Leigh is a Grapevine, Texas native who never left Texas. A 1987 graduate of Grapevine High School, he moved to the University of North Texas where he took a Bachelor's of Business Administration degree in economics. He then completed a semester of graduate economics courses at Texas A&M University and went to work. First he joined the largest privately held furniture rental chain in the United States. From there, he moved to the southern operating unit of a Fortune 500 less-than-truckload motor freight carrier. After 5 years in industry, he returned to school at Texas Wesleyan University School of Law. There he was a moot court competitor and board member while also serving as Citations Editor of the Law Review.

Leigh is married with two children. He and his family live in Grapevine with an attack chihuahua, a calico cat terrified of children, and a hamster. He is active in civic and church activities. He has served as chief of his daughter's Indian Princess tribe, and as Drumbeater, Assistant Nation Chief, and Nation Chief of the Yo-He-Wah Indian Princess Nation of the Bear Creek Federation of Indian Guides and Princesses. Prior to that he served as a board member and treasurer and chairman of the First Presbyterian Church of Grapevine Preschool Board.