On 7 September 1966, Kevin Lyons (the son of former Premier and Prime Minister Joseph Lyons) resigned from the state Liberal Party after a dispute over preselection, and on 15 October formed the Centre Party. In 1969, Lyons held the balance of power, and offered his support to Bethune to form government with himself as Deputy Premier. Bethune accepted. This forced Labor Premier Eric Reece to resign on 26 May, making Bethune the first non-Labor Premier of Tasmania in 35 years, and the first to hold the post since the main non-Labor party in Tasmania adopted the Liberal banner in 1946. He also served as his own Treasurer.