The Supreme Court held Thursday that migrants do not need to be forced back to Mexico pending decisions in their U.S. immigration court cases, paving the way for the Biden administration to reverse the Trump-era policy.

In a 5-4 decision, the high court sided with the Biden administration’s authority to rescind the “Remain in Mexico” program, formally known as the Migrant Protection Protocols.

While in effect during the Trump administration, the policy required some 70,000 migrants, including asylum-seekers, who crossed the border and requested protections to wait in Mexico for final decisions in their U.S. immigration court cases.

The Biden administration tried to formally end the policy in June. But officials in Republican-led states of Texas and Missouri challenged the move, and lower courts ordered the program reinstated late last year.

The Supreme Court on Thursday reversed those lower court orders. The case now returns to a lower court to consider whether a Biden administration memo from October complied with the administrative requirements for wiping out the policy.

‘May’ return

The Supreme Court found that the administration is not legally required to return migrants to Mexico when the U.S. lacks the capacity to detain them in the country — in part because no recent administration had done so, and Congress for decades has not funded enough detention centers.

Chief Justice John G. Roberts Jr., writing for the majority, noted that a federal immigration law states that the federal government “may” return migrants to neighboring countries pending deportation proceedings.

“The statute says ‘may.’ And ‘may’ does not just suggest discretion, it ‘clearly connotes’ it,” Roberts wrote. He was joined by Justices Stephen G. Breyer, Sonia Sotomayor, Elena Kagan and Brett M. Kavanaugh.

The chief justice also stressed the foreign relations consequences to the appeals court’s interpretation otherwise, since the U.S. cannot return migrants to Mexico without that nation’s agreement.

By finding that the immigration statute mandated these returns to Mexico, the appeals court “imposed a significant burden upon the Executive’s ability to conduct diplomatic relations with Mexico,” the opinion says.

The justices also concluded that the lower courts should have considered Homeland Security Secretary Alejandro Mayorkas’ later memo, issued in October several months after it first tried to end the program, which offered further reasoning behind his decision to end the “Remain in Mexico” policy.

This memo was issued while the government’s appeal was pending, but the appeals court refused to review it. Now it will become the centerpiece of the legal fight at the lower courts.

‘Legislative stalemate’

In a concurring opinion, Kavanaugh sided with the majority fully, but added, “the larger policy story behind this case” is the “multi-decade inability of the political branches to provide DHS with sufficient facilities to detain noncitizens who seek to enter the United States pending their immigration proceedings.”

“But this Court has authority to address only the legal issues before us. We do not have authority to end the legislative stalemate or to resolve the underlying policy problems,” Kanavaugh continued.

In a dissent, Justice Samuel A. Alito Jr., joined by Justices Clarence Thomas and Neil M. Gorsuch, said the federal immigration statute does require DHS to return any migrants to Mexico it doesn’t have room to detain. They accused the majority of relying on “a blinkered method of statutory interpretation that we have firmly rejected.”

Justice Amy Coney Barrett, in a separate dissent, wrote that she agreed with the merits of the majority opinion but would have sent the case back to consider additional jurisdictional questions.

Rare victory

The high court ruling delivers a rare victory for the Biden administration, which has faced legal challenges to its efforts to undo the Trump administration’s immigration agenda at nearly every turn.

Texas Attorney General Ken Paxton said in a news release the high court’s decision was “wrongly decided.”

“Today’s decision makes the border crisis worse,” Paxton said. “But it’s not the end. I’ll keep pressing forward and focus on securing the border and keeping our communities safe in the dozen other immigration suits I’m litigating in court.”

Meanwhile, Democratic lawmakers and immigrant advocates hailed the ruling.

Judy Rabinovitz of the American Civil Liberties Union’s immigrants’ rights project called on the Biden administration to “move forward swiftly to finally terminate ‘remain in Mexico’ for good — a result that has been long, and unjustly, delayed.”

Sen. Bob Menendez, D-N.J., said he hopes Thursday’s ruling will “be the first step towards ending our federal government’s use of short-term deterrence strategies that rely on cruelty to keep asylum-seekers out of the United States.”

Rep. Raul Ruiz, D-Calif., who chairs the Congressional Hispanic Caucus, called the ruling “a step in the right direction,” but added that “work remains to build a more fair and humane asylum process.”

Previous action

The case centered on an August ruling by Judge Matthew J. Kacsmaryk of the Northern District of Texas, who ordered the Biden administration to revive the contested program after Texas and Missouri sued.

Kacsmaryk, a Trump appointee, found that the administration has not followed administrative requirements when rescinding the policy, and that the federal immigration statute mandates that migrants be returned to Mexico when detention isn’t possible.

The Biden administration revived the program in December, while continuing to fight the ruling in court. Mayorkas also issued his second memo in October, providing further reasoning for rescinding the program, including by detailing the harms to migrants waiting in Mexico.

The U.S. Court of Appeals for the 5th Circuit later upheld Kacsmaryk’s ruling and refused to consider Mayorkas’ subsequent memo.

The high court agreed to take up the case on a faster schedule, hearing oral arguments in April, just a few months after the government asked for review.