Rep. Darrell Issa, R-Calif., said Ambassador Thomas Pickering would be deposed on how his Accountability Review Board carried out its probe and whether the Obama administration had any undue influence on the findings.
"We're going to want to go through at length how the ARB reached its conclusions, who it interviewed and why we believe there are shortcomings," Issa said Sunday on NBC's "Meet the Press."
The ARB report released late last year noted system failures and shortcomings that appeared to place the consulate in harm's way. Critics, however, have alleged the report was not thorough and allowed high-ranking Obama administration officials off the hook for both failing to provide adequate security and then downplaying the terrorist role in the attack itself.
Issa said Sunday Pickering and committee member retired Adm. Mike Mullen, former chairman of the Joint Chiefs of Staff, failed to interview key witnesses to the attack, which left Ambassador Christopher Stevens and three other Americans dead.
"One of the problems with this ARB report is, it doesn't seem to find anybody at the high level of State Department or anyone else to have failed," he said.
Pickering responded on the same show that the ARB report was indeed thorough as evidenced by the 29 recommendations it made on improving diplomatic security. He also noted his committee was not tasked to investigate the initial public explanations offered by the administration in the days after the attack.
"With full respect, the Accountability Review Board was there to look at the question of security," said Pickering. "We did not examine talking points after the fact."