Eighth Circuit Judge on State Enforcement of Immigration Law

Access to legal immigration, which allowed my grandparents to settle here following World War II, has been a lasting gift for my family. The welcome mat we offer to those who come here legally, however, means little if skipping the line results in the same (or even better) treatment. Now, as the federal government tries to enforce the nation’s immigration laws, Iowa wants to help. If it can do so without getting in the way, I would let it.

[I.] Let’s be clear about what happened here. Two people, plus an organization purporting to speak for two others, set out to defend the federal government from Iowa’s alleged overreach. The problem, in their view, was that Iowa made it a crime for aliens to set foot in the state if they had ever been “excluded, deported, or removed from the United States.” The remedy was what the federal government had already decided to do once before: make them leave the country. In short, it mandated self-deportation.

The parties have diametrically opposed views of what the law does: Iowa sees it as a helping hand; the plaintiffs as encroaching on federal authority. The federal government, for its part, dropped its own parallel challenge in a companion case. And it has given us assurances that, as far as it is concerned, Iowa’s efforts actually “further the purposes of federal immigration law.”

Despite these developments, the plaintiffs won a preliminary injunction. Not just any injunction, but one that appears to prohibit enforcement of the law against anyone. Fortunately, the panel sent that part back. But we should have reversed the rest too, because the overbroad injunction was far from the only problem with this case….

[III, joined by Judge James Loken.] … “A facial challenge is really just a claim that the law … at issue is unconstitutional in all its applications.” To describe them as “hard to win” would be an understatement. They are “the ‘most difficult challenge[s] to mount successfully'” because the existence of “some” constitutional applications defeats them.

The hill is even steeper than it looks. It requires proof of a negative: “no set of circumstances … under which [Iowa’s statute] would be valid.” “In effect, [the plaintiffs must] speak[] for a range of people,” from green-card-holding waiver recipients to “revolving[-]door” recidivists and violent drug traffickers. A preliminary injunction only becomes an option if the plaintiffs are “likely” to show that every application, including each of those, is unconstitutional….

Not all are, because the most obvious application is also the most obviously constitutional: the state prosecution of an individual who has committed the crime of illegal reentry under federal and state law. Both, after all, prohibit identical conduct: reentry by aliens who “ha[ve] been denied admission, excluded, deported, or removed or ha[ve] departed the United States while an order of exclusion, deportation, or removal is outstanding.” If no federal exception applies, then it is possible to comply with each, and a state prosecution does not “stand[] as an obstacle to the accomplishment and execution of the full purposes and objectives of Congress.” To the contrary, it furthers it.

Indeed, this sort of criminal-law “overlap,” a feature of federalism “[f]rom the beginning,” would “not even begin” to support preemption. Preemption could occur if state officials pursue charges against aliens who are under no federal obligation to leave the country. But given that federal and state interests align in “at least some” cases, the only type of challenge that can work is an as-applied one. Case-by-case adjudication then becomes the mechanism for defining the limits of state power.

Or at least that is how the system is supposed to work.By completely ruling out Iowa’s “parallel scheme of enforcement,” the panel opinion short-circuits this process. It purports to apply conflict preemption, but in truth it applies a Frankensteinian hybrid: something it calls “conflict preemption” but that more closely resembles field preemption. Only field preemption, after all, can block “parallel” and “complementary state regulation.”

The panel’s patchwork analysis even confused the plaintiffs, who now try to defend the decision on field-preemption grounds. The problem, of course, is that the application of field preemption is hard to square with Arizona, which allowed the state to enforce one immigration statute but not others. The one that survived required state officers to try “to determine the immigration status” of anyone they lawfully stopped and suspected of being an illegal alien. If the federal government occupied the entire field of “immigration policy” or “entry and removal,” then this provision should have been preempted. And it would have spared the Supreme Court the trouble of addressing the other Arizona provisions individually, including those that turned out to be conflict preempted.

Even as to those, the Supreme Court’s analysis does not support what the panel did here. The Court reviewed one that made it a crime for illegal aliens to “solicit … or perform work,” which “Congress [had] made a deliberate choice not to” criminalize. Another let state officers arrest aliens they suspected of a removal-triggering “public offense,” which was “greater authority” than Congress gave “trained federal immigration officers.” Unlike both of those, Iowa’s statute is nearly a mirror image of federal law, meaning that any conflict will quite literally be the exception, not the rule.

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I doubt federally approved prosecutions are the only constitutional application. I cannot imagine, for example, that an order returning an illegal reentrant “to the foreign nation from which [he or she] entered” conflicts when federal authorities have already made the same call. To the extent other circumstances pose a greater risk of conflict, “those are details relevant to an as-applied challenge, not a facial one.” All we need to know is that the existence of “some” constitutional applications is enough to foreclose a facial challenge to Iowa’s illegal-reentry law.

[IV.] Entertaining non-justiciable controversies and ignoring constitutional applications of state laws is bad enough under normal circumstances. But making these kinds of mistakes here handcuffs government officials who are trying to enforce the nation’s immigration laws. When federal officers are the ones doing it, some courts have claimed overreach. See, e.g., Vasquez Perdomo v. Noem (C.D. Cal.), stayed by 146 S. Ct. 1 (Sept. 8, 2025). When they decide to bring in backup, the government needs to check all the right boxes first. See Trump v. Illinois (U.S. 2025) (refusing to stay “a temporary restraining order barring the federalization and deployment of the [National] Guard in Illinois”). And now, if states step up to fill the void, the panel opinion sends the message that it is not their job.

Who is left to deal with “the admission and exclusion of foreign nationals …[,] a fundamental sovereign attribute” that is supposed to be “exercised by the Government’s political departments largely immune from judicial control”? Trump v. Hawaii (2018); see Fong Yue Ting v. United States (1893) (recognizing that the authority “to exclude or to expel … aliens” is the “inherent and inalienable right of every sovereign and independent nation”). More and more, the answer seems to be nobody. Not the federal government, not the states, nor anyone else.

We have a duty to rehear “questions of exceptional importance” en banc, particularly when a panel’s resolution of them “conflicts with … decision[s] of the United States Supreme Court.” This one is about as important as it gets. See Arizona (“Immigration policy shapes the destiny of the Nation.”).