Federal judges in D.C. pressed the Biden administration Thursday about safeguards for prisoners in Guantánamo Bay, Cuba, seeking to challenge their detention, even as the court seemed reluctant to find that the suspected terrorists who remain there have due process rights under the U.S. Constitution.

The case before the court of a Yemeni man held without charge or trial for nearly 20 years drew renewed attention to the military prison and comes one month after President Biden ended the war in Afghanistan.

The Biden administration has backed away from the Trump-era position that Guantánamo inmates have no such rights. Instead, Justice Department lawyers urged the court to rule narrowly and avoid deciding a constitutional question that has remained unanswered for decades.

Three of the last four presidents, including Biden, have said the facility should close. Its population has dwindled from more than 700 detainees to 39, and most who remain have never been charged.

A full complement of 11 judges on the influential U.S. Court of Appeals for the D.C. Circuit reviewed the case of Abdulsalam al-Hela, a Yemeni businessman held at Guantánamo since 2004. His lawyers say Hela’s “seemingly endless detention” is “punitive and unjustifiable,” and they are urging the court to release him immediately.

The Justice Department told the court that Hela, 50, has had a “meaningful opportunity” to challenge the basis for his detention and that the process already includes “robust” protections for detainees. The department has warned that a broad holding by the court extending due process rights to Guantánamo detainees could adversely impact military, intelligence and law enforcement operations.

Several judges asked Thursday whether there was still a controversy for the court to resolve because Hela was recently approved for transfer out of Guantánamo — and they asked how the end of the Afghanistan war affected his continued detention.

“You don’t deny that circumstances have changed dramatically?” Judge Judith Rogers asked Justice Department lawyer Sarah Harrington.

Circumstances have changed, Harrington answered, but Biden and his military leaders have “made clear that conflict with al-Qaeda and associated forces” continues and Hela’s detention remains lawful.

Judge Ketanji Brown Jackson asked whether the government takes the position that it can still hold Hela “indefinitely” after a review board in June cleared him for relocation to another country.

Even if the judges were to order Hela’s release, Harrington said the court cannot insert itself in military and diplomatic negotiations over the transfer of a detainee. Such a ruling would be “just be words on a paper,” Harrington said. “I don’t think it would have any effect” in part because of the challenge of relocating detainees.

Still, she emphasized that the government has “no intention of holding him any longer than we’d like to,” she said. “It’s complex and we are working on it.”

That was of little comfort to Hela’s lawyer David Zionts, who told the court that the government’s assurance still amounted to “indefinite detention.”

Several judges, including Jackson and Robert L. Wilkins, also expressed concern about the current system that allows the government to share certain classified evidence against a detainee only with the presiding judge, and not the detainee’s lawyer.

But it was unclear from the more than two hours of argument whether the court could address those concerns about detainees’ rights without answering the broader constitutional question.

Several hours after the argument ended, the government took the unusual step of filing a letter with the court to clear up any mistaken impression from the hearing that there were ever times when evidence was so highly sensitive that it would also be withheld from the judge.

“To clarify any confusion, in this matter, the answer is no,” Harrington wrote to the court. “No such information was withheld from the district judge.”

While Biden wants to shut the prison, he has not laid out a detailed plan for doing so, a likely indication of the lack of palatable options available to him and the abiding Republican opposition to closure.

So far, the Biden administration has repatriated one prisoner to Morocco, and officials are hoping to resettle at least another 10 overseas. A review board designated al-Hela as eligible for transfer to a country that can put in place “appropriate security measures.”

Another dozen inmates are at some stage of a military trial process widely seen as dysfunctional. Twenty years after 9/11, the case of five men accused in the attacks remains in pretrial proceedings. Some earlier convictions were overturned.

The Supreme Court next week will take up the case of Guantánamo terrorism suspect Abu Zubaida, who was captured after the 9/11 attacks and is requesting more information about his CIA-sponsored torture.

It’s unclear how the United States’ departure from Afghanistan may impact deliberations over Guantánamo’s future. Though some lawmakers have called for repealing the 2001 wartime authorization that Congress passed after 9/11, which successive administrations have cited as a basis for detaining suspects there and for other counterterrorism activities, they have not yet done so.

In recent months, congressional Democrats have called on the administration to revisit the government’s legal position on detainees’ rights.

“Our nation has failed to provide due process to detainees held at Guantánamo, resulting in the use of unreliable hearsay and coerced or torture-derived evidence and a shamefully low burden of proof for depriving men of their liberty,” Sen. Richard J. Durbin (D-Ill.), who chairs the Senate Judiciary Committee, wrote in a letter this summer to Attorney General Merrick Garland.

The Supreme Court in 2008 ruled that noncitizen detainees at the prison have the right, known as habeas corpus, to go to court to challenge their detention. But human rights advocates and lawyers for detainees say the current system is unbalanced, lacks the traditional protections for defendants, and makes it impossible for detainees to prevail regardless of the strength of the government’s case.

Under the current habeas process, the government can withhold certain classified evidence from a detainee and his lawyers, including information obtained in counterterrorism raids. If the Constitution’s due process clause applies, detainees like Hela will have greater access to the evidence against them and the government will face a higher bar for proving its case in court.

The Biden administration is “fighting in court to continue to hold somebody that it has decided it doesn’t want to continue to hold in a prison the president has said he wants to close,” said Wells Dixon of the Center for Constitutional Rights, which filed a brief on behalf of Hela and represents other detainees. “It makes no sense except to illustrate a failure of policy on the part of the Biden administration.”

The full D.C. Circuit agreed to revisit the case after a three-judge panel of the court sided with the Trump administration in finding there is no right to due process for Guantánamo prisoners. A district court judge previously found that Hela likely provided “substantial support” to two groups associated with al-Qaeda and that he probably helped extremists travel with fake passports.

The full appeals court could decide to send Hela’s case back to District Court with new standards for additional review.

Hela’s lawyers say he was a “respected citizen of high character” who had no connection to any terrorist organization. After being seized by Egyptian officials in Cairo, Hela was turned over to the CIA and held in secret overseas prisons, where he was tortured, according to court documents.

He “has never been charged or convicted of a crime. Yet he has suffered life-crushing, punitive detention at the hands of the U.S. for nearly two decades,” Hela’s lawyers said in court filings.