Transcript for Michael Flynn a key cooperating witness: Special counsel

There is news from the Russia investigation this evening. Robert Mueller is recommending former trump national security adviser Michael Flynn be given no prison time. But the documents filed by Mueller now reveal new clues tonight, including the 19 meetings Flynn had with Mueller's team, and with other investigators. Here's ABC's chief justice correspondent Pierre Thomas now. Reporter: The only white house official to cut a deal with Robert Mueller, Michael Flynn, is now billed as a key cooperating witness. Newly-released court documents reveal he sat down with investigators 19 times, providing, quote, "Substantial assistance" after pleading guilty to lying about his contacts with Russia during the transition. A dramatic turnaround for one of president trump's earliest and most vocal advisers. The man who repeatedly called for Hillary Clinton to be jailed. Yeah, that's right. Lock her up. Reporter: Mueller is recommending Flynn face no prison time himself, after providing "First-hand information about the content and context of interactions between the transition team and Russian government officials." The special counsel says Flynn is helping with as many as two other investigations. No details, though. Much of last night's court filing is redacted -- blacked out. And David, more expected this week from Mueller. He is expected to give details on the lies and crimes he's accusing Paul manafort committing, while agreeing to cooperate. And we'll hear who he -- how confident Michael Cohen has been. David? Pierre Thomas, following it all. Pierre, thank you.

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