William Barr, who is facing questions from the Senate, has said he doees not believe Mr Mueller would be involved in a witch hunt and that his predecessor Jeff Sessions “did the right thing” in recusing himself from overseeing the investigation.
Mr Barr will have to navigate his confirmation hearing skillfully, emphasising his support for Mr Trump’s hardline immigration policies while assuring Democrats he will not respect mr Mueller’s independence.
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Hello and welcome to our coverage of the partial government shutdown which has now entered its 25th day.
As well as the shutdown, Will Barr's Senate confirmation begins at 9.30am ET (2.30pm GMT).
Yesterday, Mr Barr sent a letter to head of the Senate Judiciary Committee, Lindsey Graham, saying he believed that as the attorney general nominee he believed that special counsel Robert Mueller's Russia investigation should be allowed to finish its work.
Mr Barr served as attorney general from 1991 to 1993 and has been nominated by President Donald Trump to do the job again. His confirmation hearing Tuesday has multiple story lines worth watching.
Democrats will almost certainly grill Mr Barr on the expansive view of presidential power he has displayed at the Justice Department and in the years since.
That philosophy is freshly relevant now that Mr Barr would be working for a president who appears to relish the power of the office and who has taken unilateral actions, including firing FBI director James Comey last year.
Mr Barr faces a tough task in asserting the Justice Department's independence, and defending the lawyers who work there, while also serving a president who has made demands of loyalty.
Mr Barr insisted on Monday that Mr Trump never sought any promises, commitments or assurances from him before naming him attorney general.
He is set to say the same in his opening remarks.
As for Mr Trump, he is due to have lunch with members of Congress at 12.30pm ET (5.30pm GMT). It is said that a number of moderate Democrats have been invited.
Mr Barr's hearing has started, with the new chair of the Senate Judiciary Committee Lindsey Graham opening proceedings.
He says his "hopes and dreams" for the committee are to achieve as much as possible for the American people.
Mr Graham thanks President Trump for nominating someone in Mr Barr, who is "worthy of the job".
Dianne Feinstein, the top Democrat on the committee, now raises the Mueller investigation. She says “the attorney general must resist political pressure and be committed to defending this investigation.”
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