by Steve Vladeck, Professor of Law, University of Texas School of Law

The so-called “entry fiction,” pursuant to which “arriving aliens” stopped at the border are treated, for at least some constitutional purposes, as if they are not actually on U.S. soil, has been a point of controversy in judicial doctrine and legal scholarship for generations—and remains so today. But the one point on which there has been common cause has been its inapplicability to individuals living in the United States—regardless of how they got here or their current immigration status. Indeed, the Supreme Court has so held in an unbroken line of cases stretching back to the 1880s, since a contrary reading would suggest that undocumented immigrants could be tried without due process; could be subjected to cruel and unusual punishment; and so on.

Among other things, these decisions, from Yick Wo v. Hopkins to Wong Wing v. United States to Mathews v. Diaz to Plyler v. Doe, have provided important if implicit bulwarks against a true nativist turn in constitutional law. Even during periods of heightened anti-immigrant sentiment, they have generally prevented the political branches from singling out undocumented immigrants for anything other than deportation. And if undocumented immigrants cannot be singled out for especially restrictive measures, it follows a fortiori that those with lawful immigration status cannot be, either.

But at the Supreme Court’s Conference earlier today, one of the appeals it was deciding whether to hear involves a direct assault on these precedents—and on the rights of undocumented immigrants living within the United States. Indeed, I fear it is no exaggeration to suggest that, if the justices leave the lower court’s ruling intact, it could open the door to a far more aggressive—and alarming—nativist turn in immigration enforcement on the home front.

The dispute in Castro v. U.S. Dep’t of Homeland Security arises from the 1996 immigration reform laws, which created a new category of “expedited removal” for individuals stopped at the border without proper documents. To give teeth to the “expedited” part of expedited removal, Congress provided for very limited judicial review in such cases—review that, among other things, does not allow for the judicial consideration of asylum claims such as those pressed by many of those caught up in the 2014 Central American migrant crisis, including the petitioners in Castro. And although courts initially construed these restrictions narrowly to not preclude access to writs of habeas corpus, Congress in 2005 narrowed their habeas authority in such cases, as well.

In Castro, 28 women (and their minor children) who made it into the United States before being arrested and placed in expedited removal proceedings argued that they were legally entitled to asylum (and, thus, to not being removed from the country). Because the 1996 immigration laws, as interpreted by the Justice Department and as amended in 2005, deprived them of the right to even press that claim in court, they argued that these laws violated the right to judicial review of their detention guaranteed by the Constitution’s Suspension Clause.

The Supreme Court has only meaningfully interpreted the Suspension Clause once—in its 2008 ruling in Boumediene v. Bush, in which it held that the clause “has full effect” at Guantánamo Bay, and so the non-citizen terrorism suspects detained there were entitled to seek judicial review of their detention. As Justice Kennedy wrote for the Court, whether the Suspension Clause should apply to a particular class of detainees turns on three factors: “(1) the citizenship and status of the detainee and the adequacy of the process through which that status determination was made; (2) the nature of the sites where apprehension and then detention took place; and (3) the practical obstacles inherent in resolving the prisoner’s entitlement to the writ.” Even though the detainees in Boumediene were non-citizen terrorism suspects who had never set foot on U.S. soil, were captured overseas, and were held outside the United States at Guantánamo, the Supreme Court still held that these factors supported application of the Suspension Clause.

Non-citizens arrested and detained within the United States, then, should have been a much easier case. But the Philadelphia-based Third Circuit disagreed. As Judge D. Brooks Smith wrote for the majority, “[T]he Supreme Court has unequivocally concluded that ‘an alien seeking initial admission to the United States requests a privilege and has no constitutional rights regarding his application.’” That statement is true so far as it goes, but neglects the two crucial reasons why it does not lead to the conclusion that the Suspension Clause does not apply:

First, it utterly misses the point of Boumediene, which held that the Suspension Clause applies even to non-citizens who might enjoy no other constitutional protections. As Justice Kennedy explained for the Court, even when a detainee has no constitutional objection to his detention, “the Suspension Clause remains applicable and the writ relevant.” After all, as the Guantánamo litigation has repeatedly demonstrated, there are a number of ways in which government detention may be unlawful without being unconstitutional. And because Congress has forsworn judicial review in such cases, the Suspension Clause is the first, last and only check on arbitrary decision making by the political branches—and, as such, an indispensable part of the separation of powers. The court of appeals meekly suggested that Boumediene’s factors “provide little guidance” for non-citizens within the United States because “the Court derived the factors from its extraterritoriality jurisprudence in order to assess the reach of the Suspension Clause to a territory where the United States is not sovereign.” But that is exactly the point; where individuals are arrested and detained on territory over which the United States is sovereign, none of the arguments against applying the Suspension Clause hold water, because there is no structural or practical impediment to meaningful judicial review.

Second, and perhaps more importantly, the Third Circuit’s logic also obliterates the distinction the Supreme Court has drawn for over 130 years—between arriving aliens stopped at the border and non-citizens who are able, whether lawfully or otherwise, to enter the United States. In the process, the Castro decision creates a dangerous precedent for insulating a growing swath of government activity on domestic soil, and not just at the border, from judicial review—so long as it is directed at non-citizens without lawful immigration status. Reasonable minds can surely disagree about whether the migrants at issue in Castro should ultimately receive asylum; what Boumediene teaches is that the Constitution mandates that courts—and not just executive branch officials—be allowed to answer that question.

As the Trump administration pursues increasingly aggressive and legally unprecedented enforcement actions against various classes of non-citizens within the United States, that is a message the Supreme Court can, and should, reiterate, by granting certiorari in Castro and reversing. If, instead, it leaves the Court of Appeals’ decision intact, then that will provide only further incentive to the political branches to pursue increasingly restrictive (if not punitive) measures against undocumented immigrants—measures that, however pernicious, the courts would be unable to invalidate under the Third Circuit’s deeply myopic logic.