The House Oversight and Government Reform Committee, led by Chairman Darrell Issa, R-Calif., holds a hearing about last year's deadly assault on the U.S. diplomatic mission in Benghazi, Libya, on Capitol Hill in Washington, Wednesday, May 8, 2013. Left to right are witnesses Mark Thompson, the State Department's acting deputy assistant secretary for counterterrorism, Gregory Hicks, former deputy chief of mission in Libya, and Eric Nordstrom, the State Department's former regional security officer in Libya. House Republicans insist the Obama administration is covering up information about the attack, rejecting administration assurances to the contrary and stoking a controversy with implications for the 2016 presidential race. (AP Photo/J. Scott Applewhite)

Photo by: J. Scott Applewhite

The House Oversight and Government Reform Committee, led by Chairman Darrell Issa, R-Calif., holds a hearing about last year's deadly assault on the U.S. diplomatic mission in Benghazi, Libya, on Capitol Hill in Washington, Wednesday, May 8, 2013. Left to right are witnesses Mark Thompson, the State Department's acting deputy assistant secretary for counterterrorism, Gregory Hicks, former deputy chief of mission in Libya, and Eric Nordstrom, the State Department's former regional security officer in Libya. House Republicans insist the Obama administration is covering up information about the attack, rejecting administration assurances to the contrary and stoking a controversy with implications for the 2016 presidential race. (AP Photo/J. Scott Applewhite)