The Western Australian EDO is part of a national network of EDOs servicing each Australian State and Territory. Australia's first EDO was established in New South Wales in 1986. In the early 1990s EDOs were established in Victoria and Queensland.
A group of concerned lawyers joined forces with the Conservation Council of Western Australia Inc to form the Western Australian EDO in late 1995. Funding was obtained from the Commonwealth Attorney-General's Department, and the EDO commenced full time operation in March 1996. The first employees of the EDO were a full-time solicitor (Michael Bennett) and part-time Coordinator (Margaret Robertson). The first Convenor of the EDO was Justice Michael Barker, President of the State Administrative Tribunal of Western Australia.
Like EDOs in other States, the Western Australian EDO operates independently from government.