Michael Flynn, former national security adviser to President Donald Trump, pleaded guilty to lying to the FBI about possible collusion between Russia and the Trump campaign. File Photo by Mike Theiler/UPI | License Photo

Dec. 4 (UPI) -- Special counsel Robert Mueller recommended Tuesday that President Donald Trump's former national security adviser, Michael Flynn, not receive any jail time because he has given "substantial assistance" to the Russia investigation.

Flynn, 60, pleaded guilty to lying to FBI investigators on Dec. 1, 2017 -- the first high-ranking Trump adviser to agree to formally cooperate with the special counsel's probe. He is scheduled to be sentenced more than one year later, Dec. 18 by federal Judge Emmet Sullivan in the District of Columbia.


Flynn gave information to the special counsel "shortly after" he was approached, according to a memorandum by Mueller in aid of sentencing.

According to the filing, Flynn has sat for 19 interviews with the special counsel and the Justice Department.

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He has assisted them "on a range of issues, including contact with individuals on the presidential transition team and Russia." A description of how Flynn helped in the Russian interference investigation is redacted.

"His early cooperation was particularly valuable because he was one of the few people with long-term and firsthand insight regarding events and items under investigation by the SCO," special counsel office, according to the memo.

During the campaign, Flynn was a close adviser to Trump. He led a "lock her up" Hillary Clinton chant at the Republican National Convention because of how the Democratic presidential contender dealt with her emails while serving as secretary of state.

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Flynn served in the start of Trump's administration, Jan. 20 to Feb. 13.

Then-acting Attorney General Sally Yates told White House officials on Jan. 26 that Flynn had lied to Vice President Mike Pence about his communications on Russian sanctions with then-Russian ambassador to the U.S. Sergey Kislyak. He was fired two weeks later.

Trump asked then-FBI Director James Comey to let the Flynn investigation go, the fired director has said.

Flynn later filed revised financial disclosure forms revealing payments from three Russian companies with ties to the Kremlin shortly before he joined the Trump campaign. In addition, he retroactively registered with the Justice Department as a "foreign agent" to lobby on behalf of the Turkish government as late as November 2016.

Mueller's memo said the lying offense is "serious," but noted "the defendant's history and characteristics present mitigating and aggravating circumstances." Flynn served in the military for more than 33 years, including five years in combat, and led the Defense Intelligence Agency. He retired as a three-star lieutenant general.

"The defendant's extensive government service should have made him particularly aware of the harm caused by providing false information to the government, as well as the rules governing work performed on behalf of a foreign government," the memo said.

But Flynn "deserves credit for accepting responsibility in a timely fashion and substantially assisting the government," Mueller wrote.