GAY marriage has been legalised in the ACT in an Australian first.

But the new laws, expected to see the first same-sex unions by December, are already headed for a High Court challenge by the Abbott Government.

ABBOTT'S GAY SISTER ENGAGED

The ACT Legislature today passed the Marriage Equality Same Sex Act 2013 by 9 votes to 8 with the support of the Labor Government and its one Greens member.

Congratulations to the ACT! Australia's first jurisdiction to legalise same-sex marriage. — Amnesty Australia (@amnestyOz) October 22, 2013

Opposed by the Liberals, it is the first time such laws have been passed by an Australian Government.

As a large continent of supporters watched from the public gallery, Chief Minister Katy Gallagher said she was sorry a federal threat hung over this bill, but she would not put off the joy of people's weddings.

Result of division, ayes 9 nos 8 therefore Ayes have it. yeah! — Christine Milne (@senatormilne) October 22, 2013

"We are prepared to challenge outdated legal notions," she said, promising to rigorously defend the laws in the High Court.

"It doesn't deter us, it doesn't rattle us and it doesn't change our path.

"We will stand by the view that we are not acting above our station."

It was the responsibility of publicly-elected officials to remove inequality from the community it represented, she said.

Historic step towards equality - same sex marriage bill passed in ACT. Congrats to @KatyGMLA, @ABarrMLA & all who've campaigned for change — Tanya Plibersek (@tanya_plibersek) October 22, 2013

The laws will cover same sex couples only, leaving heterosexual marriages under the Federal Marriage Act.

Late amendments were yesterday made to strengthen the laws against challenge.

Opposition Leader Jeremy Hanson said the last-minute rush gave him no confidence the laws were bulletproof.

The fact was that the issue was a federal one, he said.

It was wrong for the country's smallest government, by just one vote, to change the meaning of marriage for all Australians, he said.

"We do not see the ACT Legislature as a vehicle to drive national and social agendas," Mr Hanson said.

He said those who get married under the new laws should know they would likely be struck down in the High Court.

#Canberra takes a giant step towards being the most LGBTI friendly city in #Australia #MarriageEquality #Canberra 2013 — Andrew Barr (@ABarrMLA) October 22, 2013

Deputy Chief Minister Andrew Barr, who is gay himself, broke down as he spoke of the struggle of gay and lesbian Canberrans and their families.

Mr Barr said he hoped those who married under these laws would live long and happy lives together.

Greens MP Shane Rattenbury called the passing a "landmark moment" and said it should be the start of all governments in Australia striking down inequality.

"This is a reform for ACT citizens and there is no reason ... we should not be addressing this matter," he said.

Calling on Prime Minister Tony Abbott to leave the ACT to make its own laws, he promised the territory would try again if it lost in the High Court.

"Enshrining marriage equality into law is a fight that will go on, no matter the number of hurdles in our way," he said.

The public gallery stood and broke out in rendition of Love is in the Air following the passage of the laws, followed by raucous applause.

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