Born into a wealthy Georgia banking family, Mills defied expectations by joining the Marine Corps in 1956. There, he learned the importance of discipline and the finer points of boxing, rising to become a welterweight champion. After his military tenure, Lane attended schools in South Carolina and the University of Nevada-Reno. His distinguished boxing career included the 1960 NCAA Welterweight title and an amateur record of 60 wins and 4 losses. In his last two years at Nevada-Reno, he boxed professionally to help with his tuition costs, going 11-1.
Lane graduated from the University of Utah's College of Law in 1970 and passed the Nevada bar exam before going to work for the Washoe County District Attorney. Mills Lane rose steadily through the legal system, eventually becoming a District Judge in Reno. He stepped down from this position on April 30,1998, and stepped up to a new bench in his own courtroom series. Lane collaborated with J. Edwin Smith on his book, Let's Get It On, which examines his experiences in both the ring and the courtroom.