A federal officer shot and killed a woman in Minneapolis on Wednesday, shortly after the Trump administration deployed thousands of immigration agents to the city. Although the full circumstances of the killing remain unclear, video of the shooting shows an officer opening fire on the woman as she drove away.

Realistically, there’s virtually no chance that President Donald Trump’s Justice Department will bring federal charges against the officer who killed this woman. Trump already claimed on TruthSocial, his personal social media site, that the officer shot the woman in “self defense.” (The officer could potentially be prosecuted after Trump leaves office.)

But many local officials are quite upset about this incident. Minneapolis Mayor Jacob Frey gave a press conference Wednesday afternoon where he told US Immigration and Customs Enforcement to “get the fuck out of Minneapolis.” If further investigations reveal that the shooting was not legally justified, state prosecutors could potentially charge the officer responsible with a homicide crime.

The Supreme Court’s Republican majority has made it very difficult for private citizens to sue federal law enforcement officers who break the law. But can a federal officer actually be charged with, and convicted of, violating a state criminal law?

Until fairly recently, the law was favorable to federal officials who allegedly violate state criminal laws while they carry out their official duties. The seminal case, known as In re Neagle (1890), held that a deputy US marshall who shot and killed a man could not be charged with murder in state court, because this federal officer did so while acting as a bodyguard for a US Supreme Court justice.

Last June, however, the Supreme Court handed down Martin v. United States (2025), which held that Neagle does not always protect federal officials who violate state law. The rule announced in Martin is vague, so it is unclear how it would apply to the shooting in Minneapolis. But the gist of the ruling is that a federal officer is only protected if they can demonstrate that “their actions, though criminal under state law, were ‘necessary and proper’ in the discharge of their federal responsibilities.”

If the officer responsible for the Minneapolis killing broke Minnesota law, in other words, any prosecution against them would turn on whether the courts decide shooting this woman was a “necessary and proper” exercise of the officer’s official duties.

There is one other potential complication. A federal law provides that state criminal charges against “any officer (or any person acting under that officer) of the United States or any agency thereof” may be removed from state court and heard by a federal judge. This statute does not prevent state prosecutors from bringing charges or from prosecuting a case. But it does ensure that the question of whether Neagle applies to this case would be decided by federal courts that are increasingly dominated by conservative Republicans.

Federal cases out of Minnesota appeal to the United States Court of Appeals for the Eighth Circuit, a very conservative court where 10 of the 11 active judges were appointed by Republicans. And, of course, any decision by the Eighth Circuit might be appealed to the Supreme Court, where Republicans control six of the nine seats.

All of which is a long way of saying that, while the law does not absolutely preclude Minnesota prosecutors from filing charges against this officer, it is far from clear that those charges will stick.

When are federal officers immune from prosecution in state court?

The facts underlying the Neagle case are simply wild. David Terry was a lawyer and former chief justice of the state of California, who had served with US Supreme Court Justice Stephen Field while the two were both state supreme court justices. At the time, federal justices were required to “ride circuit” and hear cases outside of Washington, DC. And so, Field wound up hearing a dispute about whether Terry’s wife was entitled to a share of a US senator’s fortune.

At the court proceeding, where Field ruled against Terry’s wife, Terry punched a US marshal, brandished a bowie knife, and was jailed for contempt of court. After his release, he and his wife continued to threaten Field’s life, and so, the attorney general ordered Deputy Marshal David Neagle to act as Field’s bodyguard.

Then, Terry attacked Field while Field was traveling through California by train, and Neagle shot and killed Terry.

Given these facts, it’s unsurprising that the Supreme Court ruled that California could not bring charges against Neagle for this killing. The case involved a physical attack on a sitting justice! And, besides, Neagle acted within the scope of his responsibilities as Field’s federally appointed bodyguard.

135 years later, however, the Court decided Martin. That more recent decision focused on language in the Neagle opinion that suggested that its scope may be limited. Neagle, Justice Neil Gorsuch wrote in Martin, arose from concerns that “California could frustrate federal law by prosecuting a federal marshal “for an act which he was authorized to do by the law of the United States.” Protecting Field was something that “it was [Neagle’s] duty to do.” And, in shooting Terry, Neagle “did no more than what was necessary and proper.”

Thus, Gorsuch extracted a rule from Neagle that federal officials are only protected from state law when their actions “were ‘necessary and proper’ in the discharge of their federal responsibilities.”

In the wake of Martin, Minnesota may very well be able to prosecute the officer responsible for the Minnesota killing. As a general rule, federal law enforcement officers are not authorized by the law of the United States to shoot people without justification. So, if it turns out that this killing was legally unjustified, federal courts may conclude that the officer’s actions were not necessary and proper in the discharge of his official duties.

That said, Martin is a fairly new opinion, and the rule it announced is vague. And any prosecution against a federal immigration officer would be unavoidably political. So, it is unclear whether the judges who hear this case would approach it as fair and impartial jurists or as partisans.

The bottom line, in other words, is that the law governing when federal officers may be charged with state crimes is quite unclear. So, it is uncertain whether a prosecution against this particular officer would succeed — even assuming that a state prosecutor could convince a jury to convict.