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

California legislators learned a hard lesson about constitutional hierarchy this week when a three-judge panel of the Ninth Circuit—hardly a conservative court—unanimously gutted the state's signature immigration enforcement restriction. The "Defend California Act," formally known as Senate Bill 54, passed in 2017 with overwhelming Democratic support and made it state law that local police and sheriff's deputies could not cooperate with federal Immigration and Customs Enforcement without a judicial warrant. The law effectively turned California into a sanctuary state by prohibiting state and local resources from being used in immigration enforcement. On Tuesday, the court ruled the law unconstitutional under the Supremacy Clause, the constitutional provision that establishes federal law as the supreme law of the land when states attempt to restrict it.

The immediate practical effect is stark: California can no longer legally prohibit its law enforcement officers from communicating with ICE or assisting in immigration operations. The ruling means ICE agents can now access California jails and courthouses without the state actively working to block them—a seismic shift for a state that has spent seven years operating under the assumption that its restrictions were constitutional. The state had invested substantial resources into enforcement mechanisms designed to shield undocumented immigrants from federal deportation proceedings. School districts were told not to cooperate with ICE. Hospitals received guidance limiting access to patient information. Sheriffs in progressive counties explicitly refused ICE requests. All of that rests on shakier legal ground now, though how aggressively federal enforcement intensifies remains an open question.

The Ninth Circuit's reasoning was unusually direct for a panel that typically explores every available constitutional wrinkle. The judges found that when federal law explicitly authorizes ICE to enforce immigration statutes, a state cannot use its own police powers to obstruct that federal function. This is distinct from earlier sanctuary city litigation where courts had to grapple with whether states could affirmatively refuse cooperation—the unanimous panel here suggested even passive obstruction violates the Supremacy Clause. The decision creates immediate tension with other rulings protecting sanctuary policies in places like New York, where courts had concluded state law couldn't be forced to affirmatively assist federal enforcement, only that it couldn't prohibit it.

The conservative read here is straightforward: California's Democratic leadership tried to nullify federal immigration law through state statutes, and they got caught. SB 54 was never about enhancing public safety or respecting federalism—it was about undermining the enforcement of laws the legislature disagreed with. The Ninth Circuit's own unanimity reveals this wasn't a close call or a matter of legitimate constitutional interpretation. The state essentially attempted what the South did with civil rights laws: use state machinery to frustrate federal statutory authority. That it took seven years and a federal court to stop it reflects the practical reality that sanctuary policies work through obstruction when legal challenges move slowly. What's instructive is that even a court known for expansive readings of state power found no constitutional basis for this one.

What to watch: California will likely appeal to the full Ninth Circuit or petition the Supreme Court, but the unanimity of this panel decision—particularly with judges appointed by both Democratic and Republican presidents—makes reversal unlikely at higher levels. The more significant next step is how the Biden administration's Justice Department responds and whether it seeks to enforce the ruling aggressively against California officials who continue SB 54 compliance policies. If Trump takes office in 2025 as polls suggest possible, expect a Justice Department that actively uses this ruling as legal cover for expanded ICE access to state facilities. The state's sanctuary infrastructure—built over years—could collapse within months of a new administration taking office.