The watchdog wing of Congress has quietly launched an investigation into the “integrity” of the Pentagon’s whistleblower protection program. The previously unreported investigation, started in late October, expands on an ongoing effort by the Department of Justice on this same issue.

The Government Accountability Office, which serves as the investigative arm of Congress, has been looking into the extent to which Department of Defense whistleblower policies “meet executive branch policies and goals,” reassure employees of their rights to raise concerns “without fear of reprisal,” and require officials to report to Congress, among several other areas of concern.

The GAO launched its new investigation on October 27, according to a memo reviewed by The Intercept. A spokesperson for the GAO confirmed the letter, though noted that the investigation was delayed, and there is no estimated release date yet.

The nonprofit Government Accountability Project, which is devoted to protecting whistleblowers, provided The Intercept with documentation on the new investigation. According to the group, the investigation will also likely target senior Pentagon officials accused of destroying evidence that would have exculpated former senior NSA official Thomas Drake, who raised internal complaints about what he believed to be NSA misconduct and waste before ultimately approaching journalists.

Rather than having his concerns acknowledged, Drake spent months fighting charges against him under the Espionage Act, ultimately pleading guilty to just a single misdemeanor. His career in the intelligence community was ended, however.

“Bureaucratic abuses of power are the primary reason otherwise circumspect national security whistleblowers leak to the media. It is too dangerous to work within an untrustworthy system,” Tom Devine, legal director of the Government Accountability Project, wrote in a statement praising the intensified effort to uncover abuses against people, like Drake, who speak out about potential government abuses.

The new effort also follows conclusions made last spring by a separate government watchdog group, the Office of Special Counsel, which is specifically tasked with providing protection to federal whistleblowers. The OSC said there was “substantial likelihood” senior Pentagon officials might have violated “laws, rules or regulations” in Drake’s case by destroying records of his cooperation with Congress and a Pentagon audit concerning his complaints.

The Department of Justice originally said the destruction was “pursuant to a standard document destruction policy,” but that assertion has since been challenged by Drake’s lawyers and the OSC.

“I’m glad to hear that GAO is looking into how a whistleblower’s protected whistleblowing disclosures were destroyed when they were potentially exculpatory evidence in an ongoing criminal case,” Jesselyn Raddack, Drake’s attorney, wrote in an email to The Intercept. “GAO should also investigate how a whistleblower, Drake, ended up being targeted and raided by the FBI in the New York Times leak investigation when he had no involvement in the leak. Hopefully GAO does an aggressive and thorough investigation and recommends meaningful consequences for the officials responsible.”

John Crane, formerly the assistant inspector general in the Pentagon, revealed his role in attempting to protect Drake’s identity and investigate the document destruction involved in his case last May — an effort he claims cost him his job. Crane believes the DOJ and now GAO investigations are vital to repair a broken system of accountability and protection for those willing to identify wrongdoing at personal risk.

“The pattern of events” launched by Drake’s persecution and what followed “are troubling to someone who as assistant inspector general at the DoD helped to craft the Whistleblower Protection Act to protect the disclosure of classified information provided by whistleblowers,” he told The Intercept.

Crane says he became aware of the new GAO investigation recently. The agency does not publicly announce its investigations as a matter of policy.

The implications of the investigation may eventually be important for evaluating the actions of former NSA contractor Edward Snowden, who leaked a massive trove of documents revealing the agency’s worldwide surveillance regime, Crane argues. “The challenge for the incoming Trump administration is that these investigations are in effect examining whether current Pentagon IG leadership has become an existential threat to the national security of the United States by forcing whistleblowers like Snowden to view the media as their court of last resort and the seek safety overseas,” he wrote in a statement.