Federal judge blocks warrantless immigration arrests in Southern California unless escape likely

LOS ANGELES -- A federal judge has issued an order blocking immigration officers from making warrantless arrests in Southern California unless they determine the person is likely to escape.

In a preliminary injunction granted Sept. 2 and unsealed Wednesday, U.S. District Judge Maame Ewusi-Mensah Frimpong said the government must consider the “totality of the circumstances known to the agent or officer” regarding a person's likelihood of escape before making a civil immigration arrest without a warrant.

The lawsuit was filed last fall by the American Civil Liberties Union of Southern California, Public Counsel, and Los Angeles immigrant advocacy groups during an unprecedented surge of immigration enforcement in the region. The order applies in the Central District of California, which includes Los Angeles, Orange, Riverside, San Bernardino, Ventura, Santa Barbara and San Luis Obispo counties.

Frimpong also ordered the government to thoroughly document the probable cause that leads to an arrest before a warrant could be obtained. The mere fact that someone is in the country illegally is not enough to justify a warrantless arrest, she said in her order.

“Without this, Defendants cannot show that any arrest was proper,” Frimpong wrote. She denied the government's request to stay or delay the order to give them time to appeal.

The U.S. Department of Homeland Security did not immediately respond to a request for comment.

The lawsuit also sought to block roving patrols making stops and arrests based solely on race, language and occupation, and to protect access to counsel rights for people in detention.

Frimpong previously issued a temporary restraining order to restrict these sweeping immigration operations, but it was lifted by the U.S. Supreme Court last September. Justice Brett Kavanaugh said apparent ethnicity could be a relevant factor for a stop if combined with other information.

The unsealed preliminary injunction on warrantless arrests was issued after a hearing Aug. 13 where Frimpong signaled in a tentative ruling she was inclined to side with the plaintiffs.

Federal judges in Portland, Colorado, Washington, D.C., and the Eastern District of California have already blocked similar warrantless arrest practices.

Plaintiffs argued in court documents that in many arrests they tracked in Southern California, no documentation was ever produced showing the arresting officers documented the likelihood of escape.

“There's no statutory requirement to document,” said federal attorney Daniel Mummolo, adding that different arresting officers handle things differently.

He cited a memo issued in January 2026 by former acting director of U.S. Immigration and Customs Enforcement Todd Lyons that said officers could make an “on-the-spot” determination about likelihood of escape.

“You have not presented evidence of officers saying, ‘Yeah I didn’t write it down but I did do it,' ” Frimpong said in response.

Plaintiffs' attorney Laura Perry Stone said the memo requires officers to determine both that the person was likely to leave the location and is unlikely to be found at another identifiable location, such as their home or workplace.

In her order, Frimpong said that a “wealth of record evidence” including government directives, arrest narratives, agent depositions and video evidence showed the government's current policy and practice was to conduct an escape risk assessment based solely on unlawful status or “false assertions,” or to not conduct one at all.

In one instance, the government claims that an individual was “running away” from immigration agents before being questioned. But a video of the arrest showed him walking at a normal pace and texting on his phone before the agent began questioning him, Frimpong wrote.

“This court order should put an end to hundreds – if not more – of unlawful arrests that continue throughout Southern California,” said Mayra Joachin, an attorney with the ACLU of Southern California. "We will closely monitor compliance with this court order, and expect the federal government to abide by it.”