US President Donald Trump’s nominee for attorney general, William Barr, on Tuesday appeared before the Senate Judiciary Committee for his confirmation hearing.

Much of the questioning concerned the Robert Mueller investigation and Barr’s ability and willingness to faithfully execute his duties during the investigation. The Committee also probed into his thoughts as to whether Mueller should be permitted to finish the Russia investigation. Barr responded in the affirmative and further stressed his commitment to his duties:

I believe it is in the best interest of everyone, the President, Congress, and the American people, that this matter be resolved by allowing the special counsel to complete his work. The country needs a credible resolution to these issues. And if confirmed, I will not permit partisan politics, personal interests, or any improper consideration to interfere with this or any other investigation. I will follow the special counsel regulations scrupulously and in good faith. And on my watch, Bob will be allowed to finish his work.

Additional, less discussed topics included the False Claims Act, criminal justice reform, civil asset forfeiture and gun control.

Barr was attorney general for former president George HW Bush. Trump announced his renomination in early December, saying: “Bill Barr is one of the most respected jurists in the country—highly respected lawyer … a terrific man, a terrific person, a brilliant man.” The Committee will continue the confirmation hearing on Wednesday.