On 14 October, a federal judge's ruling in the dispute between California and the Trump administration came down against the state, centring on what identification documents federal immigration officers are obligated to carry. A Ninth Circuit panel instructed a district court to halt enforcement of the state's No Vigilantes Act as it applies to federal agents.
Officers without uniforms were required, under that statute, to make their identification visible when carrying out enforcement activities, though certain exemptions applied. The court found that California had acted beyond its constitutional boundaries by attempting to regulate federal activities without congressional authorisation.
The ruling's scope stops well short of judging whether immigration enforcement operations themselves hold up under the law — what it settles is a narrower constitutional question about the limits of state authority over federal agents, leaving those operational legality questions for another forum.
A Justice Department complaint lodged in November 2025 — listing California, Governor Gavin Newsom, and Attorney General Rob Bonta among the named defendants — formed the basis for that ruling. Under the US Constitution's Supremacy Clause, states are barred from imposing direct regulatory burdens on federal government operations — a principle that sat at the heart of the challenge federal officials mounted against the identification requirement.
Passed under the name No Vigilantes Act and taking effect in September 2025, the law required plainclothes law enforcement personnel to carry and show identification bearing both their agency affiliation and either a name or a badge number. Under that provision, federal agents conducting operations within California — a group that encompassed Immigration and Customs Enforcement staff — were bound by its terms. Any officer who intentionally violated the provision with full knowledge of doing so would be subject to criminal penalties under state law.
Narrow carve-outs were built into the law, and agencies retained a path to compliance by publicly posting identification policies that met the specified requirements. A ruling issued by the Ninth Circuit on 14 October held that Section 10 of the statute placed direct restrictions on federal law enforcement operations without authorisation from Congress, with the court noting in its written opinion that the provision overrode the federal government's authority to decide whether, when, and in what manner its officers are identified to the public.
The state's legal position held that day-to-day federal functions faced no meaningful disruption from the provision in question. Dismissing the argument that the degree of interference mattered, the three-judge panel held that a state's direct regulation of federal government operations was sufficient grounds on its own to invalidate such action. The panel took the view that the administration's constitutional argument was likely to prevail.
The appellate panel overturned the lower court's denial of preliminary relief, directing that tribunal to put in place an injunction barring California from applying the contested requirement to federal officers. The decision bolsters the government's position in the litigation, though what the court weighed was only a preliminary injunction — not a final resolution of the broader claims at the heart of the dispute.
State authorities in California took issue with the decision, contending that officers carrying out immigration enforcement were obligated to display identifying markers as a matter of both public accountability and operational transparency. A statement from Bonta's office conveyed disappointment with the ruling and noted that attorneys there were examining the opinion in detail. The written submission contended that when officers withhold their identities, trust between the public and policing agencies stands to erode.
On an earlier occasion, the state's top law enforcement officer put forward the view that the measure served as a protection against anonymous actors working within California's communities. Transparency and accountability in policing were described as foundational to the office's effective operation. Newsom's office also took issue with how federal authorities have been carrying out immigration enforcement, arguing that the approach has placed strain on families and communities.
The appeals court ruling drew expressions of approval from federal officials. Two officials from the Department of Justice offered their reactions to the ruling, with Brett Shumate, serving as Assistant Attorney General, expressing approval and Stanley Woodward, in his role as Associate Attorney General, characterising the outcome as a win for federal law enforcement. The administration's stance, as conveyed through those responses, held that congressional authorisation governed how federal officers performed their duties — not mandates from California.
The Ninth Circuit ruling built on prior orders that had already barred California from applying the identification requirement to federal officers. At the district court level, the provision had faced no immediate injunction. On 19 February 2026, a temporary administrative injunction from the appellate court put enforcement on hold while proceedings in the case moved forward. A temporary injunction pending appeal was put in place by the court, with that order taking effect on 22 April.
The October appellate decision overturned the lower court's refusal to grant preliminary relief and ordered the trial court to issue a preliminary injunction. Among the provisions facing legal challenge was California's No Secret Police Act, a state measure placing limits on the wearing of masks and other face coverings by officers in law enforcement roles. That restriction had been placed under an injunction by a district-level judge, barring its application to federal officers.
Provisions relating to masks fell outside the scope of the October appeal, which addressed only the identification requirement contained in the No Vigilantes Act. Identification requirements tied to state or local law enforcement personnel also fall outside the scope of what the ruling addresses. Federal officers retain whatever distinct duties arise under federal law, independent of what that provision addresses.
The legislation in California took shape against a backdrop of community concern over enforcement actions targeting immigrants and reports of federal agents operating without visible identification. Proponents contended that requiring officers to carry and display identification would give residents a way to verify whether personnel were authorised, while also strengthening oversight of how enforcement activities were conducted.
The ruling leaves intact the administration's authority over how its personnel may present their official identities while on duty. In California, the ruling bars the state from putting into effect the law aimed at making immigration operations more visible to the public. No resolution has been reached on the wider disagreement. On a provisional basis, the appeals court has moved to halt the state identification requirement, though the wider body of federal enforcement practices remains intact and the contested questions around immigration policing and accountability have yet to be addressed.
