The House Select Committee on Benghazi, far from intimidated by its critics, is plowing ahead with a heavy schedule.

Last week, former CIA Director Gen. David Petraeus was deposed by the committee in a closed-door hearing, in which he reportedly offered the committee important clarifications on the CIA’s role in Benghazi—before, during, and after the terrorist attack on Sept. 11, 2012.

Others on the schedule include former Secretary of Defense Leon Panetta, former Deputy Assistant Secretary of State for Diplomatic Security Charlene Lamb, and former Pentagon Chief of Staff Jeremy Bash.

While three of the four have given public testimony before, new information has recently come to light through Freedom of Information Act (FOIA) requests, lawsuits, and the testimony of the 64 witnesses interviewed by the Benghazi committee. Of the 64, 53 told their stories for the first time.

Among the issues the committee will be focused on:

1) The presence of the CIA in Benghazi at the so-called CIA annex about a mile from the U.S. diplomatic compound that came under attack on Sept. 11, 2012.

Its purpose remains shrouded in mystery and has been subject to much speculation. According to Pete Hoekstra, former chairman of the House Select Committee on Intelligence, writing in “Architects of Disaster: The Destruction of Libya,” The diplomatic facility in Benghazi “functioned more as an adjunct of the CIA station, providing cover to many of its operatives than the other way around.”

2) The dispute among the CIA, the State Department, and the White House over the administration’s official talking points on Benghazi.

Petraeus stated publicly, and the CIA wrote in its draft memo, that an orchestrated attack had taken place. The CIA further stated that the security risks in Benghazi were well known. The memo was eviscerated by the National Security Council and State Department staff.

3) The denial of numerous requests for additional security at the diplomatic compound, carrying Charlene Lamb’s signature. It was clear that the local militias on whom State depended for protection of its diplomats were unreliable. In a final journal entry, the day of the attack, Ambassador Chris Stevens bemoaned the lack of security he was dealing with.

4) The revelation in December that military assets in Europe had been identified for a rescue mission. One sent by Jeremy Bash, who has never before testified, to a number of high-ranking Obama administration officials, including at State, asked for the go-ahead to set them in motion. “We have identified the forces that could move to Benghazi. They are spinning up as we speak,” Bash wrote. No reply came.

This email contradicts testimony by then Secretary of Defense Leon Panetta, as well as that of then Chairman of the Joint Chiefs of Staff Martin Dempsey.

If the Benghazi committee sheds light on some of these issues, it will be a major public service.

Its report has the potential to be a textbook in how not to run U.S. foreign policy.