Will Congress come up with a Deferred Action for Childhood Arrivals (DACA) fix? Can President Trump defend his travel ban by throwing North Korea, Chad and Venezuela onto the list of countries? Can the administration punish so-called sanctuary cities that don’t respond to requests to detain suspected illegal immigrants absent a warrant? However consequential these issues may be, they pale in comparison with two cases before the Supreme Court that could remake the immigration debate.

The first, Sessions v. Dimaya, heard yesterday, raises the question of whether authorities can use the definition “crime of violence” to expel a burglar whose crime involved no violence. What seems like a straightforward statutory test actually raises a more fundamental issue as to the vagueness of immigration statutes. Scotusblog reports:

In language that [the late Justice] Scalia would have loved, [Justice Neil] Gorsuch noted that the due process clause does not include the criminal/civil distinction embraced by the government: “I look at the text of the Constitution, always a good place to start, and the Due Process Clause speaks of the loss of life, liberty, or property. It doesn’t draw a civil/criminal line, and yet, elsewhere, even in the Fifth Amendment, I do see that line drawn, the right of self-incrimination, for example.”
On the defensive throughout, [Deputy Solicitor General Edwin] Kneedler emphasized that the federal government traditionally has enjoyed broad discretion in the enforcement of the immigration laws.

To the Scotusblog lawyers, it seemed “Dimaya has a fair chance of prevailing in the Supreme Court [with] Gorsuch, the possible deciding vote in the case. … Gorsuch had ready responses to line-drawing and other problems that might arise if the [statute failed the] vagueness doctrine.”

This might have wide-ranging implications. If the court is going to tighten up standards on immigration law for terms such as “crime of violence,” wait until the court gets to “sanctuary city,” which is defined nowhere in law or regulation. The president and Congress may have discretion in the immigration arena, but as we learned in the travel ban cases, that discretion is not unlimited. The courts get the last say.

The second immigration case, Jennings v. Rodriguez, was heard today. The issue in that case is whether “the Constitution requires that aliens seeking admission to the United States who are subject to mandatory detention … must be afforded bond hearings, with the possibility of release into the United States, if detention lasts six months.” The long detention of immigrants (some permanent residents) awaiting deportation, in some cases for years, has long been a source of concern for civil liberties groups, many of which filed friend-of-the-court briefs. The lawyers representing individuals in this case — all held at least six months — argued that the due process clause prohibits prolonged incarceration without an individualized hearing. In their brief, they noted that thousands of individuals are held beyond six months, one year on average, and hundreds for more than two years.

Here, too, the government looked as though it might not prevail. Reuters reports: “A majority of the justices appeared sympathetic to the idea that immigrants held long-term should be eligible for a hearing that would let them argue for their release. But the court’s conservatives seemed skeptical over whether such a hearing should be triggered automatically after six months, as a lower court had ruled.” The administration may complain that a ruling would require a “dramatic and wholesale revision” of the manner of detaining and releasing immigrants, but frankly, that should be of no concern to the court if it determines, as immigration advocates have argued for years, that this practice constitutes a massive and widespread infringement of constitutional rights. In a press release put out after the hearing, the ACLU argued, “Forcing people to languish indefinitely in detention without a hearing as they make their case to remain in the U.S. is cruel and unnecessary. We’re hopeful the Supreme Court, which has long held that the right to a hearing is a bedrock due process requirement, will agree.” It pointed out, “The rights at stake in this case are as critical as ever given the Trump administration’s pledge to lock up even more people as part of its crackdown on immigrant communities.”

In short, while the White House and Congress are in the hands of a GOP largely antagonistic toward immigrants and anxious to deport as many as possible with as little delay as possible, our checks and balances make the courts the ultimate backstop. Immigrant rights and civil liberties groups in the Trump era are going to have to be litigiously bold if they want to mitigate the worst of the administration’s practices. Over the past 24 hours, we got just a taste of what that might look like.