In a pair of immigration law opinions today, the Supreme Court made things harder for noncitizens indefinitely detained by immigration authorities.

In one, decided almost unanimously and written by Justice Sonia Sotomayor, the court ended the existing requirement that such people get hearings after six months of detention to see if they could be released on bond into the US. In the other, decided 6-3 over a sharp partial dissent from Sotomayor, the justices held that detainees lack the legal authority to challenge the circumstances of their confinement through a class-action suit. Together, the opinions signal that the Supreme Court is less sympathetic to detention conditions than the lower courts.

The six-month reviews that the court ended do not appear expressly in federal immigration law statutes or regulations. The lower courts created them, using reasoning derived from a 2001 Supreme Court precedent that says the Constitution bars detention beyond six months of noncitizens who are on the way to being sent out of the country for having committed serious crimes.

The relevant statute says that, ordinarily, if someone has been deemed “removable” from the US  because of being here illegally, the government may detain that person for 90 days. But it also provides the option of longer detention – it doesn’t say how long – for some people.

Among them are those who entered the country illegally or violated their immigration status while here. (The statute also allows longer detention of people who have committed certain crimes or who might be a danger to national security or the community.)

The petitioner in the first of today’s cases, Antonio Arteaga-Martinez, is a citizen of Mexico who was kicked out of the U.S. in 2012 and then soon returned without authorization. In 2018, when he had been living in the US for six years, he was arrested and detained pending being sent home. Arteaga-Martinez then filed an asylum claim, stating that he feared persecution or torture in Mexico. An asylum officer found the claim reasonable and referred him to an immigration judge to verify the claim. While awaiting that proceeding, Arteaga-Martinez remained in indefinite detention.

While detained, Arteaga-Martinez asked for a six-month bond hearing. If, at the hearing, he was deemed eligible for bond, he would have been able to stay in the US, free from detention, while he waited to see if his asylum claim was granted.

The lower courts said yes to his request. They had created that kind of bond hearing by saying the statute must be understood to require it. Although the statute doesn’t mention a hearing, and on its face allows indefinite confinement, the lower courts were hoping to avoid the problem of unconstitutional indefinite detention.

Writing for the majority, Sotomayor said the statute can’t be read as requiring a six-month hearing that appears nowhere in its language. That put an end to the hearings. Her opinion left open the possibility that detainees like Arteaga-Martinez could go back to the lower courts and claim that indefinite detention would be unconstitutional.

They might win such a claim, in which case some kind of hearing — probably a six-month hearing — could be reinstated on the theory that it is required by the Constitution. Justice Stephen Breyer wrote a separate opinion saying that logically, the lower courts should do exactly that.

Of course, Sotomayor’s hinted sympathy to such a constitutional claim might not extend to the other justices. That much was clear from the second immigration opinion.

In this case, Mexican citizens detained under the same legal provision as Arteaga-Martinez went to court on behalf of all other similarly situated detainees asking for a clear ruling that they were entitled by statute to a six-month bond hearing.

Justice Samuel Alito, joined by the court’s other conservatives, said that a different federal immigration statute barred the detainees’ lawsuit altogether. That statute says the lower federal courts may not “enjoin or restrain” the operation of a number of provisions of federal immigration law except in reference to an “individual alien.” According to Alito, the law prohibits the kind of general order that would emerge from a class-action suit brought on behalf of all detainees, not just one of them.

Sotomayor, joined by the court’s two other liberals, dissented, denouncing Alito’s opinion as a “blinkered” decision that would “leave many vulnerable noncitizens unable to protect their rights.” The reason she was so concerned is that the consequences go well beyond the six-month hearing issue. The Alito decision bars essentially all class actions by immigration detainees.

As Sotomayor explained, detainees aren’t entitled to lawyers. They are isolated and cut off. They are archetypal examples of people who need class actions to defend their legal rights.

What is supposed to happen next is that detainees get the chance to argue to the lower courts that the Constitution requires a six-month bond hearing. Now, because of the Alito opinion, that claim will have to be made by an individual, not in a class action. The Alito opinion suggests, without saying so, that the court’s conservatives may not be very sympathetic when the case returns to them.

More on the Supreme Court From Bloomberg Opinion:

• US Justices Are Looking More Like Politicians: Noah Feldman

• Supreme Court Has a Nasty Surprise in Store for Business: Noah Feldman 

• Supreme Court’s Leak Investigation Is Self-Destructive: Stephen L. Carter

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Noah Feldman is a Bloomberg Opinion columnist. A professor of law at Harvard University, he is author, most recently, of “The Broken Constitution: Lincoln, Slavery and the Refounding of America.”

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