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

California's "No Vigilantes Act," formally SB 1159, prohibited private security contractors—including those hired by Immigration and Customs Enforcement—from detaining people on suspicion of immigration violations. Enacted in 2019, the law allowed only state and local peace officers to make immigration-related arrests. A three-judge panel of the Ninth Circuit Court of Appeals, hardly a conservative stronghold, unanimously ruled the law unconstitutional on June 7, 2024, finding it violated the Supremacy Clause because it conflicted with federal immigration enforcement authority. The ruling means ICE can continue using private security contractors like CoreCivic in immigration enforcement operations across California, which had become a testing ground for sanctuary state policies.

The practical consequence is immediate: ICE regains the ability to deploy private detention contractors for immigration operations in the nation's most populous state, potentially expanding enforcement capacity without adding federal employees. CoreCivic and other private security firms can now legally participate in immigration sweeps, apprehensions, and detention in California. For immigrants and advocacy groups, this eliminates what they viewed as a crucial barrier to enforcement. For ICE, it removes a jurisdictional constraint that had forced operational workarounds. For Newsom's administration, which championed the law as a rebuke to Trump-era immigration enforcement, it represents a hard constitutional limit on how far a state can restrict federal enforcement within its borders.

The Supremacy Clause precedent here echoes United States v. Arizona (2012), when the Supreme Court struck down most of Arizona's SB 1070 on similar grounds—that states cannot regulate immigration enforcement, only the federal government can. That decision appeared settled law, yet California tested it anyway with a narrower vehicle: instead of creating immigration crimes, California restricted who could enforce existing federal law. The Ninth Circuit rejected the distinction. States cannot use their regulatory authority over contractors to indirectly regulate federal immigration enforcement.

The conservative reading is straightforward: California tried to legislatively nullify federal law by blocking the tools federal agents could use. Congress passed immigration statutes. ICE has statutory authority to enforce them. Newsom's legislature decided those laws shouldn't apply on California soil—not by changing immigration policy itself, which they lack power to do, but by handcuffing the agency charged with enforcement. The Ninth Circuit caught the sleight of hand. States don't get to unilaterally secede from federal law enforcement. If California wants different immigration policy, it can lobby Congress or fund alternative programs, but it cannot constitutionally tell federal agencies which lawful enforcement methods they're barred from using. The ruling forces California to accept the trade-off it avoided: if you want to reject federal enforcement philosophy, you face the political cost of that stance, not constitutional workarounds.

The immediate next step is whether California appeals to the full Ninth Circuit or, more likely given the panel's unanimity and the settled Supremacy Clause doctrine, how Newsom's legislature responds. ICE has already signaled it intends to resume using CoreCivic and other private contractors in the state. Watch for whether California attempts a narrower legislative fix—perhaps restricting contractors based on different rationales unrelated to immigration—or whether it pivots to funding its own detention alternatives to reduce ICE's operational incentive. The legislature reconvenes in January 2025, giving it several months to strategize. If federal immigration enforcement intensifies under a new administration, this ruling becomes a pressure point: California's constraints have just been stripped away.