WASHINGTON -- President Bush yesterday signed into law new rules on interrogating detainees and prosecuting suspected terrorists at Guantanamo Bay, calling the measure ``one of the most important pieces of legislation in the war on terror."

But as Bush and a group of key Republican senators hailed the compromise that led to the passage of the new rules last month, the American Civil Liberties Union called it "one of the worst civil liberties measures ever enacted in American history." Groups of defense lawyers vowed to fight the new law in court, calling it "blatantly unconstitutional" because it denies detainees the right to challenge their detention in court.

The lawyers' vows assure that the battle over the treatment and prosecution of detainees -- which consumed Congress for much of September and sparked a brief Republican rebellion against the administration -- will continue in courtrooms in the coming years, almost certainly finding its way to the Supreme Court.

The law bans US agents from inflicting severe physical or mental pain and using torture during interrogations. But it gives the White House wide latitude to define what constitutes torture and "cruel treatment" under the Geneva Conventions, and it effectively grants legal amnesty to White House officials who authorized harsh techniques in the past to protect CIA agents who have reportedly used mock drownings, sleep deprivation, and hypothermia during interrogations.

The law also bars US courts from hearing any civil or criminal cases regarding a detainee's treatment while in US custody.

"This bill provides legal protections that ensure our military and intelligence personnel will not have to fear lawsuits filed by terrorists, simply for doing their jobs," Bush said, lauding the CIA interrogation program as a "vital tool" that has thwarted numerous attacks. "This program has been one of the most successful intelligence efforts in American history."

It is unclear whether the new law bans mock drownings and other such tactics. Senator John McCain of Arizona, a Republican and former Vietnam POW who spearheaded the effort to outlaw torture, said those tactics would be prohibited. But White House press secretary Tony Snow would not specify which methods would be allowed.

"The government will not tell you the precise questioning techniques, for the reasons that have been outlined many times before," he said. "You do not want to give those who are apprehended, or terrorists, the ability to plan in advance for techniques that might be used."

In an unusual move, the Bush administration broke with its practice of issuing "signing statements," which Bush has repeatedly used to assert an expansive view of his own powers as commander in chief, and to ignore statutory limits if he decides that violating a law is necessary to protect national security.

Snow had said this week that Bush would not need to issue a signing statement for this law because Congress "did a really good job" in drafting it. He joked that the White House wanted to "frustrate [the media] because everybody has been waiting for one."

In the coming weeks, Snow said, the White House will publish in the Federal Register a broad interpretation of what acts constitute torture under the Geneva Conventions.

When it comes to the government's prosecution of detainees, the law sets up a new system of military trials, after the Supreme Court struck down the old one in June. The justices ruled that the tribunals Bush authorized to try the detainees had not been approved by Congress.

Months of wrangling ensued between Bush and key Senate Republicans who wanted the White House to explicitly ban torture and put limits on the use of evidence in detainee trials if the information was collected through coercion and torture.

Critics of the new law, however, contend that it denies justice for detainees because it cuts off access to federal courts. The vast majority of the 450 detainees in Guantanamo, critics say, are not accused of terrorist acts and are unlikely to ever stand trial, and their only recourse had been to file petitions in federal court challenging their detentions.

The new law now blocks the court from hearing those petitions. Yesterday, the Department of Justice immediately sent a letter to a US appeals court in Washington announcing that the Guantanamo detainees no longer have access to the court.

Defense lawyers said they would appeal, arguing that the Constitution guarantees a detainee's right to challenge his or her detention in court, and that that right cannot be so easily denied by Congress.

"Even though that was Congress's intent, we completely don't buy the idea that you can do that," said Patrick Ehlers , a member of the Oregon public defender's office, which is representing seven Guantanamo Bay detainees. Ehlers predicted that it could take years before the Supreme Court settles the matter; in the meantime, he said, cases that his office has been working on for years would be halted and the detainees will continue to be held unjustly.

Ehlers said his office has collected witness statements from Afghanistan that he says would prove his clients' innocence in court, including videotaped testimony from an Afghan deputy minister that one client worked for on a legally recognized charity, not a terrorist group. "Just as the president is signing a bill that closes the courthouse door, here are three cases of guys in the door that say, `We're innocent,' " he said.

Democrats yesterday criticized the new law.

"The administration initially tried to establish military commissions without congressional approval, but it failed to bring any detainee to justice in the five years since 9/11 and the commissions were struck down by the Supreme Court last term," Senator Edward M. Kennedy of Massachusetts said in a statement. "The administration's new scheme is likely to suffer the same fate, and Congress will have to pass further legislation to try to get it right."

Senator Patrick J. Leahy of Vermont, a ranking member of the Judiciary Committee, said Congress cannot strip away protections enshrined in the Constitution, no matter the circumstances. "It is a sad day when the rubber-stamp Congress undercuts our freedoms," he said in a statement.

But Bush insisted that the law will help "secure this country."

"It sends a clear message," he said. "This nation is patient and decent and fair, and will never back down from the threats to our freedom."
© Copyright 2006 Globe Newspaper Company.

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