For all the recent headlines about migrant caravans advancing toward our southern border, the problem of sanctuary cities is already here.

Increasingly, our highest courts are serving as the battleground in this fight.

The Supreme Court has agreed to rule on Nielsen v. Preap, a case on appeal from the Ninth Circuit, which will decide this question: Does a noncitizen released from criminal custody become exempt from mandatory detention under U.S. immigration law if, after the noncitizen is released from criminal custody, the Department of Homeland Security (DHS) does not take the noncitizen into immigration custody immediately?

That statute specifically states that “the attorney general may take into custody any alien [who is inadmissible or deportable as a result of having committed one or more crimes] when the alien is released, without regard to whether the alien is released on parole, supervised release, or probation, and without regard to whether the alien may be arrested or imprisoned again for the same offense” (emphasis added).

In settling this issue, the court needs to take the dangerous impact of sanctuary cities into consideration.

And Americans who still have not grasped the seriousness of the issue ought to realize that if state and local government can ignore one federal law, what would stop them from ignoring another in the future, and perhaps one that sanctuarists strongly support?

The three named plaintiffs are legal permanent residents (or LPRs; informally, green card holders). They served their prison sentences but years later were taken into immigration custody without bond.

They argue that they are not subject to mandatory detention because they were not detained when released from criminal custody (Preap v. Johnson). Their reading of the word “when” in the statute, with which the Ninth Circuit agreed, is that it means “at the point,” therefore excluding the specific LPRs in question.

The government, however, argued that “when” is a duty-triggering clause, not a time-limiting clause, and therefore means “at any point after which.”

At stake before the Supreme Court is whether detainees would then be placed in removal, or deportation, proceedings automatically — or would be entitled to a bail hearing, whereby they could be released, potentially, back into society.

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The court heard oral arguments on October 10. The petitioners’ (government) attorney, Zachary Tripp, explained that even though there is no mandated time limit, the government’s desire is to detain the violators in question as quickly as possible: “We need to arrest the next day, the next month, when it happens, [but] sometimes it many not occur for years. Because DHS doesn’t know where the person is.”

Significant changes to immigration law were established via the Immigration and Nationality Act of 1952, the Immigration Act of 1990, and the Illegal Immigration Reform and Immigrant Responsibility Act of 1996 (IIRAIRA). Significantly, on those laws’ respective enactment dates, the most recent one being 22 years ago, the notion of sanctuary cities was hardly a factor in the overall immigration phenomenon — and certainly not a prevalent one.

But in 2018, numerous large cities in the United States (and the state of California) have openly and proudly declared themselves to be sanctuary cities. That is, not only would they grant full rights to those here illegally living within their provinces equal to anyone (legal immigrants, legal nonimmigrants, and natural-born U.S. citizens) residing in their cities, but they would refuse to share with the federal government the immigration status of noncitizens convicted of crimes and therefore subject to deportation.

When Cecillia Wang, attorney for the respondents, pointed out that in IRRAIRA Congress identified measures so that state and local governments would cooperate with U.S. immigration authorities regarding sharing information with them, in what was arguably the most poignant question during oral arguments, Justice Samuel Alito asked her, in turn, “And is that happening now?”

Wang’s response, tellingly, failed to point out the obvious: If states and cities do not initiate the process by proactively informing the federal government about immigration law violators, how would the latter even know that such persons exist, so as to request custody of them upon the completion of their prison sentences?

It is truly a sad day in America when some state and local governments openly defy federal law, thus directly violating the Constitution’s supremacy clause (Article VI, Clause 2).

Although the question to be decided in Nielsen is whether the word “when” is duty-triggering or time-limiting, the more compelling issue to consider is how can the United States continue to function as a society of laws if state and local governments openly disregard them?

It is truly a sad day in America when some state and local governments openly defy federal law, thus directly violating the Constitution’s supremacy clause.

Consider this: Slavery was abolished in the United States a long, long time ago, and subsequent federal laws continue to declare slavery a crime, just as the various crimes and/or civil wrongs about immigration are federal.

Yet what if sanctuary city mayors instead established slave cities, in which slavery would be practiced, and the local authorities would refuse to share information about practicing slaveholders with the federal government, which was interested in putting an end to such outrageous and illegal behavior?

Related: ICE Official in New Jersey Blames Sanctuary Prison for Three Deaths

Would sanctuary city advocates be just as nonchalant if there were slave cities instead?

Has our society of laws been reduced to selective enforcement based on one’s own subjective sense of values or whims?

Constantinos E. Scaros has practiced, taught, and written about immigration law. His latest book is “Stop Calling Them ‘Immigrants,’” available in print and Kindle formats. He is a contributing writer for Attorneys United for a Secure America.

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