Politics of Australia

The politics of Australia operates under the written Australian Constitution, which sets out Australia as a constitutional monarchy, governed via a parliamentary democracy in the Westminster tradition. Australia is also a federation, where power is divided between the federal government and the states. The monarch, currently King Charles III, is the head of state and is represented locally by the governor-general, while the head of government is the prime minister, currently Anthony Albanese.

The country has maintained a stable liberal democratic political system under its Constitution, the world's tenth oldest, since Federation in 1901. Australia largely operates as a two-party system in which voting is compulsory. The Economist Intelligence Unit rated Australia a "full democracy" in 2023.

Like other Westminster-style systems of government, Australia's federal system of government consists of three branches: the legislative (Parliament), the executive (the prime minister, the cabinet, other ministers, and government departments), and the judicature (the High Court of Australia and other federal courts). The Australian government consists of the party or coalition that had majority support in the lower house and exercises both executive (as ministers) and legislative (through control of the House) power.

The federal Parliament (as defined in section 1 of the Constitution) comprises the monarch and is bicameral (has two chambers): the House of Representatives (lower house) and Senate (upper house). The House of Representatives has 150 members, each representing an individual electoral district of about 165,000 people. The Senate has 76 members: twelve from each of the six states and two each from Australia's internal territories, the Australian Capital Territory and Northern Territory.

Separation of powers is the principle the power of state should be shared between multiple bodies, in order to avoid the concentration of power in one entity. The legislature proposes and debates laws that the executive then administers, and the judicial arbitrates cases arising from the administration of laws and common law. However, in accordance with Westminster system, there is no strict separation between the executive and legislative branches, with ministers required to also be members of the legislature. Only the High Court can deem if a law is constitutional or not.

The Australian system of government combines elements derived from the political systems of the United Kingdom (fused executive, constitutional monarchy) and the United States (federalism, written constitution, strong bicameralism), along with distinctive local features, and has therefore been characterised as a "Washminster mutation".

Australia is a federation, with different powers and responsibilities for the three levels of government: the federal government, the states and territories and local government.

The federal nature and the structure of the Parliament of Australia were the subject of protracted negotiations among the colonies during the drafting of the Constitution. The House of Representatives is elected on a basis that reflects the differing populations of the states. Therefore, the most populous state, New South Wales, has 48 members, while the least populated, Tasmania, has only five. This is in contrast to the Senate which is elected on a basis of equality among the states: all states elect 12 senators, regardless of population. This was intended to ensure that smaller states retained influence over legislation and that laws could not be passed with only the support of the more populous states. The Australian Capital Territory and the Northern Territory, the only territories represented in Senate, each elect only two.