Hanlon was born in Port Arthur, Texas, and attended Memorial High School. He was a three-year starter at tackle for the football team and also lettered in basketball and track.
After high school, Hanlon accepted a scholarship to LSU, where he played tackle for the Tigers. He was a two-year starter and was named to the All-SEC second team as a senior in 1991.
Hanlon was selected by the Detroit Lions in the fourth round of the 1992 NFL Draft. He played for the Lions for three seasons before being traded to the New York Jets in 1995. He played for the Jets for two seasons before being released in 1997.
After his release from the Jets, Hanlon signed with the Tampa Bay Buccaneers. He played for the Buccaneers for two seasons before retiring in 1999.
Hanlon currently works as a regional sales manager for a medical equipment company.