On the condition of anonymity, Senate officials tell reporters that the intelligence committee plans to probe the CIA’s detainee program. The Associated Press reports that the review will take six months to a year.

Attorney General Eric Holder releases four of the Bush administration’s legal opinions sanctioning “enhanced interrogation.” Obama says he will not prosecute the CIA employees who acted on the Justice Department’s orders and “nothing will be gained by spending our time and energy laying blame for the past.”

Feinstein asks Obama to “withhold judgment” on CIA prosecutions until the committee review is finished. “This study is now underway, and I estimate its completion within the next six to eight months,” she writes to the president. “A study of the first two detainees has already been completed and will shortly be before the committee.”

The same day, then-CNN White House correspondent Ed Henry tells “Lou Dobbs Tonight” the report should take six to eight months to complete, but “obviously a lot of people [are] looking for it to happen a little bit quicker since this has been going on for a long time.”

Obama suggests he might be open to prosecutions.

“With respect to those who formulated those legal decisions, I would say that is going to be more of a decision for the Attorney General within the parameters of various laws and I don’t want to prejudge that,” Obama says. “I think that there are a host of very complicated issues involved there.”

The CIA creates a secure facility where congressional aides will be allowed to view the documents related to the investigation. Feinstein later says the CIA provided a “stand-alone computer system” that was “segregated from CIA networks.”

Aides start sorting through six million pages of documents. The process is initially slow because the CIA hires contractors to read each document before giving it to the committee, to ensure the Senate aides don’t get access to sensitive documents unrelated to the detainee program. “This proved to be a slow and very expensive process,” Feinstein later says.

Around this time, about 870 documents disappear from the computers in the CIA facility where congressional aides are conducting the investigation, Feinstein later alleges.

Another 60 documents allegedly go missing. As Feinstein tells it, CIA personnel first deny that the documents are missing, then blame the IT contractors, then blame the White House. The White House says it did not tell the CIA to remove the documents.

The CIA apologizes for removing the documents, Feinstein later says.

After a preliminary review, the Justice Department’s special prosecutor clears CIA employees of wrongdoing in 99 cases of alleged detainee mistreatment. He recommends that the Justice Department investigate just two cases of detainee deaths.

Reuters reports that the committee has found “no evidence” that CIA torture led to any significant intelligence breakthroughs. At this point, the report is still being finalized.

Feinstein and Sen. Carl Levin, D-Mich., issue a press release saying the CIA’s “enhanced interrogation techniques” did not help the government find Osama bin Laden. They say the committee will complete its review “soon.”

Attorney General Eric Holder announces he is not prosecuting any CIA employees for detainee deaths.