Newsom and Trump face off in trial over National Guard in L.A.

The Trump administration and California will face off in court Monday, over President Donald Trump’s decision to deploy the National Guard and Marines in Los Angeles.

Trump sent the troops to Los Angeles to address protests against immigration arrests in the city. Most of the troops have been recalled but a ruling in favor of California could hamstring the president’s ability to respond to domestic emergencies, the government argues.

California sued Trump in June, after clashing with the president over how best to respond to protests in downtown Los Angeles over the president’s immigration raids. Trump deployed about 4,000 National Guard troops, ordering them to the streets under federal control, over Governor Gavin Newsom’s objections. Trump also sent about 700 active-duty Marines to the city.

Over a three-day trial in San Francisco, US District Judge Charles Breyer will hear testimony and legal arguments to determine whether the deployment violated the Posse Comitatus Act, a federal law that sharply limits members of the military from enforcing civilian laws.

“It doesn’t seem like we’re on the threshold of mass violence and chaos,” said Jon Michaels, a professor at the University of California, Los Angeles law school. “The city didn’t feel dangerous. But is that a decision for me to make? Is that a decision for Gavin Newsom to make? Is that a decision for Judge Breyer to make? Or is it up to federal officials? Whoever ultimately gets to make that decision dictates how this case comes out.”

Newsom and LA Mayor Karen Bass, both Democrats, said troops weren’t needed and their presence inflamed tensions. Newsom said the troops were diverted from more important duties, including wildfire suppression and helping battle drug smuggling at the Mexican border.

The trial starts days after Trump told reporters he was considering deploying the National Guard to address crime in the city of Washington. That came in response to a late-night assault on a DOGE staffer during a carjacking attempt.

Earlier this year, Breyer ordered Trump to return the National Guard to Newsom’s control, but a federal appeals court in San Francisco put a hold on the order, ruling that Trump had likely acted within the law.

‘Great Significance’

This week’s proceedings are about whether federal troops were illegally used for traditional law enforcement activities, according to Erwin Chemerinsky, the dean of the law school at the University of California, Berkeley.

“With President Trump increasingly talking about using troops for law enforcement purposes, this trial has great significance,” Chemerinsky said.

A win for Trump could be seen as a green-light for presidents to unilaterally employ the military to police citizens inside the US.

The Trump administration has argued that the president has broad, unilateral power to federalize the National Guard when he determines there is a “rebellion” or “invasion” or when “regular forces” are unable to enforce the law. A lawyer for the state called the prospect that a president can order troops into US cities without court review “terrifying.”

The case may ultimately be decided by the US Supreme Court, long after the troops have left Los Angeles. Nearly all have now been recalled, with just a small contingent left to stand guard at some federal facilities.

The case is Newsom v. Trump, 25-cv-04870, US District Court, Northern District of California (San Francisco).