After a stint teaching at Murdoch University, Dr. Geoff Gallop was elected Member for Victoria Park in the Western Australian Legislative assembly in 1986 and re-elected in 1989, 1993, 1996, 2001 and 2005.

From 1990 to 1993 he was a Minister in the Lawrence Government (holding a range of portfolios, most notably Education, Fuel and Energy and Minister Assisting the Treasurer). In 1994, he was elected Deputy Leader of the State Parliamentary Labor Party and in 1996 he was elected Leader. At the 2001 general election, Gallop was elected the Premier of Western Australia and was returned to power in 2005. As Premier, he oversaw a range of political and social reforms (electoral reform, gay and lesbian equality and a State Administrative Tribunal), brought a spirit of reconciliation to the resolution of Native Title and developed partnership models for the State’s indigenous communities.

His Government held a Community Drug Summit from 13-17 August 2001. One of the Summit’s 45 recommendations related to a “prohibition with civil penalties scheme” for minor cannabis offences. It was supported by the cabinet and legislation was passed to that end in 2003, making Western Australia the fourth jurisdiction in Australia to adopt that approach. He is a Patron of City Health International, a network of individuals and organizations engaged in the study of and response to structural health issues and health behaviours in the urban environment and an Advocate for Harm Reduction Australia.

He joined the Global Commission on Drug Policy in 2019.