For more than three years, beginning in 2009, staff members of the US Senate intelligence committee spent their days combing through millions of Central Intelligence Agency documents about its interrogations of suspected terrorists.
Several years later, documents they uncovered have become the focus of a ferocious political battle pitting the CIA against Senator Dianne Feinstein, the senior legislator overseeing the agency as chair of the intelligence committee.
In a 40-minute Senate speech this week, Ms Feinstein accused the agency of trying to “intimidate” the committee to prevent it from reporting the truth about the interrogations.