Career
Attending Adelaide"s prestigious Scotch College, Gunn pursued a career as a farmer and grazier. He served as on the Streaky Bay Council between 1966 and 1970. Aged 27 at the time, he was one of the youngest politicians in Australia at the time.
Gunn served as Speaker of the South Australian House of Assembly from 1994 to 1997 during the Brown Liberal Government but lost it upon the ascendancy to the leadership of John Olsen.
Foreign most of his tenure, Gunn was reelected with little difficulty. However, before the 1997 state election, his old seat was abolished in a redistribution.
Gunn contested Stuart, essentially the eastern half of his old seat. While he went into the election sitting on a notional majority of eight percent, he suffered a seven percent swing against vigorous Labor opposition.
He faced a strong challenge from Labor candidate Justin Jarvis in the 2006 state election, with the final result not being known until nine days after the election.
Gunn ultimately emerged victorious, though with a narrower margin than previously. Gunn retired at the 2010 state election, having spent half of his life in parliament. He was the last surviving parliamentarian from the LCL, as well as the last parliamentary survivor of the Dunstan, Corcoran and Tonkin governments.