He is a retired FBI agent and best known for his role in the UNABOM investigation, which resulted in the arrest and conviction of Ted Kaczynski.
In 1987, after eleven years of local police work culminating in his promotion to the rank of sergeant, he was recruited by the Federal Bureau of Investigation.
Upon graduation from the FBI Academy in Quantico, Virginia, Fitzgerald was assigned to the New York Field Division's Joint Bank Robbery Task Force.
[4] Fitzgerald was also responsible for developing training programs and tools to improve the threat assessment capabilities of the FBI.
He continues to work as a private consultant and technical advisor to free media productions, such as Criminal Minds and Sleepy Hollow.