as he scrambled to obscure the truth about his communications during the presidential transition with Sergey Kislyak, the Russian ambassador to the United States at the time.

Neither his lawyers nor Flynn, the former director of the Defense Intelligence Agency, have explained why he lied to the FBI, a felony that he pleaded guilty to a year ago. But in a memo this week seeking leniency, his lawyers revealed details from the interview that stoked an unfounded theory that Flynn’s relaxed appearance during questioning was potential evidence that he did not actually lie. They also blamed the FBI for not informing Flynn ahead of time that lying to agents is illegal — an argument that prosecutors repudiated.

“A sitting national security adviser, former head of an intelligence agency, retired lieutenant general and 33-year veteran of the armed forces knows he should not lie to federal agents,” prosecutors for special counsel Robert Mueller wrote in court papers. “He does not need to be warned it is a crime to lie to federal agents to know the importance of telling them the truth.”

Leniency for Flynn had all but been assured after Mueller’s prosecutors recommended last week that he receive little or no prison time, crediting his cooperation with their inquiry and other investigations as well as his lengthy military service. His decision to attack the FBI in his own plea for probation appeared to be a gambit for a pardon from Trump, whose former lawyer had broached the prospect last year with a lawyer for Flynn.

The president seized on the case that Flynn made against the FBI in his sentencing memo, defending him on Twitter and on Fox News. “They convinced him he did lie, and he made some kind of a deal,” Trump said of investigators Thursday during the television interview.

That contradicts the narrative that prosecutors have described in court papers. U.S. intelligence had picked up Flynn’s conversations on wiretaps of the ambassador as part of standard surveillance. So the FBI agents had evidence that Flynn was lying when he denied asking Kislyak that Russia refrain from reacting harshly to sanctions imposed by the Obama administration over election interference. He also said he did not remember Kislyak telling him that Moscow had backed off as a result of Flynn’s request.

And prosecutors revealed Friday how far investigators had gone during the interview to give Flynn the chance to tell the truth. At one point, the FBI agents repeated portions of what he had said privately to Kislyak to jog Flynn’s memory. “But the defendant never corrected his false statements,” the prosecutors wrote.

Lawyers for Flynn have tried to minimize his lying to the FBI as an “uncharacteristic error in judgment.” In their sentencing memo, they also seized on the spurious theory that Flynn’s relaxed behavior was exculpatory.

“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,” his lawyers wrote.

The theory about his body language grew out of FBI memos, court papers and revelations about the interview in which the agents have revealed that Flynn appeared “relaxed and jocular” when they arrived at the White House. He offered to give them a tour, and they discussed the hotels where Flynn had stayed during the campaign and the president’s “knack for interior design,” according to court papers.

One agent said Flynn was “unguarded” and “clearly saw the FBI agents as allies,” and he readily answered questions, FBI documents showed. Flynn had a very “sure demeanor” during the interview, according to the senior counterintelligence agent who interviewed him, Peter Strzok, who said he saw no “indicators of deception.”

But prosecutors explained his confidence not as evidence of truth-telling but as a result of the numerous dishonest accounts he had already given about his conversations with Kislyak. “By the time of the FBI interview,” they wrote, “the defendant was committed to his false story.”

James Comey, the former FBI director fired by Trump, testified last week before Congress that the theory being pushed by allies of Flynn about his body language was bogus. “There’s no doubt he was lying,” Comey said.

Indeed, law enforcement officials grew so concerned about Flynn’s contacts with Kislyak and his false explanations for them that they warned the White House that he might be compromised by the Kremlin.

Strzok viewed Flynn as “bright but not profoundly sophisticated,” according to court papers. Strzok, who disparaged Trump in critical text messages and was fired this year for violating bureau policies, has been a frequent target in Trump’s attacks on law enforcement.

Flynn’s disclosures this week about his FBI interview also called into question why he waited until just before his sentencing Tuesday to argue that he was coerced into lying. In pleading guilty last year, he said, “I recognize that the actions I acknowledged in court today were wrong.”

The move also prompted a quick response from the judge presiding over the case, Emmet G. Sullivan of U.S. District Court for the District of Columbia. He ordered that lawyers and prosecutors turn over documents related to Flynn’s Jan. 24, 2017, interview and could question Flynn during his sentencing about why he decided to revisit the circumstances of it nearly a year after pleading guilty.

Sullivan is wary of prosecutorial misconduct. In 2009, he dismissed the ethics conviction of former Sen. Ted Stevens, R-Alaska, and scolded prosecutors, who had withdrawn the charges, for improperly withholding evidence. He took the rare step of appointing a special prosecutor to investigate whether the prosecutors themselves should be charged.

Flynn’s calls to Kislyak, during which he made assurances about the incoming administration, were part of a broader effort by senior Trump officials to create foreign policy before they were in power, and they alarmed FBI investigators who were already scrutinizing Flynn as part of the Russia inquiry.

Prosecutors also reminded the judge that Flynn had made false statements in trying to conceal lobbying work he had done on behalf of Turkey. The Turkish government had paid Flynn more than $500,000 to investigate Fethullah Gulen, a Turkish cleric who lives in Pennsylvania. President Recep Tayyip Erdogan of Turkey believes that Gulen and his supporters were behind a failed coup attempt in 2016 and has repeatedly demanded the United States extradite him.

“The defendant made those false statements while represented by counsel and after receiving an explicit warning that providing false information was a federal offense,” the prosecutors wrote.

This article originally appeared in The New York Times.

Adam Goldman © 2018 The New York Times