William DeWitt Mitchell (September 9, 1874 – August 24, 1955) was an American attorney who had served as both Solicitor General of the United States under President Calvin Coolidge and United States Attorney General under President Herbert Hoover.

Though he originally entered Yale with an interest in electrical engineering, after two years his focus shifted to law and he subsequently transferred to the University of Minnesota.

To make up for lost time, Mitchell simultaneously took law courses at night while finishing his undergraduate degree.

This prestige allowed Mitchell access to both the regional council of the U.S. Railroad Administration in 1919, and then he served as chairman of the Citizens Charter Committee of St. Paul in 1922.

He served as a line officer with the 15th Minnesota Volunteer Infantry Regiment and later an acting judge advocate for the United States Second Army Corps during the Spanish–American War.