An executive summary of the long-awaited Senate Intelligence Committee torture report was finally released to the public on Tuesday, after nearly two years of political fighting over how much of it would see the light of day — read it here. The report, written by the Senate Intelligence Committee's Democratic staff, examines the CIA's use of torture during the Bush administration: what specifically happened, and what the results were.

The release, held up for months by the Obama administration, casts the CIA in a terrible light, not just for what they did but how they sold the public on it. The report says the CIA misled the public, Congress, even the White House. "The interrogations of CIA detainees were brutal and far worse than the CIA represented to policymakers and others," the report says. But possibly the most significant conclusion of the report is that torture was simply not effective at foiling terror attacks.

Here's what you need to know about the torture report, its long journey to partial release today, and what it means for America's past use of — and continued debate around — torture.

The roots of America's torture debate

Shortly after 9/11, as the US sought to gain intelligence that could halt further attacks, the CIA began using what it called "enhanced interrogation" of captured terrorist suspects held in "black sites." The six painful techniques they used were waterboarding, keeping a prisoner naked in a cold cell and dousing him with cold water, forcing the prisoner to stand shackled for hours on end (often including sleep deprivation), shaking the prisoner, and two types of slaps to the prisoner.

Three of the six techniques were initially used by the Bush administration but later banned; the remainder were banned by President Obama when he took office. In addition, the CIA sometimes used various other violent or coercive techniques that weren't officially authorized.

A debate over torture's effectiveness at producing useful intelligence has been going on for years

This program caused a tremendous political controversy when it was revealed, with many Democrats and some Republicans, such as Sen. John McCain, criticized the Bush Administration for authorizing torture.

But many Bush administration and intelligence officials argued that these techniques were necessary to yield intelligence that was used to halt terror attacks. "The enhanced interrogation techniques were absolutely essential in saving thousands of American lives and preventing further attacks against the United States, and giving us the intelligence we needed to go find Al Qaeda," former Vice President Dick Cheney said in 2009.

Still, others with access to classified information said otherwise. For instance, FBI Director Robert Mueller said in 2008 that he wasn't aware of any planned attack in America that had been foiled because of enhanced interrogation.

A large body of evidence, supported by independent research as well as statements from many former interrogators, suggests that torture is not a reliable source of intelligence information. Still, the disagreement among former government officials — as well as the somewhat muddier politics of the issue — have helped keep the debate over torture's effectiveness going for years.

In response, in March 2009, the Senate Intelligence Committee announced it would attempt to answer the controversy with a new major review. Its purpose was to assess exactly what the CIA did, and particularly to evaluate whether torture techniques led detainees to reveal information that stopped terrorist attacks — whether it "worked." The report was not intended to result in prosecutions or to assign blame to particular agency or administration officials.

How investigators judged American torture programs

The report is based on investigators' review of over six million pages of CIA documents, from contemporary notes by lower-level officials to higher-level memos.

Only the report's executive summary is being released

Initially, the bipartisan investigators planned to interview CIA employees as well. But in August 2009, the Justice Department launched its own investigation of the CIA over torture. Senate Intelligence Committee Republicans argued that CIA employees would now be put at legal risk by answering investigators' questions, so the committee's GOP members dropped out of the effort entirely. (The Justice Department's investigation concluded in 2012 without any charges being brought.)

The remaining (Democratic) investigators responded by deciding to limit their report solely to the documents rather than conducting new interviews. The final report says it's based on "CIA operational cables, reports, memoranda, intelligence products, and numerous interviews conducted of CIA personnel by various entities within the CIA."

The CIA agreed that Senate Intelligence Committee staffers could examine the agency's internal cables — but only at a special, secure facility, using special computers, after the CIA's own outside contractors had already reviewed the documents. As a result, the review reportedly cost $40 million before its first draft was completed in December 2012.

Since then, the Intelligence Committee has been battling with the administration over how much information in the report's 600-page executive summary can be released to the public. The thousands of pages of the report beyond that summary will remain classified, and many details of the executive summary will be redacted.

What the report found: torture wasn't effective and the CIA misled the public

According to several reports by journalists clued into the report's findings early, the Senate investigators concluded that torture wasn't effective and that CIA officials had misled the government and the public into believing that torture produced valuable information.

The report finds that enhanced interrogation didn't result in any important intelligence breakthroughs, according to the Washington Post's Adam Goldman, Greg Miller, and Ellen Nakashima — and, furthermore, that CIA officials have repeatedly misrepresented the facts to argue that torture did in fact work. One detainee in particular, Abu Zubaida, revealed useful information when he was questioned under normal circumstances by an FBI agent. Yet the CIA took credit for that intelligence, told other government bodies it had been obtained through coercive interrogation, and used it to argue the program was effective, according to the report.

At the New York Times, Matt Apuzzo, Haeyoun Park, and Larry Buchanan run down eight examples where the CIA claimed its tactics led to the prevention of attacks or capture of terrorists, but the report argues otherwise.

The report also describes several cases of abuse, including some that were not publicly known, in great detail. It reveals, for example, the case of a detainee known as Ammar al-Baluchi. According the Post's summary of the report, "CIA interrogators forcibly kept his head under the water while he struggled to breathe and beat him repeatedly, hitting him with a truncheon-like object and smashing his head against a wall."

According to Mark Hosenball and Jeff Mason of Reuters, the report also reveals that detainee Abdel Rahman al Nashiri was threatened with a buzzing power drill, and that another detainee "was sexually threatened with a broomstick."

"At least five CIA detainees were subjected to 'rectal rehydration' or rectal feeding without documented medical necessity," the report states. It adds that officers "threatened at least three detainees with harm to their families," including a threat to sexually abuse the mother of one detainee, and to harm the children of another.

The report also found that the CIA held more detainees than the public had previously known — at least 119 in total — and that the agency sometimes knew "very little" about certain detainees it was holding. At least 39 of these detainees were subjected to enhanced interrogation techniques. Also, the report says the CIA itself determined that 26 of the 119 detainees didn't meet the standard for detention, and so were wrongfully held.

Why the report is so controversial: the politics of torture are still contentious

There are several somewhat-related controversies around the report and Tuesday's release of its executive summary.



First, several CIA officials have for months been privately disputing the conclusions and criticizing the Senate staffers involved, and the agency has now publicly weighed in disagreeing with several aspects of the report. According to the Post, CIA officials say the study is "marred by factual errors and misguided conclusions." Former CIA Deputy Director John McConnell told Politico's Josh Gerstein that the report was "a warped, dishonest piece of work."

The CIA sent an official response to the committee last year which you can read here. CIA director John Brennan released a statement Tuesday disputing some of the committee's conclusions as well, saying, "Our review indicates that interrogations of detainees on whom EITs were used did produce intelligence that helped thwart attack plans, capture terrorists, and save lives."

Bush administration officials, including the former president himself, have also been defending the CIA's actions in recent days. "These are patriots and whatever the report says, if it diminishes their contributions to our country, it is way off base," Bush said this Sunday.

Second, the very process of researching the report was mired in controversy. While Senate staffers were reviewing various documents at the secure facility, the CIA accessed the hard drives of the computers they were using, to see what the staffers had found. The CIA also removed access to certain documents — violating their earlier agreement. Senator Feinstein issued a scathing denunciation on the Senate floor; the CIA's inspector general eventually admitted that the agency had "improperly accessed" those hard drives. (You can read more details about that here.)

Finally, in recent days some Republicans have alleged that the release of the report could lead to attacks on American troops and personnel. "Our foreign partners are telling us this will cause violence and deaths," House Intelligence Committee Chairman Mike Rogers claimed this Sunday. Bloomberg View's Josh Rogin reported that Secretary of State John Kerry has privately argued against releasing the summary soon, arguing that now wasn't a good time. CIA officials have also worried that the report's information could lead to the identities of some of their employees being exposed, as Shane Harris and Kimberly Dozier report.

Overall, the release of the report's executive summary will shed more light on this dark chapter of America's recent history. But, despite the report's strongly-worded findings that torture was ineffective, the pushback from Republicans and former intelligence officials shows that there won't be a political consensus anytime soon that "enhanced interrogation" was a mistake.

Update: This article has been updated to reflect the report's findings.