Casson graduated from Sandra Day O'Connor College of Law at Arizona State University in 2007. After practicing civil litigation for a few years with a mid-sized firm in downtown Phoenix, he started his own small practice in business law and estate planning. In 2021, Casson and his wife, Lisa, and their two children moved to Maple Grove, Minnesota to be closer to Lisa's family. Casson is licensed in both Minnesota and Arizona. In addition to practicing law, he also teaches law courses in a paralegal program through Phoenix College. He also holds an M.A. in History from Arizona State University.