The Commission identified 58 Commonwealth law statutes and provisions that explicitly discriminated against same-sex couples by using the term 'member of the opposite sex'.

[14][15] The previous conservative Howard government banned its departments from making submissions to the HREOC inquiry regarding financial discrimination experienced by same-sex couples.

[16] The report found that 100 statutes and provisions under federal law discriminated against same-sex couples by using the term "member of the opposite sex", from aged care, superannuation, childcare, Medicare (including the Pharmaceutical Benefits Scheme) through to pensions.

A de facto relationship must have ended for the court to make an order for property settlement or spousal maintenance, though this requirement does not exist for married couples.

In his ruling, the judge stated that "de facto relationship(s) may be described as "marriage-like" but it is not a marriage and has significant differences socially, financially and emotionally.

[23] This means partners may have to provide evidence about their living and childcare arrangements, sexual relationship, finances, ownership of property, commitment to a shared life and how they present as a couple in public.

[27] The bill was supported by the opposition Labor Party and came amidst increased public debate on the issue following the judicial legalisation of same-sex marriage in Massachusetts and Canada.

[28] Prime Minister Howard later stated that the amendments were partially motivated by a desire to prevent same-sex couples having their marriages recognised by the courts, as was being litigated at the time.

[37][38] It resolved in August 2015 to hold a national vote on same-sex marriage sometime after the 2016 federal election, in the form of either a plebiscite or constitutional referendum.

[42] Despite initially suggesting the government had "no plans to take any other measures on this issue",[43] Prime Minister Turnbull came under increasing pressure to change policy and allow a conscience vote in the Parliament.

[44] By August 2017, several Liberal Party MPs stated they would consider crossing the floor to suspend standing orders and force debate on same-sex marriage legislation against the government's wishes.

[47] On 9 August 2017, the government directed the Australian Statistician to conduct a survey of all enrolled voters to measure support for same-sex marriage.

[50] The government responded by confirming it would facilitate the passage of a private member's bill legalising same-sex marriage before the end of the year.

[51] The Marriage Amendment (Definition and Religious Freedoms) Act 2017 was introduced by openly gay Liberal Party backbencher, Senator Dean Smith.

[58] Same-sex marriages lawfully entered into overseas automatically became recognised from that date, and the first weddings after the normal one-month waiting period occurred from 9 January 2018.

[65][66] States and territories have long had the ability to create laws with respect to relationships, though Section 51 (xxi) of the Constitution of Australia prescribes that marriage is a legislative power of the Parliament.

[78] Prior to the federal legalisation of same-sex marriage, six Australian jurisdictions (Tasmania, the Australian Capital Territory,[79] New South Wales, Queensland, Victoria and South Australia), comprising 90% of Australia's population, recognised same-sex marriages and civil partnerships performed overseas, providing automatic recognition of such unions in their respective state registers.

[85] As of 2017, only South Australia and the Australian Capital Territory did not require transgender people to divorce before registering an official change of gender on a birth certificate.

[96] Attorney-General Ruddock and other Liberals argued that the bill was necessary to protect the institution of marriage, by ensuring that the common law definition was put beyond legal challenge.

During the bill's second reading, Anthony Albanese, Labor MP for Grayndler said, "what has caused offence is why the Government has rushed in this legislation in what is possibly the last fortnight of parliamentary sittings.

[25] On 13 September 2013, the Australian Capital Territory Government announced that it would introduce a bill to legalise same-sex marriage, following a decade-long attempt to legislate in the area.

[125] Since 2008, the ACT has recognised civil partnerships which provide same-sex couples with increased rights regarding superannuation, taxation and social security.

The Queensland Parliament passed the Discrimination Law Amendment Act 2002 in December of that year, which created non-discriminatory definitions of "de facto partner" with respect to 42 pieces of legislation.

[137][138] The Act provides conclusive proof of the existence of a relationship and ensures participants gain all the rights afforded to de facto couples under state and federal law.

[153][154] In September 2010, the Tasmanian Parliament unanimously passed legislation to recognise same-sex marriages performed in other jurisdictions as registered partnerships under the Relationships Act 2003, making it the first Australian state or territory to do so.

Before the introduction of same-sex marriage nationally, the inability of de facto couples to have conclusive evidence of their relationships in Western Australia and the Northern Territory made it more difficult for them to access rights accorded to them under the law.

The motion was put forward by the Lord Mayor of Darwin, Katrina Fong Lim, and Meghan Hopper, a member of the Council of Moreland.

[235] Indigenous activists also worried that survey forms would not be understood in remote Aboriginal communities as locals are not always fluent in English or "familiar with the process".

[246] In November 2020, the church's Appellate Tribunal approved the right of individual dioceses to formally bless the weddings of same-sex couples married in civil ceremonies.

[286] A Pew Research Center poll conducted between March and May 2023 showed that 75% of Australians supported same-sex marriage, 23% were opposed and 2% did not know or refused to answer.