Torture of detainees? No. 'Coercion'? It depends.

When he signed the new terror legislation into law earlier this week, President Bush said the measure fulfilled his most important requirement – that the Central Intelligence Agency be authorized to continue using aggressive interrogation tactics against Al-Qaeda leaders and operatives.

"This program is one of the most successful intelligence efforts in American history," the president said on Tuesday. "It has helped prevent attacks on our country. And the bill I sign today will ensure that we can continue using this vital tool to protect the American people for years to come."

Despite Mr. Bush's forceful statement, legal and other experts say the new law does not give the White House – and the CIA – the clear and broad authorization the president had requested.

There is room for aggressive interrogators to maneuver, these analysts say, but no green light for such controversial interrogation methods as simulated drowning or prolonged hypothermia.

"It is a kinder, gentler version of the program," says David Rivkin, a lawyer and former official in the administrations of Presidents Reagan and George H. W. Bush. "The president got a little less than what he originally wanted, but he still got a lot."

What the president won was a congressional endorsement of the concept of using coercive interrogations – provided the techniques are not too extreme.

"This is no longer just George Bush's program," Mr. Rivkin says. "The two political branches have come together and spoken in unison on this."

The Military Commissions Act of 2006 sets rules for war crimes tribunals and establishes procedures for US interrogations of unlawful enemy combatants. In June, the Supreme Court ruled that the US must comply with the basic protections of Common Article 3 of the Geneva Conventions in its treatment of detainees in the war on terror.

The new act does this by barring US personnel from engaging in specific crimes such as torture, murder, and rape. But it also prohibits "cruel or inhuman treatment" causing "serious physical or mental pain or suffering."

It is this "cruel or inhuman" standard that creates potential legal liability for some of the harsh interrogation tactics reportedly used in the past on Al Qaeda suspects.

The CIA stopped using many of those tactics when the Detainee Treatment Act was passed in December 2005. That law included a similar provision against cruel or inhuman treatment.

This was the source of the standoff last month between the White House and three Republican senators – John McCain, John Warner, and Lindsey Graham – over interrogation standards. The Bush administration objected to the more restrictive standard, but the senators held firm.

The end result is that Bush retains some flexibility in the new law to adopt regulations authorizing certain kinds of coercive interrogation tactics – but his options aren't as wide as they might have been, analysts say.

"The law would seem to allow the CIA to use interrogation methods that don't cause serious physical or mental harm," says John Yoo, a former Justice Department official and author of a new book "War By Other Means."

Much of the debate over interrogation methods has focused on the harshest tactics, like simulated drowning, also called waterboarding, says Mr. Yoo, a law professor at the University of California at Berkeley School of Law. But interrogators can choose from a range of less extreme tactics, like the kinds of methods used during military basic training, Yoo says. The key is that tactics must not cause "serious physical or mental harm," he says.

"The law prohibits some of the extreme methods, but it doesn't prohibit all interrogation methods that go beyond questioning," he says.

In his book, Yoo draws a distinction between torture, which is outlawed, and coercive interrogation, which is not.

The import of the new law is that while torture continues to be unlawful in every instance, coercive interrogation may also sometimes rise to the level of illegality.

Yoo's main point is that in a world where a handful of terrorists can wield weapons capable of destroying an entire city, the commander in chief must have the flexibility to respond effectively to such threats.

Coercive interrogations have yielded actionable intelligence from Al Qaeda leaders and operatives, Yoo says, including alleged 9/11 mastermind Khalid Sheikh Mohammed and suspected 20th hijacker Mohammed Al-Kahtani.

Other analysts say such tactics are not necessary. "In my experience this kind of torture-like behavior on the part of the interrogator is counterproductive and any professional interrogator will tell you this," says Arthur Hulnick, who served as an Air Force intelligence officer and interrogator in South Korea and later worked for 28 years at the CIA.

"This notion that the only way you get information is by putting people in a life-threatening situation violates everything I know about how this stuff is done," says Mr. Hulnick, now a professor of international relations at Boston University. "Patience and careful questions is what does it."

Fred Hitz, a former CIA inspector general, says the White House should embrace the approach taken in the newly authorized US Army Field Manual. It includes a so-called Golden Rule test easily understood by any 18-year-old soldier, he says.

The test: If the proposed interrogation method was used by the enemy against one of your fellow soldiers, would you believe the soldier had been abused?

"That same approach has to be taken for CIA officers," says Mr. Hitz, now a professor at the University of Virginia School of Law. "Agency people don't sign up to do intelligence work so they can engage in abusive interrogations. The notion that there is a cadre of fire-breathers (at the CIA) wanting to be turned loose is just plain wrong," he said in a teleconference with reporters. "It is going to be a long time before a CIA operator steps into this gray area," he added.

Rivkin says it is unrealistic to ban coercive interrogations. He says by his reading the new law authorizes modest use of several controversial interrogation techniques, including modest use of sleep deprivation, temperature extremes, and stress positions.

•Establishes special rules for military-commission trials for Al Qaeda suspects accused of committing war crimes. The rules permit the exclusion of a defendant from his trial if classified evidence is being presented, and the admission of hearsay and coerced statements as evidence.

•Authorizes a three-officer military panel to determine a detainee's status as an enemy combatant eligible for indefinite detention in US custody. This is in lieu of the ability to file a habeas corpus petition challenging the legality of the detention in federal court.

•Creates a retroactive legal defense for US personnel who engaged in harsh interrogation tactics from September 2001 to December 2005. Also narrows the range of activities that might constitute a violation of Common Article 3 of the Geneva Conventions outlawing torture and cruel treatment.

•Expands the definition of an unlawful enemy combatant to provide that anyone who offers "material support" to someone engaged in hostilities against the US can be held indefinitely in military detention, regardless of whether he or she actually engaged in hostilities. Also provides that only noncitizens held as unlawful enemy combatants may be tried by a military commission.