Australian Government

The three branches of the Australian Government

The legislature: Parliament House in Canberra, the seat of the Parliament of Australia

The executive: The Head of State and King of Australia, Charles III, who appoints the governor-general on the advice of the prime minister

The executive: The Governor-General, David Hurley, who by convention follows the Executive Council's advice

The executive: The Prime Minister, Anthony Albanese, representing the Federal Executive Council

The judiciary: the High Court of Australia, the nation's highest court

Section 1 of the Australian Constitution creates a democratic legislature, the bicameral Parliament of Australia which consists of the monarch and two chambers of parliament, the Senate and the House of Representatives. Section 51 of the Constitution provides for the Australian Government's legislative powers and allocates certain powers and responsibilities (known as "heads of power") to the Federal Government. All remaining responsibilities are retained by the six states (previously separate colonies). Further, each state has its own constitution, so that Australia has seven devolved Parliaments, none of which can encroach on the functions of any other. The High Court of Australia arbitrates on any disputes which arise between the Federal Government and the states and territories, or among the states and territories themselves.

The Parliament of Australia can propose changes to the Constitution. To become effective, the proposals must be put to a referendum of all Australians of voting age and must receive a 'double majority': a majority of all votes, and a majority of votes in a majority of States.

The Australian Constitution also provides that the states can agree to refer any of their powers to the Federal Government. This may be achieved by way of an amendment to the Constitution via referendum (a vote on whether the proposed transfer of power from the states to the federation, or vice versa, should be implemented). More commonly powers may be transferred by passing other acts of legislation that authorise the transfer and such acts require the legislative agreement of all the state governments involved. This "transfer" legislation may have a "sunset clause", a legislative provision that nullifies the transfer of power after a specified period, at which point the original division of power is restored.

In addition, Australia has several territories, two of which are self-governing: the Australian Capital Territory and the Northern Territory. While these territories' legislatures exercise powers devolved to them by the Australian Government, the Parliament of Australia has the authority to override their legislation and to alter their powers. Australian citizens in these territories are represented by members of both houses of the Parliament of Australia, albeit with less representation in the Senate. Norfolk Island was self-governing from 1979 until 2015, although it was never represented as such in the Parliament of Australia. The other inhabited territories: Jervis Bay, Christmas Island and the Cocos (Keeling) Islands, have never been self-governing.

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. But the Senate is elected on a basis of equality among the states: all states elect 12 senators, regardless of population. This was intended to allow the senators of the smaller states to form a majority and thus be able to amend or reject bills originating in the House of Representatives. The Australian Capital Territory and the Northern Territory, the only territories represented in Senate, each elect only two.

The third level of governance is local government, in the form of shires, towns or cities. The councils of these areas are composed of elected representatives (known as either councillor or alderman, depending on the state). Their powers are devolved to them by the state or territory in which they are located.

Separation of powers is the principle whereby the three arms of government undertake their activities separately from each other. 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. Only the federal High Court can deem if a law is constitutional or not.

Structure of the Government of Australia

The Australian Senate chamber

The Legislature makes the laws, and supervises the activities of the other two arms with a view to changing the laws when appropriate. The Australian Parliament is bicameral, consisting of the King of Australia, a 76-member Senate and a 151-member House of Representatives.

Twelve Senators from each state are elected for six-year terms, using proportional representation and the single transferable vote (known in Australia as "quota-preferential voting": see Australian electoral system), with half elected every three years. In addition to the state senators, two senators are elected by voters from the Northern Territory (which for this purpose includes the Indian Ocean Territories, Christmas Island and the Cocos (Keeling) Islands), while another two senators are elected by the voters of the Australian Capital Territory (which for this purpose includes the Jervis Bay Territory and Norfolk Island). Senators from the territories are also elected using preferential voting, but their term of office is not fixed; it starts on the day of a general election for the House of Representatives and ends on the day before the next such election.

The members of the House of Representatives are elected by majority-preferential[5] voting using the non-proportional Instant-runoff voting system[6] from single-member constituencies allocated among the states and territories. In ordinary legislation, the two chambers have co-ordinate powers, but all proposals for appropriating revenue or imposing taxes must be introduced in the House of Representatives. Under the prevailing Westminster system, the leader of the political party or coalition of parties that holds the support of a majority of the members in the House of Representatives is invited to form a government and is named Prime Minister.

The Australian House of Representatives chamber

The Prime Minister and the Cabinet are responsible to the Parliament, of which they must, in most circumstances, be members. General elections are held at least once every three years. The Prime Minister has a discretion to advise the Governor-General to call an election for the House of Representatives at any time, but Senate elections can only be held within certain periods prescribed in the Constitution. The most recent general election was on 21 May 2022.

The Commonwealth Parliament and all the state and territory legislatures operate within the conventions of the Westminster system, with a recognised Leader of the Opposition, usually the leader of the largest party outside the government, and a Shadow Cabinet of Opposition members who "shadow" each member of the Ministry, asking questions on matters within the Minister's portfolio. Although the Government, by virtue of commanding a majority of members in the lower house of the legislature, can usually pass its legislation and control the workings of the house, the Opposition can considerably delay the passage of legislation and obstruct government business if it chooses.

The day-to-day business of the House of Representatives is usually negotiated between the Leader of the House, appointed by the Prime Minister, and the Manager of Opposition Business in the House, appointed by the Leader of the Opposition in the Commonwealth parliament.

Courtroom 1 in the High Court in Canberra.

As a federation, in Australia judicial power is exercised by both federal and state courts.

Federal judicial power is vested in the High Court of Australia and such other federal courts created by the Federal Parliament, including the Federal Court of Australia, the Family Court of Australia, and the Federal Circuit Court of Australia. Additionally, the federal legislature has the power to enact laws which vest federal authority in State courts.[13] Since the Australian Constitution requires a separation of powers at the federal level, only courts may exercise federal judicial power; and conversely, non-judicial functions cannot be vested in courts.[14]

State judicial power is exercised by each State's Supreme Court, and such other courts and tribunals created by the State Parliaments of Australia.

The High Court is the final court of appeal in Australia and has the jurisdiction to hear appeals on matters of both federal and state law. It has both original and appellate jurisdiction, the power of judicial review over laws passed by federal and State parliaments, and has jurisdiction to interpret the Constitution of Australia. Unlike in the United States, there is only one common law of Australia, rather than separate common laws for each State.[15]

Until the passage of the Australia Act 1986, and associated legislation in the Parliament of the United Kingdom of Great Britain and Northern Ireland, some Australian cases could be referred to the British Judicial Committee of the Privy Council for final appeal. With this act, Australian law was made unequivocally sovereign, and the High Court of Australia was confirmed as the highest court of appeal. The theoretical possibility of the British Parliament enacting laws to override the Australian Constitution was also removed.[16]

• Prime Minister of Australia
• Australian Public Service
• Referendums in Australia
• States and territories of Australia
• Timeline of the expansion of federal powers in Australia