Updated

Lawyers for Guantanamo detainees held more than five years without charges asked the Supreme Court Monday to step in a third time to guarantee that they can challenge their confinement in U.S. courts.

The detainees want the justices to hear their case and issue a decision before the court ends its term in early summer.

"Not only are these questions of paramount legal importance, but the extreme and worsening plight of the Guantanamo detainees make them questions of great humanitarian urgency as well," lawyers for the detainees wrote in court papers urging the justices to decide the case.

The court has twice ruled that foreigners imprisoned at the U.S. naval base in Cuba can pursue their cases in American courts, rejecting Bush administration arguments.

The latest Supreme Court appeal follows a federal appeals court ruling last month that limited detainees' legal rights. The 2-1 decision by the U.S. Court of Appeals for the D.C. Circuit upheld a key provision of the Military Commissions Act, which Bush pushed through Congress last year to set up a Defense Department system to prosecute terrorism suspects. Now, detainees must prove to three-officer military panels that they don't pose a terror threat.

Separately, the justices said they would not grant quick review in the cases of two other Guantanamo detainees who have been designated by the Pentagon to face criminal charges in front of a military tribunal.

Salim Ahmed Hamdan of Yemen and Omar Khadr, a Canadian, wanted a high court ruling before their military trials take place, possibly as early as this summer.

If the court agrees to hear the other detainee cases on a fast track, arguments could be held May 7, the detainees lawyers said. The justices could render a decision by the customary end of their term in late June.

The administration does not oppose expedited consideration of the appeals, the lawyers said.

The island prison at the U.S. Navy base on land leased from Cuba has become a rallying cry for international and domestic criticism of administration policy in the war on terror.

Some of the nearly 400 prisoners have been at Guantanamo since the detention facility opened more than five years ago — after the Sept. 11 terrorist attacks. A number of detainees have committed suicide.

The administration has argued that legal protections do not apply to foreigners outside American territory, and that the Guantanamo prison is beyond the reach of U.S. civilian courts.

Hundreds of people suspected of ties to al-Qaida and the Taliban — including some teenagers — had been swept up by the U.S. military and secretly shipped there beginning in 2002.

Many of the detainees were the innocent victims of Afghan and Pakistani bounty hunters who sold them to U.S. forces, lawyers for the detainees have said.

Democrats who took over the House and Senate in the midterm elections in November have vowed to rewrite the 2006 law that swept away the detainees' access to U.S. courts. It was enacted by the then-Republican-controlled Congress at the request of the White House.

The Supreme Court has twice thwarted the administration's efforts to keep the detainees out of the courts.

The Bush administration has reacted to each of the two previous rebuffs by undertaking remedial measures.

In 2004, the justices ruled that the courts can hear the detainees' cases, saying that prisoners under U.S. control have access to civilian courts, no matter where they are being held.

In 2006, the justices ruled that President Bush's plan for military war crimes trials, planned for a small number of Guantanamo Bay detainees, is illegal under U.S. and international law. The justices also said a law that Congress passed in 2005 to limit federal court lawsuits by Guantanamo detainees did not apply to pending cases.

After the Supreme Court ruling in 2004, the Pentagon set up panels that reviewed whether each of the detainees had been correctly categorized as an enemy combatant, and therefore not entitled to any legal rights.

After the justices' ruling in 2006, Congress at the urging of the White House enacted the law which blocked detainees from coming into U.S. courts.