Gary John Joseph Humphries AO (born 6 July 1958) is a Deputy President of the Administrative Appeals Tribunal. He was a member of the Australian Senate representing the Australian Capital Territory for the Liberal Party of Australia from 2003 to 2013. He was the Chief Minister of the Australian Capital Territory from 2000 to 2001; and was elected to the first parliament of the Australian Capital Territory, in 1989, later representing the Molonglo electorate until 2003.