As more details emerge from detainees sent by the United States to countries that allegedly engage in torture, the CIA is under growing pressure to account for some of its top-secret actions in the war on terror - especially its interrogation techniques.
The controversy is leading to a rare moral debate about the methods and effectiveness of some of the agency's most shadowy ways of extracting information.
Historically, the public has known relatively little about such back-room techniques. But because so many details have already surfaced - from the exposure of the Abu Ghraib prison abuses to more recent investigations into the use of torture at Guantánamo Bay and other sites - the CIA is under growing criticism from lawmakers and human rights groups to clarify and justify its interrogation policies.
The criticism is particularly acute over the practice of rendition - nabbing and transporting suspected terrorists to other countries, some of which are believed to employ brutal practices that would be illegal in the US to elicit information.
"We need to ask the question of how the [rendition] program was originally conceived and what it is now," says Karen Greenberg, director of the Center for Law and Security at New York University.
At the core of the controversy is whether the CIA has the authority to use other countries in interrogations, whether the practice violates international law, and whether information obtained in this way is credible anyway.
The practice was first authorized by President Reagan in 1986 to deal with terrorists who might have been responsible for the 1983 bombing of the US Marine barracks in Beirut, experts say. It was again put into use by the Clinton administration to transport terrorists and drug lords to the US or other countries for prosecution.
After 9/11, President Bush reportedly broadened the CIA's authority to use renditions, and as a result, experts say, the agency has sent 100 to 150 people from one country to another for interrogation. They've done this, experts say, without legal hearings and without granting the International Committee of the Red Cross access to the detainees, a right afforded military prisoners under the Geneva Conventions.
Some, such as Khaled Sheikh Mohammed and Abu Zubaydah, high-level Al Qaeda operatives, continue to be held in "undisclosed locations." But the detainees have provided invaluable information about Al Qaeda's plans and capabilities, according to government officials and members of the 9/11 Commission. Still, at least three have been released and claim to have been sent to countries where they were tortured.
• Khaled al-Masri, a Lebanese-born German, asserts he was pulled from a bus on the Serbia-Macedonia border in December 2003. He says he was sent to Afghanistan, where he was beaten and drugged. After five months, he was released without being charged. German authorities have stated that al-Masri's story checks out.
• Maher Arar, a Syrian-born Canadian, was detained at an airport in New York two weeks after the 9/11 attacks. He was sent to Syria, where he says he was beaten. He was released a year later.
• Mamdouh Habib, an Egyptian-born Australian, was arrested in Pakistan several weeks after the 9/11 attacks. He was moved to Egypt, Afghanistan, and later to Camp Delta at Guantánamo. He says he was beaten and subjected to electric shocks during detention. He was released after 40 months without being charged.
Though the program remains shrouded in secrecy, lawmakers have tried to glean information from CIA Director Porter Goss. At a March 17 hearing, for instance, Sen. John McCain (R) of Arizona asked the director if there had been sufficient training and specific guidelines for those carrying out the interrogations.
"I believe that there is policy, and I believe that it is very well understood at this point," Goss responded.
"Well, some of those policies at one time were to make the prisoners feel that they were drowning," Senator McCain replied.
Goss continued: "You're getting into, again, an area of what I will call professional interrogation techniques, and I would like...."
McCain interrupted: "That's the area that I'm concerned about, because I'm not sure that the interrogators are fully aware of ... what they can and cannot do when interrogating a prisoner."
More is known, however, about past practices because the former head of the CIA's Osama bin Laden unit has spoken out in defense of them. Michael Scheuer, who wrote two books about the government's war on terror under "Anonymous," says the rendition program expanded under his watch, when Al Qaeda's intentions to target the US became clear.
He estimates that between late 1995 and 1999 the CIA carried out some two dozen renditions. The most common method: CIA operatives would identify a suspected terrorist and get foreign intelligence agents or police to make the arrest. The CIA would then transport the person to a third country - usually Egypt - where either an arrest warrant had been issued or the person had already been convicted of a crime "in absentia."
The goals, says Mr. Scheuer, were to take the person who had either participated in a terror attack or who was planning one off the street and to grab as much evidence - written and electronic - as possible. "Once those two goals were accomplished, the mission was a success," Scheuer says. "We never counted on interrogations producing anything.... The information you'd get from any interrogation would be of limited use."
In fact, he says they learned far more from the materials seized during the raids. "We saw things they didn't expect us to see," Scheuer says. "The information they had entered electronically, particularly, was entered without the expectation that anyone outside the organization would see it."
Although Scheuer says he's not allowed to talk about specific cases, he does cite several arrests in his first book, "Through Our Enemies' Eyes." In one instance, he says that an Al Qaeda cell in Albania was successfully broken up by arresting and sending four suspected operatives to Egypt.
In general, Scheuer says that although they obtained assurances that the Egyptians wouldn't torture suspects, he thought they might, and says they never followed up because Egypt was a sovereign country.
"The goal of the program was to protect Americans, and that seems to get lost in the shuffle," he says.
From here, the controversy over the program is only likely to grow. The CIA's Inspector General (IG) is investigating several instances in which torture allegedly took place during some of these interrogations. At least two Senate oversight committees are waiting for the IG's report and pushing for more accountability from CIA leaders. Moreover, three foreign countries - Italy, Sweden, and Germany - are investigating possible CIA abductions of people in their countries.
On the legal issue, a recent report issued by the New York University School of Law together with the Association of the Bar of the City of New York found that rendition is an "illegal practice under both domestic and international law." It said the US is "duty bound" to cease all such acts.