Updated

The Supreme Court's rebuff of the Bush administration's Guantanamo military tribunals knocks the issue into the halls of Congress, where GOP leaders are already trying to figure out how to give the president the options he wants for dealing with suspected terror detainees.

That way forward could be long and difficult. Congress will negotiate a highly technical legal road — one fraught with political implications in an election year — under the scrutiny of the international community that has condemned the continued use of the Guantanamo prison.

The ruling does little to clear up the immediate future of the 450 prisoners inside the razor wire at the Guantanamo Bay Naval Base, Cuba, since most have never been charged with crimes and may never go to trial.

Within hours of the high court's ruling that the military tribunals were illegal under U.S. and international law, President Bush said he would work with Congress to fix the problem. Still, Bush vowed that the result "won't cause killers to be put out on the street."

Congress' options include everything from legalizing the administration's proposed military tribunals to using the U.S. court system or enacting laws that, as Justice John Paul Stevens recommended, use military courts-martial as a template.

Stevens, writing for the court in the 5-3 ruling, said the Bush administration lacked the authority to take the "extraordinary measure" of scheduling special military trials for inmates, in which defendants have fewer legal protections than in civilian U.S. courts.

Nothing in the ruling suggests shutting down the facility or challenges Bush's authority to detain enemy combatants.

Senate Majority Leader Bill Frist, R-Tenn., said he would introduce legislation after the July 4 recess that would authorize military commissions and appropriate due process procedures. Senate Judiciary Committee Chairman Arlen Specter, R-Pa., introduced a bill Thursday that did essentially that.

"To keep America safe in the war on terror, I believe we should try terrorists only before military commissions, not in our civilian courts," Frist said.

The court ruling focused on Salim Ahmed Hamdan, a one-time driver for Osama bin Laden who has spent four years at Guantanamo Bay. He faces a single count of conspiring to commit terrorism.

Lt. Cmdr. Charles Swift, Hamdan's Navy lawyer, said he told the Yemeni about the ruling by telephone. "I think he was awe-struck that the court would rule for him, and give a little man like him an equal chance. Where he's from, that is not true," Swift said.

Human rights groups endorsed proposals to use the courts-martial proceedings, saying it is a fairer proceeding. But military officials say changing the procedures to mimic courts-martial — which are largely similar to U.S. court proceedings — would bring problems.

Katherine Newell Bierman, counterterrorism counsel at Human Rights Watch, said courts-martial provide the basic fair trial guarantees that are lacking in the proposed military tribunals.

In the tribunals, she said, the accused have less access to the evidence against them, particularly if it is considered classified. Courts-martial, she said, have rules about how to deal with classified evidence, and they also have more stringent rules about prohibiting evidence that was acquired unlawfully, such as through duress or forced confessions.

Curt Goering, deputy executive director of Amnesty International, said any new rules should specify that evidence obtained under pressure should not be admissible.

"In light of the long years people have spent there, and the physical and mental abuses that have been perpetrated, and the legal limbo they've been subjected to for so long, they should really scrupulously respect international standards that have been developed for trials," he said.

Military officials, however, has said that using courts-martial could handcuff their ability to prosecute suspected terrorists because of the need to protect classified information.

The high court's ruling was viewed as a broad rebuke of the Bush administration's aggressive efforts to root out and jail enemy combatants in the war on terror.

But it may, as another alternative to the trials, accelerate efforts to transfer or release more of the detainees — many of whom have been there for more than three years.

Of the 450 detainees being held, 10 have been charged with crimes and four more have had charges prepared against them but were never formally charged or arraigned.

Another 99 detainees have been deemed eligible for transfer to their home countries and 16 have been found eligible for release. They could be shipped out of the facility as soon as the U.S. negotiates transfers or releases with their home countries.

A key impediment to the transfers, however, is the concern that the detainees might be tortured or killed once they reach their homeland.

The U.S. began using the Guantanamo Bay Naval Base in eastern Cuba in January 2002 to hold people suspected of links to Al Qaeda or the Taliban.

As many as 759 people have been held over the years at Guantanamo, according to Defense Department documents released to The Associated Press in response to a Freedom of Information Act lawsuit. Of those, 218 have been Afghans, the largest group, and 136 have been Saudis.

The ruling came on the court's final day before summer break, and Chief Justice John Roberts was sidelined in the case because as an appeals court judge he had backed the government in this case last year. That ruling was overturned Thursday