Advocates have called on all Australian states and territories to follow Victoria's lead after it banned gay conversion practices in all settings.
The Change or Suppression (Conversion) Practices Prohibition Bill passed Victoria's upper house 27 votes to nine following a 12-hour sitting on Thursday.
The bill makes it illegal to try to change or suppress a person's sexual orientation or gender identity, with penalties of up to 10 years' jail or $10,000 in fines.
It also empowers the Victorian Equal Opportunity and Human Rights Commission to investigate conversion practices and amends the Family Violence Protection Act to make them a form of domestic violence.
In supporting the bill, Animal Justice Party MP Andy Meddick described himself as the proud father of two "perfect" transgender children.
"They do not need fixing. Nor do any other children or adults who do not fit an often religiously held belief that sexuality and gender are binary only," he said.
Labor's Harriet Shing, the first openly lesbian member of Victorian parliament, called out the "doublespeak" of MPs who were opposing the bill despite saying they supported a ban on conversion practices.
"It is not acceptable that in a debate like this victims and survivors and our communities - my communities - are denied the opportunity to have our equality, our pain and hurt and trauma, on a footing which is of the utmost importance," she said.
The ACT and Queensland passed laws banning gay conversion therapy in 2020, while the Tasmanian Law Reform Institute is conducting an inquiry into the issue.
Victoria's bill, however, goes further than the one passed in Queensland in that it prohibits harmful practices not only in healthcare settings but also in religious settings.
It explicitly bans "carrying out a religious practice, including but not limited to, a prayer-based practice, a deliverance practice or an exorcism" if the person intended to change or suppress an individual's sexual orientation or gender identity.
Just.equal spokesperson Rodney Croome described Victoria's law as "gold-standard".
"We urge other states and territories to follow Victoria's lead," he said.
"That includes Queensland which has a sub-standard law because it fails to address conversion practices in religious settings (in) which most such practices occur."
The coalition did not oppose the bill but moved a number of amendments, including one to pause its progress for further consultation with religious groups. All failed.
Liberal MPs Bev McArthur and Bernie Finn broke party ranks and voted against the legislation, along with crossbench MPs Jeff Bourman, Catherine Cumming, Clifford Hayes, Stuart Grimley, David Limbrick, Tania Maxwell and Tim Quilty.
"This bill is an attack on basic freedoms, it is an attack on freedom of choice, it is an attack on free speech and it is an attack of freedom of association," Mr Finn told parliament.
The coalition leader in the upper house David Davis said while he would "always prefer" the Liberal Party voted as a group, crossing the floor was within party rules.
"The party constitution does allow a conscience vote unlike Labor, which has a situation where an MP who votes against the position of the party is expelled from the party for life," he told reporters on Friday.
Mr Davis said all coalition MPs "strongly opposed" gay conversion therapy.
CEO of Equality Australia Anna Brown said she was "delighted" to see cross-party support of the legislation, which she described as life-saving.
"This vote is a recognition that equality for LGBTIQ+ people can, and should be, supported by conservative and progressive parties alike," she said.
The Australian Federal Islamic Council issued a statement on Friday pledging to work with other faith groups to "mount a legal challenge" against the law.
It will come into effect 12 months after it receives royal assent from Victoria's governor.
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Australian Associated Press