As the House Select Committee on Benghazi prepares for its first hearing this week, a former State Department diplomat is coming forward with a startling allegation: Hillary Clinton confidants were part of an operation to “separate” damaging documents before they were turned over to the Accountability Review Board investigating security lapses surrounding the Sept. 11, 2012, terrorist attacks on the U.S. mission in Benghazi, Libya. According to former Deputy Assistant Secretary Raymond Maxwell, the after-hours session took place over a weekend in a basement operations-type center at State Department headquarters in Washington, D.C. This is the first time Maxwell has...