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A federal appeals court on Wednesday struck down California’s requirement that masked federal agents identify themselves, a blow to the state’s ongoing resistance to the Trump administration’s deportation program.
A 9th U.S. Circuit Court of Appeals panel handed down a ruling prohibiting California from enforcing a section of the 2025 mask law that mandates federal law enforcement officers visibly display identification while carrying out their duties.
The law was destined to face critical scrutiny from the federal judiciary. An 1890 Supreme Court case provides that a state cannot prosecute federal law enforcement officers acting in the course of their duties.
The law also ran headlong into the Supremacy Clause of the Constitution, which holds that states may not regulate the operations of the federal government.
The Trump administration sued to challenge the law soon after Gov. Gavin Newsom signed it. On Feb. 19, a federal judge issued an injunction against the mask law. The new ruling by a 3-0 decision makes that injunction permanent, pending appeal.
“If a state law directly regulates the conduct of the United States, it is void irrespective of whether the regulated activities are essential to federal functions or operations, and irrespective of the degree to which the state law interferes with federal functions or operations,” wrote judge Mark J. Bennett.
California’s lawyers argued that, even if the mask law does violate the Supremacy Clause, the court should have also considered the state government’s concerns about federal immigration enforcement’s effect on public safety.
“We decline to do so,” Bennett wrote. “Because the United States has shown a likelihood that the Act violates the Supremacy Clause, it has also shown that both the public interest and balance of the equities tip ‘decisively in…favor’ of a preliminary injunction.”
Democrats passed the mask ban to rein in the anonymous federal agents carrying out the Trump administration’s aggressive immigration enforcement program.
Lawmakers this year are advancing more bills targeting the administration’s immigration agents, including proposals that would bar them from employment in California law enforcement agencies and a measure that would make it easier for people to sue federal agents over civil rights violations.



