WASHINGTON – Attorneys for former national security adviser Michael Flynn requested late Tuesday that the retired Army lieutenant general spend no time in prison and be sentenced to one year of probation based on his cooperation with Russia special counsel Robert Mueller.

Flynn's attorneys made their case in court documents filed in advance of his Dec. 18 sentencing date.

"General Flynn’s respect for the law is demonstrated by his decision to accept responsibility for his actions soon after the Special Counsel’s Office reached out to him and sought his cooperation," Flynn's lawyers said.

The attorneys, however, did offer a new account of Flynn's interactions with FBI agents during a Jan. 24, 2017 interview in which the newly installed national security adviser, without a lawyer present, lied about his contacts with Russia ambassador Sergey Kisylak.

Prior to the interview, the attorneys said, FBI officials had decided that they would not warn Flynn about the criminal consequences for lying to federal agents.

"One of the agents reported that General Flynn was 'unguarded' during the interview and 'clearly saw the FBI agents as allies,' " the Flynn document stated.

The attorneys noted that the interview had been arranged by then-Deputy FBI Director Andrew McCabe, who was subsequently fired for unauthorized disclosures to reporters. One of the interviewing agents was Peter Strzok, a senior counter-intelligence agent who was ultimately dismissed for making disparaging comments about candidate Donald Trump in text messages exchanged with an FBI lawyer, who was Strzok's girlfriend.

"Even when circumstances later came to light that prompted extensive public debate about the investigation of General Flynn, including revelations that certain FBI officials involved in the Jan. 24 interview of General Flynn were themselves being investigated for misconduct, General Flynn did not back away from accepting responsibility for his actions," Flynn's attorneys said.

Last week, Mueller's prosecutors provided an account of Flynn's extensive cooperation, citing the former general's "substantial" assistance to the Russia inquiry and at least two other undisclosed investigations in recommending that he serve no prison time.

Flynn, according to prosecutors, has met with investigators 19 times since he pleaded guilty last year to lying to the FBI about his contacts with Kislyak during the run-up to President Donald Trump's inauguration.

Flynn's expansive discussions with Mueller's team stand in stark contrast to the interactions involving former Trump campaign chairman Paul Manafort, whose lawyers were due in court Tuesday to respond to prosecutors' assertions that Manafort had repeatedly lied to them, in violation of a cooperation agreement brokered in September.

Manafort pleaded guilty to financial fraud to avoid a second trial in the District of Columbia following his August conviction on related financial fraud charges in a Virginia federal court. The collapse of the plea agreement exposes the 68-year-old Manafort to a possible decade-long prison sentence in the D.C. case alone.

Prosecutors, meanwhile, lauded Flynn's assistance, claiming that his early guilty plea and decision to cooperate "likely affected the decisions of related firsthand witnesses to be forthcoming with the (special counsel’s office) and cooperate.”

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"The defendant’s record of military and public service distinguish him from every other person who has been charged as part the (special counsel's) investigation," prosecutors said. "However, senior government leaders should be held to the highest standards. 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."

Flynn, who memorably called for the jailing of Democrat Hillary Clinton during the 2016 Republican convention, admitted to lying during an FBI interview about his conversations with Kislyak, Russia’s former ambassador to the United States. Flynn discussed U.S. sanctions with Kislyak on Trump’s behalf during the presidential transition and said members of the president’s inner circle were aware of, and in some cases directing, his efforts, according to the plea.

Flynn had urged Kislyak not to respond to sanctions imposed by the Obama administration in response to Russian election interference.

Flynn’s FBI interview came just weeks before he was forced to resign in February 2017. The White House said he was fired for misleading Vice President Mike Pence and other senior officials about the content of his conversations with Kislyak.

As part of his plea, Flynn also admitted to lying about Turkish lobbying and research work. He belatedly registered with the Justice Department as a foreign agent for the work weeks after he left the White House.

In court documents Tuesday, Flynn's lawyers also cited the Army general's extensive public service record of more than three decades, including testimonials from a long list of former military colleagues, friends and family.