Government of South Australia

The form of the Government of South Australia is prescribed in its constitution, which dates from 1856, although it has been amended many times since then. Since 1901 South Australia has been a state of the Commonwealth of Australia, and the Australian Constitution regulates its relationship with the Commonwealth.

Under the Australian Constitution, South Australia ceded certain legislative and judicial powers to the Commonwealth, but retained complete independence in all other areas. In practice, however, the independence of the Australian states has been greatly eroded by the increasing financial domination of the Commonwealth.

South Australia is governed according to the principles of the Westminster system, a form of parliamentary government based on the model of the United Kingdom. Legislative power rests with the Parliament of South Australia, which consists of the Crown, represented by the Governor of South Australia, and the two Houses, the South Australian Legislative Council and the South Australian House of Assembly, with legislative elections held every four years.

Executive power rests formally with the Executive Council, which consists of the Governor and senior ministers. In practice executive power is exercised by the Premier of South Australia and the Cabinet, who are appointed by the Governor, but who hold office by virtue of their ability to command the support of a majority of members of the House of Assembly.

Judicial power is exercised by the Supreme Court of South Australia and a system of subordinate courts, but the High Court of Australia and other federal courts have overriding jurisdiction on matters which fall under the ambit of the Australian Constitution.