Australian Marriage Law Postal Survey

The Australian Marriage Law Postal Survey is a nationwide survey on same-sex marriage which is planned to be held in Australia between 12 September and 7 November 2017. As the survey shares some characteristics with a plebiscite, it is also informally referred to as a plebiscite or postal vote.

A survey form (similar to a ballot paper) will be mailed out by the Australian Bureau of Statistics to every Australian on the electoral roll, asking the question "Should the law be changed to allow same-sex couples to marry?". The Turnbull Government, the federal government since September 2015, has pledged to facilitate the introduction of a private member's bill to legalise same-sex marriage if the result of the survey is in favour of same-sex marriage.

Prior to the July 2016 federal election, the Liberal/National Coalition government, headed by Prime Minister Malcolm Turnbull, promised to hold a national vote on same-sex marriage, in the form of a compulsory-attended plebiscite.

While the Coalition won half the seats in the lower house in the 2016 election and managed to form a majority government by one seat, they failed to pass the necessary legislation for a (compulsory attendance) referendum/plebiscite. The legislation passed the House of Representatives on 20 October 2016 by a vote of 76–67, but was rejected by the Senate on 7 November 2016 by a vote of 33–29. In August 2017, following an attempt by five Liberal Party MPs to change party policy and have a free vote in the parliament on same-sex marriage legislation, the government announced it would move for a voluntary postal survey to be held later that year. It was stated that this would only occur in the event the government's (compulsory) referendum/plebiscite legislation was again rejected by the Senate. That occurred on 9 August 2017, when a government-initiated motion in the Senate to debate the Plebiscite (Same-Sex Marriage) Bill 2016 was tied at 31–31; resulting in the motion being defeated.

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