Alderman Barnhill was born and raised in Williamson County. He is a graduate of Franklin High School and the University of Tennessee/Nashville with a B.S. in Business Administration. Alderman Barnhill was first elected to the Board in 1988 and then re-elected in 1989, 1991, 1995, 1999 and 2007.
He currently is serving on the Public Safety and Recreation Committee and the Finance, Administrative, and Community Development Committee.
Alderman Barnhill worked for CPS Corp in Franklin for 39 years and upon retirement became the Executive Director of the J.L. Clay Senior Citizen Center. He has two children: Shannon an attorney with the state of Tenn. and Susan a teacher with the Williamson County School System and two grand children.