Director of the Central Intelligence Agency (CIA) John Brennan pauses before answering a reporter's question during a rare news conference at CIA Headquarters in Virginia December 11, 2014. Brennan said on Thursday that some agency officers used "abhorrent" interrogation techniques and said it was "unknowable" whether so-called enhanced interrogation techniques managed to get useful intelligence out of terrorism suspects. REUTERS/Larry Downing (UNITED STATES - Tags: POLITICS HEADSHOT TPX IMAGES OF THE DAY)