CIA Chief John Brennan: Effectiveness of Torture 'Unknowable'While CIA director John Brennan acknowledged some of the agency’s tactics were “abhorrent,” he challenged some of the Senate report’s conclusions.CIA Chief John Brennan: Effectiveness of Torture ‘Unknowable’02:57Link copiedDec. 11, 2014, 11:50 PM UTC / Updated Dec. 11, 2014, 9:40 PM UTC