Simpson has spent his career as an advocate for the people of Baldwin and Mobile Counties. Simpson was previously the child victims prosecutor for Baldwin County handling all cases where children are the victims of sexual and/or physical abuse and a career prosecutor, having worked with both the Baldwin County District Attorney's Office and the Mobile County District Attorney's Office for a combined nearly 12 years.

Simpson is a previous chairman of the Baldwin County Republican Party and has also previously served as chairman of the Baldwin County Young Republicans. Simpson has served on the Alabama Republican Party State Executive Committee and is the current ALGOP Vice-Chairman for Congressional District 1.

Simpson has also been very active in the community. He has served on the Board of Directors for Fairhope/Point Clear Rotary Youth Center, The Family Center, and the Baldwin County Department of Human Resources. Simpson is a graduate of the Federal Bureau of Investigations Mobile Division Citizen's Academy (2013) and Leadership Baldwin County (2015).

Simpson's wife, Marina, is the Executive Director of the United Way of Baldwin County. They have two children, John Wallace (11) and Elizabeth (6). Simpson is also an elder at Coastal Church in Daphne.

Representative Simpson's Committee Assignments in the Alabama House of Representatives are- Member - Ethics and Campaign Finance Committee Member - Judiciary Committee Member - Commerce and Small Business Committee Member - Sunset Committee Member - Baldwin County Legislation Member - Mobile County Legislation