Gavin Newsom’s legislative minions just got a lesson in constitutional supremacy

California's "No Vigilantes Act," signed into law by Governor Gavin Newsom in 2021, explicitly prohibited state and local law enforcement from cooperating with federal Immigration and Customs Enforcement agents unless ICE obtained a judicial warrant—not just an administrative detention order. The law reflected a strategy adopted by California and several other sanctuary jurisdictions to starve federal immigration enforcement of local assistance. The Ninth Circuit Court of Appeals, in a decision released this week, unanimously ruled the law unconstitutional under the Supremacy Clause, finding that states cannot obstruct federal immigration authorities from doing their jobs, even through facially neutral law enforcement procedures.

This isn't academic. California has over 2,700 local law enforcement agencies. Under the law, when ICE agents wanted to detain someone during a traffic stop or at a local jail, state officers were forbidden from holding that person past their normal release date or providing any assistance. The practical effect was that ICE agents had to conduct their own arrests without local infrastructure—jails, transport, holding cells—creating a significant friction on federal enforcement capacity. Newsom's administration projected this would protect undocumented immigrants from what it called "vigilante" deportations, a framing the law's name was meant to evoke.

The Ninth Circuit's reasoning cuts to something fundamental: federal immigration law is exclusively federal jurisdiction. When a state passes a law that effectively prevents federal agents from executing federal law, it conflicts with the Constitution's Supremacy Clause. The court noted that California couldn't use neutral police procedures as a backdoor way to obstruct federal priorities. One judge wrote that allowing such obstruction would mean states could nullify any federal enforcement they disliked simply by refusing to help—a principle that, if extended, would eviscerate federal authority across dozens of domains.

The conservative position here is straightforward: states have no right to conduct shadow immigration policy through the back door of local police procedures. Immigration is federal law. If California disagreed with federal policy, the avenue was Congress or the courts, not systematic obstruction of federal agents. Newsom's law was packaged as protecting civil liberties, but its actual mechanism was states' rights activism dressed in social justice language—using local police as a tool to nullify federal law. The court's decision reaffirms that federalism has limits; a state can't simply declare it won't participate in federal enforcement.

Watch for whether California appeals this to the Supreme Court—unlikely to succeed given the unanimous Ninth Circuit decision and established precedent, but it would signal doubling down. More immediately, watch whether other sanctuary cities attempt similar laws knowing they'll face the same fate, and whether the Biden administration's DOJ actually enforces this ruling or quietly lets it sit. The real test is what ICE does next: if they increase operations in California now that they have clearer legal ground, the impact on immigrant communities will be direct and measurable. That enforcement surge, or lack thereof, is the actual consequence of this ruling.