In ordinary circumstances, the leader of the party or coalition that has the confidence of the House of Representatives is entitled to become prime minister and form a government. Generally, a party or coalition will have a majority in the lower house in order to provide confidence, however in periods of minority government, the larger party will rely on confidence and supply from minor parties or independents. By convention, the prime minister must be a member of the lower house. The only case where a member of the
Senate was appointed prime minister was
John Gorton, who subsequently resigned his Senate position and was
elected as the
member for Higgins in the House of Representatives. The prime minister is formally appointed to the role by the governor-general under section 64 of the Australian Constitution, however their choice is limited in normal circumstances to the individual with the confidence of the lower house. However, the prime minister (and all other ministers) must be a parliamentarians or become one within three months to be a minister. There are no term limits for the prime minister, and they are generally entitled to continue in their role whilst they retain the confidence of the lower house. Individuals most commonly cease to become prime minister after losing an election by not obtaining a majority in the lower house (at which point they generally become leader of the opposition or resign) or through replacement by their parliamentary party colleagues. This later method has become increasingly common, with the office changing hands four times due to parliamentary spill and only twice due to an election in the period following the election defeat of John Howard in 2007 to the election of Anthony Albanese in 2022. A prime minister may also lose their position following a vote of no confidence in the government or due to a failure to pass supply through the lower house. In either event, the prime minister is required by convention to either resign or call an election. Whether a prime minister is required to resign or call an election following an inability to pass supply through the Senate was the animating issue of the
1975 constitutional crisis. In that event, governor-general Sir John Kerr dismissed the Whitlam government following the Senate's deferral of the government's budget and demand that they would not pass supply until the government called an election. The constitutional propriety of the governor-general's action during that period remains subject to vigorous debate. being sworn in as the 19th Prime Minister on 10 January 1968. To date, Gorton is the only Senator to have served as Prime Minister, though he would swiftly move to the House of Representatives as the member for
Higgins. Despite the importance of the office of prime minister, the Constitution does not mention the office by name. The conventions of the
Westminster system were thought to be sufficiently entrenched in Australia by the authors of the Constitution that it was deemed unnecessary to detail these. Indeed, prior to Federation in 1901 the terms "premier" and "prime minister" were used interchangeably for the head of government in a colony. Following a resignation in other circumstances or the death of a prime minister, the governor-general generally appoints the
deputy prime minister as the new prime minister, until or if such time as the governing party or senior coalition party elects an alternative party leader. This has resulted in the party leaders from the Country Party (now named
National Party) being appointed as prime minister, despite being the smaller party of their coalition. This occurred when
Earle Page became caretaker prime minister following the death of
Joseph Lyons in 1939, and when
John McEwen became caretaker prime minister following the
disappearance of Harold Holt in 1967. However, in 1941,
Arthur Fadden became the leader of the Coalition and subsequently prime minister by the agreement of both coalition parties, despite being the leader of the smaller party in coalition, following the resignation of
United Australia Party leader Robert Menzies. Excluding the brief transition periods during changes of government or leadership elections, there have only been a handful of cases where someone other than the leader of the majority party or coalition in the House of Representatives was prime minister: • , at the central table in the
House of Representatives in 1901.
Federation occurred on 1 January 1901, but
elections for the first parliament were not scheduled until late March. In the interim, an unelected
caretaker government was necessary. In what is now known as the
Hopetoun Blunder, the governor-general,
Lord Hopetoun, invited Sir
William Lyne, the
premier of the most populous state,
New South Wales, to form a government. However, no politician would agree to be a member of his Cabinet and Lyne returned his commission before Federation actually took place. The governor-general instead then commissioned the much more popular
Edmund Barton, who became the first prime minister on Federation and led the inaugural government into and beyond the election. • During the second parliament, three parties (Free Trade, Protectionist and Labor) had roughly equal representation in the House of Representatives. The leaders of the three parties,
Alfred Deakin,
George Reid and
Chris Watson each served as prime minister before losing a vote of confidence. • As a result of the
Labor Party's split over conscription,
Billy Hughes and his supporters were expelled from the Labor Party in November 1916. He subsequently continued on as prime minister at the head of the new
National Labor Party, which had only 14 members out of a total of 75 in the House of Representatives. The
Commonwealth Liberal Party – despite still forming the official Opposition – provided confidence and supply until February 1917, when the two parties agreed to merge and formed the
Nationalist Party. • During the
1975 constitutional crisis, on 11 November 1975, the governor-general, Sir
John Kerr, dismissed the Labor Party's
Gough Whitlam as prime minister. Despite Labor holding a majority in the House of Representatives, Kerr appointed the Leader of the Opposition,
Liberal leader
Malcolm Fraser as caretaker prime minister, conditional on the passage of the Whitlam government's
Supply bills through the
Senate and the calling of an election for both houses of parliament. Fraser accepted these terms and immediately advised a
double dissolution. An election was called for
13 December, which the Liberal Party won in its own right (although the Liberals governed in a coalition with the Country Party). Compared to other
Westminster systems such as those of
Canada's federal and provincial governments, the transition from an outgoing prime minister to an incoming prime minister has been brief in Australia since the 1970s. Prior to that, in accordance with longstanding Australian constitutional practice, convention held that an outgoing prime minister would stay on as a caretaker until the full election results were tallied. Starting with the
1972 Australian federal election on 2 December 1972, Gough Whitlam and his deputy were sworn in on 5 December 1972 to form an interim government for two weeks, as the vote was being finalised and the full ministry makeup was being determined. On 23 May 2022
Anthony Albanese became prime minister with an interim four person ministry, two days after his victory in
the election. This rapid shift was done in order for the new PM to attend a
Quad meeting scheduled shortly after the election. When the results of the election were more clearly known the entire ministry was sworn in on 1 June 2022. ==Amenities of office==