Referendums in Australia

In Australia, referendums (also spelt referenda) are public votes held on important issues where the electorate may approve or reject a certain proposal. In contemporary usage, polls conducted on non-constitutional issues are known as plebiscites, with the term referendum being reserved solely for votes on constitutional changes, which is legally required to make a change to the Constitution of Australia.

In the past, however the terms were used interchangeably, with the non-constitutional 1916 Australian conscription referendum and the 2009 Western Australian daylight saving referendum being examples.

Voting in a referendum is compulsory for those on the electoral roll, in the same way that it is compulsory to vote in a general election. As of 2023, 45 nationwide referendums have been held, only eight of which have been carried. Of those eight, all but one had bi-partisan support. Since multiple referendum questions are often asked on the same ballot, there have only been 20 separate occasions that the Australian people have gone to the polls to vote on constitutional amendments—of which 8 have been concurrent with a federal election. There have also been three nationwide non-constitutional plebiscites (two on conscription and one on the national song), and one postal survey (on same-sex marriage).

Section 128 of the Constitution specifies that alterations to the Constitution cannot be made without a public vote. A bill containing the amendment must first be passed by both houses of parliament or, in certain limited circumstances, by only one house of parliament. If the bill has only been passed in one house, the governor-general must, under the deadlock provision of section 128, then decide whether or not to submit the referendum to the people. By convention, this is done on the advice of the prime minister. Since the prime minister normally controls the House of Representatives, the effect of this convention is to make it virtually impossible for a referendum to be put to the people if approved by the Senate, but not the House.

If the bill to alter the Constitution is approved by both houses or satisfies the deadlock provision, the bill is submitted to the electors for approval. The referendum is conducted according to the Referendum (Machinery Provisions) Act 1984. If the bill is approved by an absolute majority of both houses, the Constitution provides that it must be submitted to the electors no less than two months but no later than six months after passage. However, this requirement has not always been complied with, with a proposed amendment in 2013 not proceeding to a vote despite the passage of legislation. There is no similar time limitation if the bill is approved by one House of the Commonwealth Parliament only.

To pass a referendum, the bill must ordinarily achieve a double majority: a majority of those voting nationwide, as well as separate majorities in a majority of states (i.e., 4 out of 6 states). This provision, which gives the small Australian states effectively a built-in veto, was one of those constitutional provisions accepted in order for the smaller colonies to agree to Federation. In circumstances where a state is significantly affected by a referendum (such as through an alteration of its borders or through a reduction of its representation), a majority of voters in that state must also agree to the change.

When a referendum question is carried, the amending bill is presented for royal assent by the governor-general.

Prior to the 1977 referendum, only electors in the six states could vote at a referendum. Since the 1977 amendment was carried, voters of the territories have been eligible to vote in referendums. Territory votes are now counted towards the national total but the territories do not count as states for the purpose of the requirement for a majority of states.