WASHINGTON — Federal prosecutors rebuffed a judge’s order to release by Friday highly classified transcripts of discussions that Michael T. Flynn, the president’s former national security adviser, had with the Russian ambassador during the presidential transition.
The transcripts between Mr. Flynn and Sergey I. Kislyak, formerly Russia’s top diplomat in the United States, were expected to show that they talked in December 2016 about sanctions that the Obama administration had just imposed on Russia. Mr. Flynn initially denied those exchanges about sanctions both to Trump administration officials and the F.B.I. in the weeks after the discussions.
The conversations prompted concerns among senior Obama administration officials about whether the Trump transition team was flouting norms about holding off on making policy until after taking office. The phone calls were also at the center of the scandal that eventually prompted Mr. Flynn’s ouster just weeks into President Trump’s term.
The order this month from the judge, Emmet G. Sullivan of the Federal District Court in the District of Columbia, was unusual. The transcripts came from a secret F.B.I. wiretap of Mr. Kislyak, and their release would have provided an extraordinarily rare look at the fruits of the government’s eavesdropping. Agents routinely listen to wiretaps of foreign officials, but they remain among the government’s most closely held secrets.
The calls between Mr. Flynn and Mr. Kislyak were referenced repeatedly in court documents and the special counsel’s report on Russian election interference but never released, and prosecutors have not acknowledged the existence of the wiretap. Judge Sullivan, who is overseeing Mr. Flynn’s case, ordered that audio recordings of his conversations with Mr. Kislyak be made public along with a voice mail message made by the president’s lawyer.
The Justice Department’s refusal to comply with the judge’s order made clear that prosecutors had no interest in confirming the wiretap, which was approved by the secretive Foreign Intelligence Surveillance Court.
“This would be a rare step to make public” such intelligence collection, said Joshua Geltzer, a former Justice Department official. “What you see in today’s filing is the government trying to avoid disclosing that material.”
Instead, prosecutors asserted that they did not need to provide the transcripts because they were, in the end, not vital to the prosecution of Mr. Flynn. He pleaded guilty in December 2017 to lying to the F.B.I. after agents interviewed him about what was said on those calls.
“The government further represents that it is not relying on any other recordings, of any person, for purposes of establishing the defendant’s guilt or determining his sentence, nor are there any other recordings that are part of the sentencing record,” prosecutors wrote in a court filing responding to Judge Sullivan’s order.
In another filing on Friday, prosecutors did comply with Judge Sullivan’s order to make public the message that Mr. Trump’s former personal lawyer John Dowd left for Mr. Flynn’s lawyer, Robert K. Kelner. Mr. Dowd left the message after learning on Nov. 22, 2017, that Mr. Flynn had withdrawn from a joint defense agreement with the president. The contents of that voice mail were first disclosed last month in Mr. Mueller’s report.
In a statement, Mr. Dowd called the special counsel’s reporter “a baseless, political document designed to smear and damage the reputation of counsel and innocent people.” He also said that Mr. Mueller never asked him about the voice mail “despite numerous opportunities to do so.”
Mr. Flynn’s calls with Mr. Kislyak took place after the Obama administration had imposed sanctions on Moscow for interfering in the 2016 presidential election. The sanctions alarmed Trump transition officials, who were hoping to improve relations with the Russian government.
Mr. Flynn had asked Mr. Kislyak that Russia refrain from escalating tensions in response to the Obama administration’s sanctions on Moscow for interfering in the 2016 election.
When questioned by the F.B.I. on Jan. 24, 2017, Mr. Flynn told agents that he had not made that request. He also lied about discussing Russia’s vote on an impending United Nations resolution to condemn Israeli settlements in the West Bank. He has since admitted that he asked that Russia either delay or oppose the resolution.
“F.B.I. agents gave the defendant multiple opportunities to correct his false statements by revisiting key questions,” prosecutors wrote in a sentencing memo in December. “When the defendant said he did not remember something they knew he said, they used the exact words the defendant had used in order to prompt a truthful response.”
In early February 2017, White House officials reviewed for about an hour the transcripts of calls between Mr. Flynn and Mr. Kislyak, according to a confidential memo by White House lawyers that detailed how some of Mr. Trump’s confronted the situation surrounding Mr. Flynn. Vice President Mike Pence reviewed at least some portions of the transcripts, according to the memo.
Mr. Trump fired Mr. Flynn that month after administration officials concluded based on their review of the transcripts that he had been untruthful to Mr. Pence and other officials about the substance of his talks with Mr. Kislyak.
Mr. Flynn’s supporters and the White House have tried to play down his actions, suggesting that investigators entrapped him or that his body language during the interview with agents showed he was not lying.
Judge Sullivan rebuked Mr. Flynn for his conduct and raised concerns that Mr. Flynn’s lawyers were suggesting in presentencing memos that the F.B.I. agents who question him may have tricked him by failing to warn that lying to investigators was a crime.
“This sounds like a backpedaling on the acceptance of responsibility,” Judge Sullivan said during Mr. Flynn’s sentencing hearing in December. The judge delayed the proceeding to give Mr. Flynn time to complete his cooperation with investigators in other federal cases.
The judge said during that hearing that he found no fault with the conduct of the F.B.I. or prosecutors, and Mr. Flynn admitted that he knew at the time that agents questioned him that lying to the F.B.I. is a crime, and he once again acknowledged his guilt. Mr. Flynn also declined to challenge the circumstances surrounding the F.B.I. interview.