Responding to a sharply critical Government Accountability Office report on the Defense Contract Audit Agency, Sen. Claire McCaskill (D-Mo.) is demanding the resignations of the DCAA supervisors who pressured employees to soften audit results on federal contractors.

Saying the agency is caught in what could be the “biggest audit scandal in the history of this town,” McCaskill sent letters to DCAA Director April Stephenson and Defense Secretary Robert Gates seeking resignations related to malfeasance in connection with 13 audit reports reviewed by GAO.

The GAO report says DCAA audits were changed to favor government contractors, and auditors were threatened if they refused to change the reports. In several cases, DCAA auditors were harassed and intimidated for cooperating with GAO’s investigation.

DCAA has “gotten caught in what could be the biggest auditing scandal in the history of this town, and I'm not exaggerating here,” McCaskill said on the Senate floor July 24. “I will guarantee you, as auditors around the country learn about this, they're going to have disbelief and raw anger that this agency has impugned the integrity of government auditors everywhere by these kinds of irresponsible actions.”

She said she wants assurance that the supervisors involved have been terminated, as well as further explanations of how the improper actions occurred and how they will be prevented in the future.

Meanwhile, a government watchdog group said the GAO report was not the first time DCAA audits were found not to have complied with generally accepted government auditing standards.

In three separate reports in 2001 and 2002, NASA’s inspector general said DCAA did not follow those standards, according to the Project on Government Oversight.