This post has been updated.

Over the objections of the CIA, the Senate Intelligence Committee on Tuesday released the findings of a long-awaited report on the CIA’s Detention and Interrogation Program, in which it subjected detainees to practices widely criticized as torture — what it called “enhanced interrogation techniques.” The agency has argued that even if the tactics were harsh, they were necessary. They helped to track down Osama bin Laden, the agency said, and the CIA even helped to underscore that idea by consulting on the Hollywood blockbuster Zero Dark Thirty.

The exhaustive Senate report — the executive summary alone runs 500 pages — found that the program instead violated “U.S. law, treaty obligations, and our values.” It was ineffective, the report found, and in some cases detrimental to national security, a fact the CIA worked to conceal from government agencies, the White House, lawmakers and the public. And it didn’t help to find bin Laden.

The CIA, in a response posted to its website, acknowledged “shortcomings” in its interrogation program, and said that the agency had made “mistakes.” But it maintained that the program had been effective and that the CIA hadn’t “systematically and intentionally misled” officials or the public.

The bulk of the Senate report’s information was gathered from the CIA’s own internal documents. Read the executive summary of the report here. We’ve outlined the most significant findings below.

Interrogations “were brutal and far worse” than the CIA let on

The report details numerous examples of harsh interrogation practices by the CIA, some previously reported, others new. At least five detainees were subjected to “rectal rehydration,” or rectal feeding without medical necessity. Detainees were slapped, slammed against walls and in some instances, exposed to sleep deprivation for up to seven-and-a-half days. Some were stuffed into coffin-sized boxes, and even threatened with death.

“One interrogator told another detainee that he would never go to court, because ‘we can never let the world know what I have done to you,'” according to the report.

The report also suggests that more prisoners may have been subjected to waterboarding — a practice that simulates the sensation of drowning — than the three cases previously acknowledged by the CIA. The waterboarding of Abu Zubaydah, the report notes, led him to become “completely unresponsive, with bubbles rising through his open, full mouth.” Zubaydah was waterboarded 83 times and kept in crammed boxes for nearly 300 hours.

The number of detainees was larger than initially known

CIA leadership told officials that 98 prisoners were in its detention program, but agency records show that at least 119 were actually held, according to the report. Of that number, “39 were subjected to the CIA’s enhanced interrogation techniques,” while at least 26 others “were wrongfully held.” Wrongfully held detainees included:

An “intellectually challenged” man whose CIA detention was used solely as leverage to get a family member to provide information, two individuals who were intelligence sources for foreign liaison services and were former CIA sources, and two individuals whom the CIA assessed to be connected to Al Qaeda based solely on information fabricated by a CIA detainee subjected to the CIA’s enhanced interrogation techniques.

The CIA exposed detainees to unauthorized interrogation practices

Before 2004, the CIA subjected detainees to nudity, “dietary manipulation,” abdominal slapping and cold water dousing, even though neither technique had been approved by the Department of Justice. At least 17 detainees were put through enhanced interrogation without the approval of CIA headquarters, while “multiple detainees were subjected to techniques that were applied in ways that diverged from the specific authorization, or were subjected to enhanced interrogation techniques by interrogators who had not been authorized to use them.”

“Enhanced interrogation techniques” didn’t work — not even to find bin Laden.

The CIA’s harshest interrogation methods didn’t help the agency gain valuable intelligence or gain the cooperation of detainees, the Senate report found.

Instead, many detainees offered false information under duress, providing fake leads that the CIA nevertheless chased down as high priorities. Seven of the 39 CIA detainees exposed to enhanced interrogation produced “no intelligence” while in CIA custody. In one instance, the CIA held an Afghan national in solitary confinement for one month because he had the same name as someone they believed was targeting U.S. military bases.

Plots the CIA claimed they “disrupted” were never in the works. Even the accurate intelligence the CIA received came from detainees before they were subjected to torture, the report found.

That includes Hassan Ghul, who provided the key intelligence that led American officials to Osama bin Laden — the knowledge that the Al Qaeda leader was likely in Peshawar in Pakistan, and that he had a courier named Abu Ahmad al-Kuwaiti.

When Ghul was handed over to the CIA, he wasn’t tortured at first. “He sang like a tweetie bird,” said one CIA official familiar with the initial interrogations. “He opened up right away and was cooperative from the outset.”

During this time, Ghul also offered accurate information on other top Al Qaeda operatives — their locations, movements, operational security and training, the report said.

After two days, Ghul was transferred to Detention Site Black. He was “shaved and barbered, stripped, and placed in the standing position against the wall,” with “his hands above his head.”

His interrogators asked for permission to use enhanced interrogation techniques. The request was approved by CIA headquarters that day.

Ghul was subjected to 59 hours of sleep deprivation, which caused hallucinations. Although medical personnel were supposed to intervene and allow detainees to sleep once they began hallucinating, that didn’t always happen.

A CIA doctor reported that Ghul suffered from “notable physiological fatigue,” “Abdominal and back muscle pain/spasm,” “mild paralysis of arms, legs and feet [that] are secondary to his hanging position and extreme degree of sleep deprivation.”

He was told that the pain would stop when it was confirmed that he was telling the truth. Throughout all, Ghul repeated some of what he’d said initially, but offered no other useful information.

On two separate occasions, in 2005 and 2011, the CIA would tell other government officials that Ghul had provided actionable intelligence after being subjected to enhanced interrogation techniques. Ghul was ultimately released.

The program hampered legitimate national security investigations

At the same time, the CIA program made it more difficult for the FBI, the State Department and the Office of the Director of National Intelligence to address national security matters, the report found.

The CIA held back important information from these agencies, kept them from speaking with detainees and lied about the extent of the program, the report found. When the head of the FBI, Robert Mueller, sought to interrogate CIA detainees to follow up on reports of threats to the U.S., those requests were denied.

In most cases, the CIA also didn’t tell the State Department about so-called foreign “black sites” where it housed detainees, or where they were, even though the host countries “generally” knew. In two countries, the CIA told local government officials not to tell the U.S. ambassadors about a deal to host black sites in their countries.

The CIA knew the program was faulty, but quelled internal dissent

Years earlier, the report found, agency officials testified before Congress that “inhumane physical or psychological techniques are counterproductive because they do not produce intelligence and will probably result in false answers.”

Even so, the agency never conducted an analysis of how effective its enhanced interrogation techniques were, despite recommendations by the agency’s own inspector general, and requests by the Senate Intelligence Committee and the national security adviser, the report found.

Instead, the CIA conducted internal assessments by people who developed and ran the program. “There are no CIA records to indicate that any of the reviews independently validated the ‘effectiveness’ claims presented by the CIA,” the report found. The agency didn’t even confirm its own basic assertion that it had acquired useful information from the detainees.

There was plenty of internal criticism, including from CIA officers who questioned how effective the methods were and spoke out against them, and recommendations from psychologists and the CIA Office of Medical Services. Those concerns were ignored — and at times officers were asked not to put their complaints in writing.

The CIA concealed or shared inaccurate information with the White House, the National Security Council and other government agencies

The report found that the CIA prevented proper oversight of its interrogation program by providing “extensive amounts of inaccurate and incomplete information” on the “operation and effectiveness” of its enhanced interrogation methods to officials at the White House and National Security Council.

When Director of Central Intelligence George Tenet and CIA General Counsel Scott Muller met with Vice President Dick Cheney, National Security Adviser Condoleezza Rice and others in July 2003, they made the case that 50 percent of the CIA’s intelligence reports on Al Qaeda came from detainees, and warned that the “termination of this program will result in loss of life, possibly extensive.”

The report also reviewed 20 examples that the CIA held up as counterterrorism successes attributed to the use of enhanced interrogation methods and “found them to be wrong in fundamental respects.”

The secretaries of defense and state were not briefed on the program until September 2003, and an internal CIA email from July 2003 noted that “the [White House] is extremely concerned [Secretary of State Colin] Powell would blow his stack if he were to be briefed on what’s been going on.”

The summary states that the CIA “consistently omitted” the intelligence gained from sources other than detainees who underwent enhanced interrogation, “leaving the false impression the CIA was acquiring unique information from the use of the techniques.”

Based on the CIA’s own records, President George W. Bush wasn’t briefed on specific interrogation techniques until April 2006.

When Bush finally was briefed, he expressed discomfort at the “image of a detainee, chained to the ceiling, clothed in a diaper, and forced to go to the bathroom on himself,” according to CIA records cited by the committee.

The report also included an appendix detailing discrepancies between internal CIA records and the testimony of former CIA Director Michael Hayden before the Senate Intelligence Committee.

In 2007, for example, Hayden asserted about Zubaydah that, “We knew he knew a lot. He would not talk. We were going nowhere with him.”

However, the report concluded that more intelligence reports were gathered during the first two months of Zubaydah’s interrogation, before the CIA waterboarded him, than the two months during and after he was put through the practice.

According to the report, the discrepancies in Hayden’s 2007 testimony involved the scope of the use of enhanced interrogation, its effectiveness in producing useful intelligence, screening and training processes for interrogators and dissent within the ranks, among other issues.

Memos from the Department of Justice’s Office of Legal Counsel relied on “inaccurate information” from the CIA

The CIA presented “inaccurate” information to the Department of Justice’s Office of Legal Counsel (OLC), which wrote several memos from 2002 to 2007 providing legal justification for the program. In particular, the CIA misrepresented:

• The conditions under which detainees were kept.
• The use of enhanced interrogation.
• The physical impact of those techniques on the detainees.
• The effectiveness of those techniques

For example, when the OLC issued its “Standards of Conduct for Interrogation,” or what has come to be known as the “torture memo” in 2002, the memo relied on information provided by the CIA about Abu Zubaydah’s status and role in Al Qaeda, his resistance to questioning and his withholding of information on future plots. The committee’s report concludes that much of that information was “unsupported by CIA records.”

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