President Donald Trump’s nominee for attorney general, William Barr, said in written testimony on Monday that he would allow the special counsel investigation against the president to continue.

The president nominated Barr (shown above right) to become the next attorney general on December 7. But critics were concerned Barr’s belief in strong executive powers threatened the ongoing investigation against the president.

Barr addressed those concerns in written testimony a day before he is scheduled to appear before a confirmation hearing starting Tuesday.

“It is in the best interest of everyone — the president, Congress, and, most importantly, the American people — that this matter be resolved by allowing the special counsel to complete his work,” Barr said in written testimony, which was obtained by CNN.

“The country needs a credible resolution of these issues.”

Barr added that he will not permit partisan politics, personal interests or any other improper considerations to interfere with any investigation.

The Senate Judiciary Committee will have the chance to hear his testimony and ask questions during the two-day confirmation hearing. Senate Democrats are planning to ask Barr about the issue when he testifies.

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“I can assure you that, where judgments are to be made by me, I will make those judgments based solely on the law and will let no personal, political, or other improper interests influence my decision,” Barr also wrote. “I will follow the special counsel regulations scrupulously and in good faith, and on my watch, Bob [Mueller] will be allowed to complete his work.”

Senate Democrats and other critics have pointed to past comments Barr made about executive power. He sent a memo last year to the president’s lawyers criticizing the inquiry focusing on allegations that the president obstructed justice.

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Sen. Dianne Feinstein (D-Calif.) called the memo very troubling.

“The memo presents a thoroughly crafted legal argument against investigating the president, with pointed conclusions that the president is above the law,” Feinstein said in a statement on December 20. “We need answers as to why Barr proactively drafted this memo and then shared it with the deputy attorney general and President Trump’s lawyers.”

Barr has been meeting with senators in person over the past few weeks. Senate Judiciary Committee Member Amy Klobuchar (D-Minn.) took the opportunity to ask him whether he would recuse himself from the Department of Justice’s review of the proposed merger of AT&T and Time Warner.

He was a former member of the board of directors at Time Warner. Barr said during the meeting that he would.

“It is critically important that the Justice Department is able to complete an unbiased review of the proposed AT&T-Time Warner merger,” Klobuchar said in a statement Friday. “Given Mr. Barr’s ties to Time Warner, this commitment from Mr. Barr to recuse himself from the Department’s review is necessary.”

Former FBI Director Robert Mueller has been leading the special counsel investigation, which is looking at whether the president or his associates colluded with Russian interests during the campaign. Deputy Attorney General Rod Rosenstein appointed the special counsel and is planning to depart once Barr is confirmed.

Trump has repeatedly accused the special counsel team of being a biased witch hunt against him. Congressional Republicans have also expressed concerns of bias while reviewing the special counsel probe as part of their own investigation.

The president has expressed dissatisfaction with Rosenstein as a result.

The special counsel team has taken down a handful of former associates of the president since launching its investigation back in May 2017. But it has yet to connect the president himself to any collusion allegations; and much of the charges already issued are because of unrelated crime allegations.

Michael Cohen, a former attorney for the president, admitted to lying to lawmakers in federal court about how much he discussed his proposed business project in Moscow with the president as part of his own plea deal.

Trump responded by calling him “weak,” adding that he was only after a lighter sentence for his own crimes.

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Former White House national security adviser Michael Flynn became an early target on of the special counsel team. He resigned a short time into his term when information surfaced that seemingly showed he lied about having a meeting with Russian Ambassador Sergey Kislyak. He formalized a deal with the special counsel to plead guilty in December 2017.

A grand jury indicted former Trump campaign chairman Paul Manafort on multiple charges related to consulting work for the pro-Russian government in Ukraine. The special counsel team had requested the indictment.

Manafort later agreed to cooperate with prosecutors but allegedly violated his plea deal by lying to investigators.

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