The Biden administration urged the Supreme Court on Tuesday to revive guidelines narrowing enforcement priorities for immigration agents, arguing the Department of Homeland Security doesn’t receive enough funding from Congress to operate without them.

At an oral argument that lasted more than two hours, the justices grappled with several legal issues surrounding a challenge to guidance signed by Homeland Security Secretary Alejandro Mayorkas meant to focus the department’s limited resources.

But the questions often veered into what to do with a lower court order that struck down the guidelines, finding they conflict with parts of the immigration statute and illegally substitute the administration’s preferences for those required by law.

Solicitor General Elizabeth Prelogar told the justices that “across 25 years and five presidential administrations,” DHS has never interpreted the law to require all immigrants to be detained and couldn’t comply with a ruling ordering such action.

“Given congressional funding choices, it would be impossible for DHS to do so,” Prelogar said.

Texas and Louisiana, which challenged the immigration guidelines, argue that the government is required to arrest and detain tens of thousands of immigrants under an immigration provision that states the government “shall take into custody” several categories of immigrants, including those with certain criminal convictions.

Congress has historically not given the department enough funding to detain all those individuals. In fiscal 2022, Congress gave the department enough funding for just 34,000 adult detention beds.

Judd Stone, solicitor general for Texas who argued for the state challengers, told the justices that it was “at least disputable that it’s not possible to detain everyone.”

But Stone also conceded that there are as many as 80,000 immigrants who would be required to be detained under the states’ interpretation of the law — tens of thousands more people than could have been detained at any one time even under peak detention levels during the Trump administration.

Justice Brett M. Kavanaugh appeared somewhat moved by the concern that any ruling couldn’t be enforced.

“If you prevail here, what will happen?” Kavanaugh asked Stone. “That’s a concern, because I’m not sure how much will change because they don’t have the resources to change.”

Congressional intent

The justices appeared split on the core issue in the case, whether the guidance itself violated federal immigration law, as they muddled through thorny areas of immigration law governing detention.

Before the court is the question of whether the immigration statute’s use of the word “shall” should be read as a mandate, or as a “may” that preserves prosecutorial discretion.

Prelogar argued that if the high court were to find that “shall” is a mandate throughout the federal immigration statute, leaving Congress to pick up the pieces, it “would be incredibly destabilizing” in the meantime.

Chief Justice John G. Roberts Jr. said it was a “compelling argument” that Congress would not have intended this result when it drafted the immigration statute.

But the chief justice also questioned whether that concern should even be taken into consideration.

“It’s our job to say what the law is, not whether it can be possibly implemented or whether or not there are difficulties there, and I don’t think we should change that responsibility,” Roberts said.

Procedural hurdles

The justices, who will issue a decision before the end of the term at the end of June, spent the bulk of Tuesday’s oral arguments on procedural issues, including whether the states could file the legal challenge in the first place and whether the Texas federal judge could strike it down.

The majority of justices, including those from both ideological wings, took issue with Prelogar’s contention that the Texas federal court lacked the authority to terminate the guidance through a type of order known as vacatur.

Roberts said this position, which would limit the ability of lower courts to strike down agency policies they deem illegal, is “fairly radical.” He said that at the U.S. Court of Appeals for the District of Columbia Circuit, his former post, judges would vacate policies “five times before breakfast.”

Kavanaugh also called it a “pretty extreme” piece of the argument, and Justice Ketanji Brown Jackson said she had a “conceptual problem” with the government’s position.

Roberts also seemed unpersuaded by the federal government’s argument that the states do not have the right to bring their lawsuit.

Texas and Louisiana have contended they can file the challenge because the states would incur costs by having to house undocumented immigrants who may have otherwise been detained by the federal government under the enforcement guidelines.

Roberts pointed to the high court ruling earlier this year in a case over the so-called Remain in Mexico policy. The states in that case challenged the Biden administration’s attempt to rescind the Trump-era border policy, and the court found the federal government had the authority to terminate the policy.

“I thought you’d have a little more concern about an opinion of ours that’s four months old. It’s not even out of the cradle yet, and you’re throwing it under the bus,” Roberts said to Prelogar.

Still, Justice Elena Kagan warned if the high court were to conclude the states can challenge the immigration guidance based on indirect costs from immigration, it would leave most federal policies open to legal challenges.

“Do you think that there’s any immigration policy that you could not challenge under the way you view standing?” Kagan asked Stone. “We’re just going to be in a situation where every administration is confronted by suits by states that can bring a policy to a dead halt, to a dead stop, by just showing a dollar’s worth of costs?”

Kavanaugh also raised that concern, asking Stone why, under his argument, states could not challenge a presidential declaration of war based on costs incurred.