Trump's defence secretary presided over investigation into his national security adviser for disclosing classified secrets

President-elect Donald Trump’s pick for secretary of defence once presided over an investigation into the unauthorised disclosure of classified information to foreign allies that was carried out by Trump’s pick for national security advisor, according to a new report from The Washington Post.

According to the Post, a 2010 investigation of Lt. Gen. Michael Flynn found that he shared “classified information with various foreign military officers and/or officials in Afghanistan without proper authorization.” Post sources said the secrets were about CIA operations in Afghanistan.

Flynn was never disciplined, documents released to the Post under the Freedom of Information Act showed, since it was not “done knowingly,” and the investigation found the disclosures were not damaging to national security.

The investigation was ordered by the commander of US Central Command, which was led by Marine Gen. James Mattis from August 2010 to March 2013. The released documents do not name Mattis, so it is possible it was initiated by his predecessor, acting-commander Lt. Gen. John Allen, or Gen. David Petraeus, who served in the post until June 2010.

Mattis, Trump’s nominee to lead the Department of Defence, did not respond to a request for comment.

The investigation by Central Command held the then-Maj. Gen. Flynn back from promotion for an entire year until it was concluded. He was then promoted to lieutenant general and assigned to the Office of the Director of National Intelligence in September 2011.

“That was substantiated because I actually did it,” Flynn told the Post of his disclosures in August. “But I did it with the right permissions when you dig into that investigation. I’m proud of that one. Accuse me of sharing intelligence in combat with our closest allies, please.”

The documents from the investigation however, which stemmed from the complaint of an anonymous Navy intelligence specialist, showed Flynn shared intelligence “without proper authorization.”

Flynn went on to serve as the commander of the Defence Intelligence Agency, until he was forced out due to reported mismanagement.

In November, NBC News reported that Flynn personally crossed out Mattis’ name from a list of Trump’s candidates for national-security positions. Transition sources who spoke with The Washington Post that month also said Flynn, a retired three-star general, did not want any military officer who outranked him to be part of the Trump Cabinet.

Flynn’s early lobbying efforts were apparently unsuccessful. So far, Trump has nominated two four-star generals to his Cabinet: Mattis to lead the Defence Department and Marine Gen. John Kelly to head the Department of Homeland Security.

Flynn’s sharing of classified information was not his first foray into rule-bending. While at DIA, Flynn had installed a secret internet connection in his Pentagon office, despite his office likely already having connections to the Internet that were monitored and secured by military standards.

The general has been under increased scrutiny since being named Trump’s national security adviser, especially considering his repeated criticised Hillary Clinton on the campaign trail for using a private email server while she was secretary of state.

“So there seems to be a standard for the Clintons that’s not the same standard for the rest of America,” Flynn told The Heritage Foundation.

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