Trump’s crime crackdown in other cities

In Washington, D.C., Trump has relied on the city’s unique legal status to deploy forces more freely, but extending the approach to states requires stronger justification

A US federal court ruling in California has dealt a setback to President Donald Trump’s domestic security agenda. Judge Charles Breyer concluded that the administration violated the Posse Comitatus Act, an 1878 law that bars federal troops from performing policing functions, when it deployed Marines and federalized National Guard forces in Los Angeles earlier this summer. The decision, scheduled to take effect September 12, prohibits troops from conducting arrests, searches, patrols, riot control, or similar activities, the New York Times reported.

Implications for Trump’s wider plans

The ruling threatens to complicate Trump’s threats to send federal troops into Democratic-run cities such as Chicago and Baltimore. In Washington, D.C., Trump has relied on the city’s unique legal status to deploy forces more freely, but extending the approach to states requires stronger justification. Breyer’s decision limits Trump’s ability to cite Los Angeles as a precedent for expanding his federal anti-crime operations.

Legal fight still unfolding

The Justice Department is expected to appeal, and higher courts could yet reverse Breyer’s order. An earlier attempt by the same judge to block Trump from federalizing the California National Guard was overturned on appeal. Still, if the ruling is upheld, it could impose legal guardrails on Trump’s ability to claim emergency authority for domestic deployments without invoking the Insurrection Act of 1807.

Political reactions across states

Democratic governors and attorneys general outside California quickly seized on the ruling as a national win. Massachusetts Governor Maura Healey called the Los Angeles deployment a “political stunt,” while Illinois Attorney General Kwame Raoul insisted there was no legal basis for sending troops to Chicago. Illinois Governor J.B. Pritzker was more blunt, rejecting Trump’s suggestion that governors should “beg” for military aid and warning that such demands undermine democratic norms.

Trump’s defiance and ongoing threats

Despite the setback, Trump doubled down in remarks from the Oval Office, denouncing Chicago and Baltimore as “hellholes” plagued by crime and reiterating his willingness to send in troops. He framed the deployments as offers of assistance that governors should accept, though his critics saw them as threats to federalize policing and weaken state authority.

The Insurrection Act question

Trump has so far avoided invoking the Insurrection Act, which allows presidents to use troops in emergencies such as rebellion or invasion, perhaps out of concern that courts could scrutinize whether the legal conditions were truly met. Breyer suggested that the administration’s reluctance reflected its inability to prove local authorities were unwilling or unable to enforce the law in Los Angeles. The last time the act was used was in 1992, during riots after the Rodney King verdict, and only at the request of California’s governor.

Judge warns of systemic violations

In his opinion, Breyer accused Trump and Defense Secretary Pete Hegseth of orchestrating “a top-down, systemic effort to use the military to perform law enforcement functions.” He found that once troops were deployed in Los Angeles, they went far beyond protecting federal buildings, joining drug enforcement raids, blocking roads, and carrying out crowd control. Such conduct, he ruled, was a “serious violation” of federal law.

Next steps in Los Angeles

Around 300 National Guard troops remain under federal control in Los Angeles, but Breyer ruled they may only be used to safeguard federal property in compliance with the Posse Comitatus Act. He did not provide detailed guidance on what specific activities are allowed under that standard, leaving room for further disputes over implementation.