The Trump administration will send over 100 federal immigration agents to the Bay Area on Thursday. 

The agents are reportedly from several agencies including Customs and Border Protection, which traditionally is deployed at the border but has been sent farther afield by President Donald Trump. News of the arrival of these agents came after Trump had threatened to send National Guard troops to San Francisco, saying he has “unquestioned power” to do so. 

National Guard troops deployed to the Bay Area would not be able to make immigration arrests. They could, however, offer “cover” for CBP agents who are doing so. This has already taken place in other cities. 

In Chicago, Texas National Guard Troops were instructed to protect ICE agents and buildings.

In Los Angeles, troops carrying shields and armed with rifles stood in front of federal buildings and accompanied ICE agents on raids. They escalated tensions by giving protesters a subject to face off with, Los Angeles Times reporter Rebecca Ellis said in an interview with Oregon Public Broadcasting. 

It’s possible members of the National Guard in San Francisco would be stationed around federal immigration buildings at 100 Montgomery or 630 Sansome St., where the bulk of immigration arrests in San Francisco have taken place.

Still, unlike ICE or CBP agents, which can largely operate with a free hand, legal experts said National Guard troops deployed to California cannot make arrests without a warrant. Under the Posse Comitatus Act, federal troops must be authorized by the governor to participate in law enforcement against civilians. 

That is unlikely to happen locally. Gov. Gavin Newsom has been outspoken against Trump’s deployment.

“He sends out masked men, he sends out border patrol, he sends out ICE. It creates fear and anxiety in the community so that he can lay claim to solving for that by sending in the guard,” Newsom said in a video posted on X. “This is no different than the arsonist putting out the fire.” 

A federal judge ruled in June that deploying the California National Guard to participate in civilian law enforcement without Newsom’s consent was illegal. By the end of July, all but 300 of the National Guard troops who had been deployed in Los Angeles were sent home. 

Trump has intimated that he would invoke a different law, the Insurrection Act of 1807, to deploy troops to San Francisco. This would allow soldiers to enforce a federal court order, like a U.S. Supreme Court ruling, or suppress an “uprising.” 

In most cities, however, National Guard troops are focused on more mundane tasks. In Washington, D.C., where Trump deployed the National Guard back in August, troops have been shoveling mulch, picking up trash, and patrolling train stations. They’ve also asked city leaders for other “beautification” projects to work on. 

“We collected approximately 40-plus trash bags with several pieces of debris, some old tires and crates,” said Bernard Aguon, command chief warrant officer of the D.C. Army National Guard, in a statement to the U.S. Department of Defense. “Our goal here is really just to help the community by beautifying areas within the district.” 

San Francisco, for its part, is already planning to take legal action if the guard is deployed here, and has joined a coalition of other jurisdictions urging the U.S. Supreme Court to keep the National Guard from Chicago and other cities.

“We don’t exactly know what the federal government is planning in San Francisco and across the Bay area, but we do know this federal administration has a playbook in cities across the country,” Mayor Daniel Lurie said on Wednesday. “I want to be very clear: We are prepared.”