(CNN)  Former national security adviser to President Donald Trump Michael Flynn has asked a federal judge to spare him from prison time, according to his defense team’s memo before his sentencing.

He said his cooperation with Robert Mueller’s special counsel investigation “was not grudging or delayed.”

“Rather, it preceded his guilty plea or any threatened indictment and began very shortly after he was first contacted for assistance by the Special Counsel’s Office,” his team wrote.

He is asking for no jail time and has offered to do 200 hours of community service.

Judge Emmet Sullivan of the US District Court for the District of Columbia is scheduled to sentence Flynn next Tuesday. The facts in this case point to a light punishment, and Mueller himself is recommending no prison time, but the decision is up to the judge.

Last week, Mueller told the court that Flynn has provided “substantial assistance” to the investigation and should be spared from going to prison. Court filings revealed that Flynn met 19 times with Mueller’s team and other Justice Department offices, suggesting vast cooperation, though details are still scant as to how he has helped.

Flynn is the highest-ranking Trump official to face charges in the Mueller probe. He pleaded guilty in December 2017 to lying to the FBI about his contacts with the then-Russian ambassador to the US. Flynn initially denied — but eventually said — that they had discussed sanctions and a United Nations resolution during the presidential transition. The saga led to his early exit from the White House.

Meeting with FBI detailed

Tuesday’s filing detailed his account of meeting with FBI investigators near the beginning of the Trump administration and after Flynn had assumed the role of national security adviser.

The FBI chose not to involve the Justice Department when it first approached Flynn at the end of January 2017 to discuss his communications with Russians, Flynn’s defense team said, citing evidence they had reviewed before his sentencing.

Peter Strzok and another FBI agent visited Flynn at his office in the West Wing on January 24, 2017, when he first made the false statements. He did not have an attorney with him at that time, and was not warned he could be prosecuted for making false statements, his memo said.

The FBI “decided the agents would not warn Flynn that it was a crime to lie during an FBI interview because they wanted Flynn to be relaxed, and they were concerned that giving the warnings might adversely affect the rapport,” an FBI agent wrote, according to the evidence cited by the defense team.

Then-FBI Deputy Director Andrew McCabe, who spoke to Flynn before the visit, said that if “Flynn wished to include anyone else in the meeting, like the White House Counsel for instance, that I would need to involve the Department of Justice. [General Flynn] stated that this would not be necessary and agreed to meet with the agents without any additional participants.”

Flynn was in a good mood when he met with the agents that day, the memo said. He “clearly saw the FBI agents as allies,” an FBI agent reported.

Flynn’s defense attorneys said in the memo that even though the FBI agents involved have been hampered by criticism, the former national security adviser continued to own up to lying.

“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 January 24 interview of General Flynn were themselves being investigated for misconduct, General Flynn did not back away from accepting responsibility for his actions,” the defense team wrote.

Different from other Mueller cases

Flynn’s attorneys compared his case with those of defendants in the special counsel’s probe who’ve gone to prison — arguing his situation is much different.

Two other defendants — the Dutch lawyer Alex van der Zwaan and former Trump campaign adviser George Papadopoulos — served 30 days and 14 days, respectively, in jail after pleading to the same crime as Flynn, lying to investigators. But neither of those men helped Mueller with his investigation to the same extent or were as willing to cooperate and accepting of responsibility, write Robert Kelner and Stephen Anthony, Flynn’s attorneys

Among 13 cases where defendants in DC federal court went to sentencing for lying to the federal government, only van der Zwaan and Papadopoulos received prison sentences. The attorneys argued Flynn shouldn’t face the same penalty as those two men, who were warned about the seriousness of the Russia investigation and the consequences they would face for lying when they first spoke to investigators.

Flynn’s likely sentence is between zero and six months in prison.