A U.S. Army All-American and Rivals250 selection, Mitchel was coached by Chris Melson at Legacy High School where he made 75 tackles in 2010. Considered the No. 24 overall recruit in the state of Texas, the 160th overall recruit in the country and 13th-best cornerback prospect in the nation by Rivals.com, Mitchel snagged a 60-yard touchdown pass on the offensive side of the ball. He was ranked as the 26th-best cornerback prospect in the nation by Scout.com. The Dallas Morning News and Houston Chronicle each ranked Mitchel in its top 100 listing of prospects from the state of Texas. He was voted second-team All-State and was an all-district second-team selection at free safety in Class 5A District Five. Mitchel chose the Razorbacks after also considering Nebraska, among other offers. His father (Eric) played football collegiately for Oklahoma.