In August 1889, a federal marshal named David Neagle walked into a railroad restaurant in Lathrop, California, and shot a man named David Terry to death. Neagle was guarding Supreme Court Justice Stephen Field. Terry had threatened to kill Field, and on that morning had just assaulted him. California arrested Neagle for murder.

The U.S. Supreme Court ordered him released. A state, the Court ruled, cannot prosecute a federal officer for acts he carries out while doing his federal job. Lawyers call it In re Neagle. The Court decided it in 1890. It has been the law ever since.

On Wednesday, the U.S. Court of Appeals for the Ninth Circuit cited Neagle again. This time against California's attempt to dictate how federal immigration officers identify themselves inside state lines. The panel was unanimous. The Biden Justice Department won a 2024 case on parallel ground when Texas tried to step into federal immigration enforcement.

Two states. Two years. The same constitutional clause. Only one inconsistent party: Democrats.

What the Constitution says when states disagree with Washington

The Supremacy Clause is the tiebreaker. It lives in Article VI of the Constitution. When state law and federal law conflict, federal law wins. The Founders wrote it into the document because they had just lived under a system where states could ignore national law, and that system did not work.

California passed SB 805, the "No Vigilantes Act," in September 2025. The ID rule made federal immigration officers working in California openly wear ID badges that showed their agency and either a name or badge number. California could send officers who failed to comply to jail.

The bill arrived dressed in public-safety language. The record tells a different story. For most of a decade, California has passed sanctuary laws designed to obstruct federal immigration enforcement, beginning with SB 54 in 2017 and expanding in every session since. SB 805 was the next move in that line: a state criminal law aimed squarely at federal officers California's political class opposes on principle. The "public safety" framing was the jacket. The obstruction was the argument.

When the same clause meant the opposite thing

On Wednesday, the Ninth Circuit granted the federal government an order blocking California from enforcing the ID rule while the appeal proceeds. The panel's opinion runs sixteen pages. The core holding reads:

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.

California asked the court to weigh that rule against the state's public-safety concerns. Judge Mark Bennett's three-word answer: "We decline to do so."

The Ninth Circuit is the most-reversed federal appellate court in the country and the court California runs to whenever it wants a Trump administration policy blocked. The panel Wednesday included two Trump appointees, Mark Bennett and Daniel Collins, and one Obama appointee, Jacqueline Nguyen. The vote was 3-0. Judge Nguyen did not write her own opinion. She did not concur. She did not attempt to carve an exception. She joined.

On January 3, 2024, the Biden Justice Department sued Texas over SB 4, that state's attempt to enforce immigration law against illegal entry. Attorney General Merrick Garland's lawsuit grounded the argument squarely in Article VI:

Under the Supremacy Clause of the Constitution and longstanding Supreme Court precedent, states cannot adopt immigration laws that interfere with the framework enacted by Congress. The Constitution assigns the federal government the authority to regulate immigration and manage international borders.

Texas argued that its law only helped enforce federal law. The Justice Department answered that help or harm, the Constitution does not permit a state to regulate in the federal government's immigration domain. The district court blocked SB 4. The appeals court above it refused to lift the block. Biden's Justice Department won. And Biden let the flood of illegal immigrants keep coming, telling states to simply deal with his border disaster.

The legal theories have different names. The constitutional rule is the same. That rule tells states they cannot move into a federal domain, as Texas tried, and cannot boss around federal officers inside that domain, as California tried. Two uses. One clause. Same losing argument: a state's policy choice cannot override what the Constitution gives Washington.

A pattern, not an accident

The Biden Justice Department did not invoke the Supremacy Clause once. It used it routinely, as a theory of how to govern.

Texas SB 8, the Heartbeat Act, September 2021: Garland's lawsuit said the law was "invalid under the Supremacy Clause" and "preempted by federal law." Idaho's abortion ban, August 2022: Justice sued, arguing the federal Emergency Medical Treatment and Labor Act overrode state law under Article VI. Georgia SB 202, June 2021: DOJ filed under the federal Voting Rights Act, claiming federal supremacy over state election administration.

And the Freedom of Access to Clinic Entrances Act, the federal law Biden prosecutors used to jail pro-life activists for sidewalk conduct that state prosecutors had declined to charge. Mark Houck, the pro-life activist acquitted in 2023 after a dawn FBI raid at his Pennsylvania home, got a formal admission this week that the Biden DOJ had violated his First Amendment rights. On Wednesday — the same day the Ninth Circuit ruled against California — the Department of Justice paid Houck more than a million dollars to settle his civil-rights lawsuit.

In each case, the logic was the same. Federal law is supreme. State law yields. Balance tests do not apply. That is not a conservative or progressive argument. It is a constitutional one. Democrats taught the country that constitutional lesson for four years. Now they get to hear it back.

A fake fight meets a real Constitution

California did not pass SB 805 because its lawyers believed the bill would survive a court challenge. The law's defenders spent seven months telling their base that the bill would rein in federal immigration agents, while anyone who could read Article VI knew the bill was dead on arrival. Judge Bennett's ruling confirmed what California's own counsel almost certainly told Sacramento in private: states do not get to throw federal officers in jail for doing their jobs.

The lower court tried to split the difference, asking whether California's law got in the way of federal work enough to merit blocking it. Judge Bennett flagged that move in direct terms: "The district court asked the wrong question."

That rule does not run on degree. It runs on category. If a state law tells federal officers how to do their jobs, it is void. Period.

California had real options if the concern was real. It could ask Congress to write federal identification rules. It could sue the Department of Homeland Security. It could pressure the White House. What it could not do is pass a state criminal law that puts federal officers in jail for how they wear their badges. That line was drawn in 1890. California knew that line was drawn in 1890. The bill was the performance; the court cleaned up the mess.

A ruling that was never in doubt

The Ninth Circuit issued an emergency order against SB 805 on February 19, less than two weeks before the in-court hearing. Courts do not do that unless they already see where a case is heading. Wednesday's ruling was the formal confirmation of a March 3 hearing that had already signaled the result.

And California did not appeal the district court's loss on the companion bill. A federal judge blocked the "No Secret Police Act" face-covering ban early on for the same constitutional reason. California chose not to fight that ruling. It fought this one. It lost both.

Democrats don't get to have it both ways

Democrats spent four years teaching the country that federal law wins when state law conflicts, no matter the state's reason, no matter the state's party. Texas heard it on abortion. Texas heard it again on the border. Idaho heard it on emergency medicine. Georgia heard it on election administration. Pro-life grandmothers and activists heard it with federal agents at their doors.

And now that the same clause has come back with California's name on the docket, Democrats would like a carve-out, an exception, a compromise, a policy conversation. They would like that same rule to mean one thing in January 2024 and something else in April 2026. They would like to claim federal supremacy when it punishes red states and states' rights when it protects blue ones.

The Ninth Circuit said no. A Trump appointee wrote the opinion. An Obama appointee joined it. An 1890 court case had said no in advance. The Constitution does not let one party have it both ways.

Same clause. Same answer. Same Constitution.