LOS ANGELES (AP) — A federal appeals court issued an order Wednesday blocking a California law requiring federal immigration agents to wear identification, another blow to the state’s attempts to limit the Trump administration’s aggressive enforcement tactics.
The Trump administration argued that it would threaten the safety of officers who are facing harassment, doxing, and violence and that it violated the constitution because the state was directly seeking to regulate the federal government.
A three-judge panel of the 9th U.S. Circuit Court of Appeals issued an injunction pending appeal. It had earlier blocked the law from taking effect.
The decision could have implications nationwide for other states that have pursued their own measures to place restrictions on immigration agents.
The measure was one of two major pieces of legislation enacted last fall aimed at reining in federal immigration agents after a sweeping crackdown on illegal immigration in Southern California in June. The other law would have banned most law enforcement officers from wearing masks, neck gaiters, and other facial coverings. Advocates have raised concerns about masked agents conducting workplace raids or arresting people on the street, often without showing identification.
The Trump administration sued over both in November.
A federal judge blocked the mask ban in February, ruling that it discriminated against the federal government because it did not apply to state troopers. The law made exceptions for undercover agents, protective equipment like N95 respirators or tactical gear, and other situations where not wearing a mask would jeopardize the operation. That judge let the ID law stand.
At an appeal hearing March 3, Justice Department lawyers argued that the California identification requirement law sought to regulate the federal government, violating the Supremacy Clause of the Constitution.
The appeals court agreed unanimously, saying the law “attempts to directly regulate the United States in its performance of governmental functions,” in an opinion written by Judge Mark J. Bennett. The panel was composed of two Trump appointees, Bennett and Daniel P. Collins, and Obama appointee Jacqueline H. Nguyen.
California lawyers argued that the law applied equally to all law enforcement officers without discriminating against the U.S. government, and that states could apply “generally applicable” laws federal agents. They also argued that the law was important to address public safety concerns.
People are more likely to attack officers in self-defense if there’s no visible identification letting the public know they are law enforcement, California lawyers said in a brief.
“This confusion has resulted in federal law enforcement officials being mistaken for criminals and vice versa, creating serious risk of harm to peace officers and members of the public,” they wrote.
In October 2025, the Federal Bureau of Investigation issued a report warning that the increase in U.S. Immigration and Customs Enforcement activity had spurred “criminal actors impersonating ICE agents to commit violent crime,” California attorneys noted.
The appeals court judges said they did not consider the public safety factors because the federal government has demonstrated its constitutional rights would be violated by the legislation, and “all citizens have a stake in upholding the Constitution.”
When a lower court struck down California’s mask ban, it left open another way of achieving the same goal. The judges in that case had indicated they would be more open to a law that banned masks for all law enforcement officers, not just federal ones. A new California bill attempts to revive the mask restrictions by also applying them to state troopers.
But the appeals court’s opinion signals a stricter view on the state government’s ability to regulate federal officers.
“The Supremacy Clause prohibits States from enacting a law that directly regulates federal operations even if the law regulates state operations in the same manner,” the judges wrote.
First Assistant U.S. Attorney Bill Essayli called it a “huge legal victory” in a post on X.
California Attorney General Rob Bonta’s office said they are reviewing the order.
“The Trump Administration has stepped well outside the boundaries of normal practice, deploying masked and unidentified agents to carry out immigration enforcement, despite the risks these tactics pose to public safety and basic civil liberties,” Bonta’s office said in a statement.