William J. Walker is a retired United States Army major general and the 38th Sergeant at Arms of the U.S. House of Representatives. He last served as the 23rd Commanding General of the District of Columbia National Guard. This responsibility includes command of the District of Columbia Army and Air National Guard units. Walker previously served in the Drug Enforcement Administration as a Special Agent and was promoted to the Senior Executive Service in January 2003, with his final assignment being Deputy Assistant Administrator in Charge of the Office of Strategic Warning Intelligence. Walker is a member of the Council on Foreign Relations.