Barber spent 35 years in the district attorney's office, joining in 1972 and working there until 1983. After spending a year in private practice, he ran successfully for district attorney in 1984. As chief prosecutor in the 10th Judicial Circuit, Barber established a special unit in 1991 to focus on bad-check cases, and set up a restitution recovery program in 2002 to assist crime victims.
Barber was elected to the position 5 times. His term was to expire in 2010. Barber announced his resignation on July 25, 2008, effective September 1. Governor Bob Riley appointed his successor, deputy district attorney Brandon Falls, in August.