Transcript for Trump attorney general nominee grilled on Mueller probe

to build. The high-stakes confirmation hearing for president trump's attorney general nominee, William Barr continuing that confirmation this morning and if confirmed he would oversee special counsel Robert Mueller and he was asked repeatedly Tuesday about how he would handle the ongoing investigation. Our chief justice correspondent Pierre Thomas is in the hearing room there on capitol hill. Good morning, Pierre. Reporter: Robin, good morning. Barr had a goal. He wanted to make clear he is confirmed Bob Mueller will be allowed to finish his investigation and rejected the president's claim that Mueller is on a witch-hunt. First, I believe it is right lil a important the special counsel be allowed to complete his investigation. I have known Bob Mueller for 30 years. On my watch Bob will be allowed to finish his work. Reporter: Barr and Mueller have been friends for three decades. I took it to mean he has respect for Mueller and if Barr disagrees with something Mueller has done he will not be afraid to overrule him if necessary. What did he say about whether or not he would make Mueller's report public? Reporter: Barr said Mueller's final report will be confidential and as attorney general if he's confirmed he will review the report, write his own summary then decide what can be released to the public. If he's confirmed the buck stops with Barr. All right, we'll see what happens. Okay there, Pierre. There was a moment that charmed many yesterday. Barr's 8-year-old grandsonly -- Liam was there. He wrote, I love you so much, you are doing great so far. Isn't that adorable? P.S., I think Russia's people are fine. It is the government is the problem. Out of the mouth of the babes. Senator Dianne Feinstein said the boy deserves a medal for sitting through that. Political analysis. Everything else, insight, support his grandfather.

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