A Cocke County native, Dunn was one of eleven children of James J. and Marian Hall Dunn, growing up in Newport, where he graduated from Cocke County High School in 1965.

Dunn graduated from Walters State Community College and East Tennessee State University, where he studied English with an interest in teaching and majored in criminal justice. He graduated from the Federal Bureau of Investigation National Academy in Quantico, Virginia. Later, while working with the Tennessee Department of Safety, he attended the Nashville School of Law from 1983-1986.  He was admitted to the Tennessee Bar in October 1986 and the Federal Bar of the Middle District of Tennessee in 1986.

He and his wife, Karene, have a daughter, Lauren, and a son, Bruce.

Before he became an attorney, Dunn served his nation by joining the Army and serving as a military police officer in Germany from 1966-1968.  He was a member of the 30th Military Police Battalion.

Currently, Dunn serves on the Tennessee Public Safety Coalition, comprised of the Tennessee Police Chiefs’ Association, the Tennessee Sheriffs’ Association, and the Tennessee District Attorney Generals’ Association. Dunn is the voting member for the District Attorneys. The Public Safety Coalition works together to improve legislation for the safety of all Tennesseans.

District Attorney General Dunn has been elected to serve as a member of the Executive Committee of the Tennessee District Attorneys General Conference. As a member of the executive committee, He participates in oversights of the Conference administration, including budgeting, accounting, payroll, personnel, and property management for all district attorney offices throughout the state.