Each state has a bicameral Parliament except Queensland, which abolished its upper house in 1922. The lower house is called the Legislative Assembly, except in South Australia and Tasmania, where it is called the House of Assembly. Tasmania is the only state to use proportional representation for elections to its lower house; all others elect members from single member constituencies, using the alternative vote.

The upper house is called the Legislative Council, and is generally elected from multi-member constituencies using proportional representation. The three self-governing territories, the ACT, the Northern Territory and Norfolk Island, have unicameral Legislative Assemblies.

The head of government of each state is called the Premier, appointed by the state’s Governor. In normal circumstances the Governor will appoint as Premier whoever leads the party or coalition which exercises control of the lower house (in the case of Queensland, the only house) of the state Parliament.

However, in times of constitutional crisis, the Governor can appoint someone else as Premier. The head of government of a self-governing territory is called the Chief Minister, and likewise they are appointed by the territory’s Administrator, in normal circumstances to whoever controls the territory’s Legislative Assembly.