Transcript for Deputy attorney general to resign from DOJ: Sources

Word that the man overseaing the Robert Mueller investigation, deputy attorney general rod Rosenstein, will soon step down. Our Pierre Thomas asking the new A.G. Pick how he assesses the job Rosenstein has done. That new A.G. Also asked, will he protect the Mueller probe? Reporter: Tonight, word deputy attorney general rod Rosenstein, the man who launched the special counsel Russia probe, is expected to leave the justice department as soon as the new attorney general is confirmed. The president's nominee, William Barr, meeting with senators on capitol hill today. How do you assess the job that Mr. Rosenstein has done? Excellent. Reporter: If he's confirmed, Barr will oversee the Russia investigation. Senators he met with today say Barr expressed deep respect for special counsel Robert Mueller. I asked Mr. Barr directly, do you think Bob, Mr. Mueller is on a witch hunt, he said no. Are you committed to making sure Mr. Muller can finish his job, yes. Reporter: Senator Lindsey graham says Barr told him he is confident Mueller would be quote, "Fair to the president and the country." And Pierre, rod Rosenstein's decision to resign is being seen as a sign that the Mueller investigation may be close to wrapping up? Reporter: That's right, David. Sources are telling me that Mueller is in the final stages of the Russia investigation, and my sources say they do not believe Rosenstein would leave unless he believed Mueller was in good shape. David? Pierre Thomas, thank you. A former commander of the

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