For his investigative work, Mitchell has won more than 20 national awards, including a MacArthur Foundation genius grant and the Sigma Delta Chi Award for Public Service. Mitchell has also received the Heywood Broun Award, the Sidney Hillman Award, the American Legion's Fourth Estate Award, the National Association of Black Journalists' Award for Enterprise Reporting, the Abraham Lincoln Marovitz Award and the Inland Press Association Award. The Southeastern chapter of the American Board of Trial Advocates decided in April 2006 to give Mitchell its first-ever award for Journalist of the Year.