Senate confirmation hearings begin today for William Barr, President Trump’s nominee for the attorney general seat left open after Jeff Sessions’s firing in November. Barr, a former attorney general for George H.W. Bush, is known for his expansive view of executive power, but he is reportedly planning on reassuring senators he will protect special counsel Robert Mueller’s Russia probe, according to prepared testimony. Barr’s opening statement says that it is “vitally important” Mueller be allowed to complete his investigation. Democratic senators are expected to press Barr over an “unsolicited memo” he sent to Deputy Attorney General Rod Rosenstein in June in which he criticized Mueller’s investigation. In addition to sending the memo to Rosenstein, Barr acknowledged he also shared it with most of Trump’s lawyers and discussed it with several of them. We’ll have more on this story later in the program with Vince Warren of the Center for Constitutional Rights.