It describes how people with suspected terrorist ties were captured, sent to secret detention sites around the world, and subjected to techniques that included torture.
It concludes the program was not only cruel, but also ineffective and incompetently managed. It says details were hidden from top government officials — including then-president George W. Bush.
Here are highlights from a 500-page executive summary of the landmark 6,800-page report, which took years to produce and has not been fully released.
— Many people were wrongfully detained. The CIA held at least 119 prisoners, 26 of them wrongfully. One was an "intellectually challenged" man, captured in the hope his relatives might start talking. Four detainees were actually moles for national intelligence agencies. A complete list of detainees might never be available, because the CIA never compiled one.
— Torture didn't help stop terrorism. Of the 39 prisoners or more who were subjected to the CIA's so-called enhanced interrogation, some offered faulty intelligence, some offered nothing at all, and some had already co-operated before they were harmed. The report looked at 20 supposed cases where the CIA claimed it gained valuable intelligence from this type of questioning, and found the claim exaggerated or untrue in every case. This finding was challenged in a minority report where some Senate Republicans accused the authors of a bias, and listed several attacks that might have been thwarted.
— It was more brutal than the CIA let on. Detainees were slapped, slammed into walls, and subjected to sleep deprivation for up to 180 hours. Waterboarding caused convulsions, vomiting and near-drowning. Detainees were subjected to forced nudity and "rectal feeding." Psychological torture included threats to rape a detainee's mother, slit one's mother's throat, and hurt prisoners' children.
— The prison conditions were worse than the CIA said. One detainee died in 2002 of suspected hypothermia. Inmates were held in dark rooms, subjected to loud noise and provided buckets to excrete in.
— Even President Bush was kept in the dark. Bush didn't receive a briefing on the CIA's enhanced-interrogation techniques for four years — until 2006. The CIA also misled the White House, Congress and the public about how useful the program was. When Bush finally received a briefing he expressed concern about the "image of a detainee, chained to the ceiling, clothed in a diaper, and forced to go to the bathroom on himself."
— The White House didn't necessarily push for disclosure. Key details of the program were withheld from the secretaries of state and defence, Colin Powell and Donald Rumsfeld. An internal CIA email from 2003 said the White House was "extremely concerned Powell would blow his stack if he were briefed on what's going on."
— The Department of Justice produced an opinion for the White House on the legality of the program, based on bad information from the CIA.
— The CIA didn't even keep a list. It couldn't say exactly how many were detained. For example, it told the report authors it had fewer than 100 prisoners, and less than one-third of them were subjected to "enhanced interrogation." But in searching written documents, the authors found references to at least 119 detainees — with at least 39 of them subjected to those methods.
— The CIA fought congressional attempts to learn about the program. For several years, it refused to answer questions, provide details, or gave inaccurate information when elected lawmakers requested information.
— The program sidelined other parts of the U.S. government — including those with expertise in national security. The FBI and foreign-intelligence experts at the State Department were kept at bay. In two countries, U.S. ambassadors were only informed of plans to set up a detention site once an agreement had been reached, and in two others, the CIA told local governments not to inform the U.S. ambassador.
— The CIA avoided oversight by its own inspector-general. It did not brief the internal inspector on the program until after a detainee died, and then provided inaccurate information.
— The CIA leaked classified details to the media — much of it inaccurate, designed to exaggerate the success of the program.
— The program was poorly set up and poorly managed. For example, in December 2003, CIA personnel reported that they had made the "unsettling discovery" that the CIA had been holding a number of detainees about whom the CIA knew "very little" at multiple detention sites in a certain country.
— Private contractors profited. By 2005, the CIA outsourced interrogations to two psychologists — who had military experience, but no background in counterterrorism, specialized knowledge of al-Qaida, or the Arabic language and culture. The base contract was for $180 million, including a legal-liability fund.
— Internal concerns about the program within the CIA were marginalized and ignored. CIA officers, interrogators, psychologists, and medical staff expressed concerns about the practices, to no avail.
— The CIA rarely reprimanded or held personnel accountable for inappropriate behaviour.
— The chain of command broke down. At least 17 detainees were subjected to CIA enhanced interrogation techniques without authorization from headquarters.
— The system collapsed under its own weight. By 2006, foreign governments resisted hosting these facilities, and information about them regularly appeared in the media. There were at least 113 people detained in 2004, only six more in 2004, four in 2005, one in 2006, one in 2007 and none since April 2008.
— The program damaged U.S. standing in the world. Diplomatic relations suffered. And the U.S. wound up providing millions of dollars to government officials in some countries to host these facilities — in cash payments.
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