After the death of his father from injuries suffered in World War II, Nail and his brother were raised on his grandfather's 70-acre farm in northern Jefferson County. After graduating from Jacksonville State University, he took as job as a high school teacher and assistant football coach, spending two years at Warrior High School and another two at Corner High School. After that he took a higher-paying job with Jim Dandy dog food and was promoted to purchasing manager for the company. He began taking night classes at the Birmingham School of Law. After completing his law degree in 1976 he was hired into Jefferson County District Attorney Earl Morgan's office as a prosecutor in May 1977.
After leaving the District Attorney's office, Nail opened a private practice specializing in criminal defense. He first ran for Judge in 1998, winning the first of three six-year terms on the bench. Due to age limitations, Nail was not eligible to run for re-election in 2016. Michael Streety defeated Gloria Bahakel to take his Place 26 seat in that election.
- Faulk, Kent (January 25, 2017) "From 'outhouse to the courthouse'; Judge Tommy Nail retires." The Birmingham News