Lyon received his Bachelor of Arts Degree (Psychology) from the University of Mississippi, attending the Sally McDonnell Barksdale Honors College. He continued his studies in Oxford and later obtained his Doctor of Jurisprudence from the University of Mississippi School of Law while working as part of the Mississippi Innocence Project. Before entering private practice, he gained three years experience in Tennessee state service as an attorney in the Department of Labor. Lyon was admitted to the Tennessee Bar in 2010, and is eligible for admittance to the Mississippi Bar. He is a member of the Tennessee, Nashville and American Bar Associations, and a classically trained violinist.