Factbox: U.S. Senate panel's findings on CIA torture

The following are some of the main findings:

* The use of "enhanced interrogation" was ineffective and never produced intelligence that helped to foil an imminent threat. The CIA's 20 most frequently cited examples of successes are wrong in many details and information gained played little or no role in the counter terrorism success. In fact, prisoners regularly lied and provided false information that deceived the CIA.

* The CIA was far more brutal than policymakers were told. The first CIA detainee, Abu Zubaydah, and many others were subjected to coercive interrogation in near non-stop fashion for days or weeks at a time. Zubaydah's interrogation was allowed to take precedence over his medical care, resulting in the infection and deterioration of a bullet wound he sustained on capture. At one point during waterboarding he became "completely unresponsive with bubbles rising through his open full mouth," the report said. The waterboarding of Khalid Sheikh Mohammed, the suspected mastermind of the Sept. 11, 2001 attacks, evolved into a "series of near drownings," it said.

* The CIA inaccurately described the conditions under which some prisoners were held, denying they resembled those at Abu Ghraib prison in Iraq. In fact, detainees at one location were kept in complete darkness and constantly shackled in isolated cells with loud noise or music and only a bucket for human waste. Lack of heat at one facility likely contributed to the death of a detainee. Some prisoners were walked around naked with their hands shackled above their heads, while others sometimes were hooded while naked and dragged down corridors while being slapped and punched. Prisoners later exhibited psychological problems, including hallucinations, paranoia and attempts at self-injury.

* The CIA provided inaccurate information about the program and its effectiveness to policymakers, including the White House, Congress and the Justice Department. After being briefed, several lawmakers objected. Senator John McCain, who was tortured as a Vietnam war prisoner, told the CIA he believed waterboarding and sleep deprivation were torture. Other senators also objected in writing. But the CIA, while seeking to use the techniques against prisoners, told the Justice Department no senators had objected.

(Compiled by David Alexander; Editing by Grant McCool)