By agreeing to cooperate with federal prosecutors in a deal announced on Friday, former national security adviser Michael Flynn won for himself protection from further prosecution. That protection could conceivably extend to his son, Michael Flynn Jr, who once worked for his father.

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But what’s in it for the prosecutors?

Court documents made it clear that special counsel Robert Mueller is zeroing in on people very close to Trump, who are identified as a “senior official of the presidential transition team” and a “very senior member of the presidential transition team”.

Those two people – unless they are in fact one person – directed Flynn to hold conversations with the then Russian ambassador Sergey Kislyak about sanctions and about a United Nations resolution on Israel, Flynn admitted to prosecutors after initially lying about the matter.

Those conversations not only give the lie to repeated statements by the president that his team had no contact with the Russians – on Saturday he told reporters there had been “absolutely no collusion” and tweeted that Flynn’s “actions during the transition were lawful” – but they also raise the possibility of serious criminal exposure among members of his inner circle for breaking laws banning communications with foreign entities that undercut US policy.

I think there’s definitely someone even closer to the president in Mueller’s crosshairs Steve Vladeck

Senior members of the transition team included Vice-President Mike Pence; son-in-law Jared Kushner; Reince Priebus, then chairman of the Republican National Committee, later Trump’s chief of staff; Jeff Sessions, then a senator, now the attorney general; and Trump himself.

“I think [Friday’s] news means there’s definitely someone even closer to the president in Mueller’s crosshairs,” Steve Vladeck, co-editor of the Just Security forum and a professor at the University of Texas law school, said in an email. “Regardless of whether that’s Kushner, Sessions, Pence or someone else, it’s not good for the president.”



Three news reports, from Bloomberg, NBC News and BuzzFeed, identified Kushner as the transition team member who directed Flynn to act on the UN resolution, which denounced Israeli settlements.



Flynn was instructed to ask Russia, a member of the UN security council, to block the resolution or vote no, according to court documents. The resolution was exceptional from an American viewpoint owing to the stated intention of the Obama administration to abstain from the vote instead of opposing it. The resolution was passed 14-0.

The sudden spotlight on Kushner was an indication of how fast the Mueller prosecution is moving, and how close it is getting to the top of the food chain.

Facebook Twitter Pinterest Michael Flynn leaves court in Washington. Photograph: Jonathan Ernst/Reuters

Flynn could testify about potentially sensitive interactions involving Kushner, for example a meeting with Kushner and Kislyak during the presidential transition. The Washington Post reported that Kushner proposed a “secret channel” for communications with Russia at the meeting.

Kushner has denied that he proposed such a back channel, and has denied collusion with Russia and other wrongdoing.

But if Trump and his family’s past denials of campaign contacts with Russians fell short of the truth – or if similar denials by Sessions fell short of the truth – Flynn could be in a position to highlight that. He might also be able to describe when the Trump campaign first became aware that Russians had what they called “dirt” on Hillary Clinton – and what the campaign did or did not do with that knowledge.

“Trump has categorically said that he was not aware of any campaign communications with Russia,” said Anne Milgram, who has worked closely in the past with Mueller and his team as a former attorney general for the state of New Jersey and former federal prosecutor.

“That is the kind of question that you would want to ask Michael Flynn. Were there conversations about those communications? Was there an understanding that the Russians had so-called ‘dirt’ on Secretary Clinton? And so all those things are going to be really important for the government to understand.”

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The scope of Mueller’s investigation is unknown, although former prosecutors believe it may go all the way to the top with the special counsel potentially weighing obstruction of justice charges or other charges against the president, who denies all wrongdoing.



The publicly visible legal moves, scant as they are, appear in any case to signify major offstage activity, according to former prosecutors.

“What we see with someone like Michael Flynn that we candidly do not see with the other people who are witnesses, is a very long-term relationship with Trump, a close level of involvement with the campaign,” said Milgram. “We know that he was frequently with Trump, with his family, with other members of the campaign.



“If there is something to be known, it’s likely that Flynn would be someone to have that information. And that’s why he’s so important, because it really does go to the heart of these questions.”

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As a retired three-star general and former head of the Defense Intelligence Agency, Flynn joined the Trump campaign in early 2016 and installed himself as a hub for conversations with foreign operatives and relationships now under the intense scrutiny of prosecutors.

With Flynn’s cooperation, Vladeck said, Mueller could be in position to answer “the million dollar question”: did the Trump campaign collude with Russia during the 2016 election?



“I would imagine that he [Flynn] would have insights into what contacts if any the campaign had with Russian government officials, Russian private citizens, Russian corporations,” Vladeck said. “But I think if there’s dirty laundry, one suspects that Flynn of all people would know what and where it is.”

Milgram counseled against extrapolating too much about what is happening on the inside of the case from what is visible on the outside.



“I would preface what I say by qualifying that we are speculating,” she said. “Because I can tell you by having been involved in countless cases and having read lots of news stories about them – we just don’t know.

“There’s always stuff on the inside that we don’t know. So that’s the caution I would give to you and everybody else.”