The memos include highly classified guidance given to the Central Intelligence Agency in 2002 by Justice Department official Jay Bybee, and three issued to the agency in 2005 that expanded the parameters of the interrogation program. The names of CIA case officers and agency officials who participated in the interrogations were blacked out, a concession, government officials said, to the national security officers who acted in good faith. Other redactions seem to include the details of other intelligence community collection programs and the names of some detainees.

Two senior administration officials said that the Department did not intend to rule out prosecuting officials who failed to act in accordance with the OLC guidelines.

The memos make clear that the Bush administration relied on a fairly simple principle: the believed that the methods used by the interrogators did not cause intense or severe or lasting physical pain, did not meet the threshold for torture, and did not violate the law. 

There are many revelations and details buried in  the banal, technical language of lawyers: 

Among the revelations:

 ** Through 2005, the CIA used "enhanced interrogation techniques" on 28 of 94 so-called "high value detainees."

 ** Waterboarding was theoretically allowed only in cases where the information solicited from the prisoner could thwart an imminent terrorist attack; the Justice Department permitted only "six applications of water lasting more than ten seconds" for every two-hour period during which a detainee was strapped to the board. Only 12 minutes of water torture was allowed per 24-hour period. Also: the CIA put potential waterboardees on a fluid diet before the torture in order to prevent them from choking to death on food that might be stuck in the GI tract.

 ** The OLC concluded that the CIA's careful application of the program didn't "shock the conscience" of a reasonable person and thus would not trigger a statute that would leave interrogators vulnerable to prosecution

 ** The name of at least one High Value Detainee who was subject to "enhanced techniques" has been redacted. Later, however, the same memo mentions a "Gul" who was subjected to enhanced techniques. This appears to be an inadvertent omission.  

 ** Through 2005, the CIA said that only 3 detainees were subject to 96-hour sleep deprivation

 ** See page 7 of this document for an example of a "typical" interrogation: abdominal slaps, facial holds, "walling," wall-standing. 

** The 2002 memo  contended it was legal to place an insect in a cramped confined space with a prisoner, provided that the insect was not poisonous. The CIA wanted to use this technique on Abu Zubaydah, who was afraid of poisonous insects. Nowhere is Zubaydah's degraded mental state mentioned.

 ** It sanctioned techniques which caused less pain than then type of pain one would experience with a major injury

 ** It allowed a previously disclosed technique called "walling," involving the slamming of a detainee's head back against a fake wall.

** It presumed that the CIA interrogators did not want to cause Zubaydah "severe" mental or physical pain;

 ** The CIA justified its techniques by referring to the SERE program, which teachers soldiers how to avoid capture and interrogation.

 ** A May 10, 2005 memo calls torture "abhorrent"

Before the memos were released, the administration circulated them to members of Congress who had been critical of the Bush administration's approach.  A few minutes after Air Force One landed in Mexico, Obama said in a statement that the techniques described in the memos "undermine our moral authority and do not make us safer."

He said their extraordinary nature compelled their release. But, in a juxtaposition that will rankle many of his civil libertarian allies, he then defended his administration's court arguments favoring the executive branch's right to protect classified information.

"While I believe strongly in transparency and accountability, I also believe that in a dangerous world, the United States must sometimes carry out intelligence operations and protect information that is classified for purposes of national security. I have already fought for that principle in court and will do so again in the future."

Obama said that the memos release should assure "those who carried out their duties relying in good faith upon legal advice from the Department of Justice that they will not be subject to prosecution."

Eric Holder, the attorney general, echoed Obama's message. "At a time of great challenges and disturbing disunity, nothing will be gained by spending our time and energy laying blame for the past."

Administration officials said that Obama had relied on Holder's advice about the ill-wisdom of future prosecutions, but it is nonetheless unusual for a president to declare, independently, that certain practices or people are immune from prosecution because to do so would cause consternation in the land.  As chief law enforcement officer, Holder would, in theory, have had to make that determination himself.  The decision to announce immunity for officials was made on Wednesday, officials said, after a protracted internal debate that involved more than a dozen key officials. 

Sen. Patrick Leahy (D-VT), the chairman of the Judiciary Committee, said that the memos' content "is as alarming as I feared it would be."  Breaking with the administration's expressed desire to move along, he repeated his call for a "Truth Commission" that would  "take a thorough accounting of what happened, not to move a partisan agenda, but to own up to what was done in the name of national security, and to learn from it.  This is another step in that direction."

Sen. Carl Levin, the chairman of the Armed Services Committee,  praised the president's decision to release the memos. "If we are to retain our status as a leader in the world, we must acknowledge and confront these abuses.  Only then can we credibly object to the use of abusive tactics on our troops when they are captured  "The President's decision to release these four memos will contribute to our national security by bringing us closer to these goals," he said.

Sen. Sheldon Whitehouse, a member of the Judiciary and Intelligence committees who has endorsed the Truth Commission concept, said he agreed with Holder that those officers who acted in "good faith" should not be prosecuted. He said that senior Justice Department officials who might be found guilty of misconduct should be disciplined by other means. The Justice Department's Office of Professional Responsibility is slated to release a report evaluating the lawyers and their conduct.