Transcript for New questions about scope of Kavanaugh FBI investigation

All eyes are on Washington and the FBI investigation into sexual misconduct allegations against judge Brett Kavanaugh. Overnight Jeff flake and Chris coons revealed how they came together to call for the investigation. Backed by the white house, but under intense scrutiny. Our senior congressional correspondent, Mary Bruce, is tracking it all. She is there on capitol hill. Good morning, Mary. Reporter: Good morning, robin. The clock the ticking on this one-week FBI investigation, but this morning, there are new questions about the scope of this review and what it could all mean for Kavanaugh's nomination and we're learning new details about how this all came about. The rare bipartisan deal that sparked this investigation. This confrontation between a protester and Republican senator Jeff flake set the wheels in motion for that surprise deal. The protester begging him to hold out for an FBI investigation into judge Kavanaugh. What are you doing, sir? Clearly passionate and determined that I hear them. Reporter: His close friend, democratic senator Chris coons offered a potential solution. I wish we would take a one-week pause. One week only. Reporter: Flake listened intently, and when the Democrat finished speaking, flake stood up motioning for coons to follow him out of the room. We squeezed into a phone booth, and we barely fit in talking to another senator and there is a committee outside. Reporter: Almost two hours later, flake announced the dramatic move demanding a delay so the FBI can investigate, suggesting he wouldn't support Kavanaugh unless they did. This morning, that investigation is now under way, but weighing heavily on the outcome, whether Kavanaugh misled the committee and if that would kill his nomination. After resisting it for weeks, president trump is now embracing the investigation. They have free rein. They'll be doing things we never even thought of, and hopefully at the conclusion, everything will be fine. Reporter: But Democrats worry the white house is limiting the scope of the investigation. We are hearing reporting that they are somehow trying to limit this. I'm very concerned about this because the white house should not be allowed to micromanage an FBI investigation. Reporter: The white house is pushing back. The white house isn't intervening. We're not micromanaging this process. This has become a national disgrace dollars and his fingerpointing. Fear has been unfairly stoked about my judicial record. Nge on behalf of the Clintons and millions of dollars in money from outside left wing opposition groups. That he would accuse Democrats of sol kind of a vast conspiracy to do him in and even dragged in Hillary Clinton, I found that bizarre, but we hardly need somebody on the supreme court who has these conspiracy theory notions. Reporter: Amid the fallout "Saturday night live" offering their spin on Kavanaugh's intense testimony. I'm going to start at an 11. I'm going to take it to about a 15 real quick. Reporter: And poking fun at his repeated references to beer. Now I'm usually an optimist. I'm a keg is half full kind of guy. Reporter: They did not hold back. Now this morning, Rachel Mitchell, the Republican prosecutor hired to lead the Republican questioning during this hearing, she has reportedly written a memo outlining why Kavanaugh couldn't have charges against him. A he said/she said case is hard to prove, and she is arguing this is a job interview and not a trial. Absolutely. Thank you.

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