''My view - a view that I've come to in recent years - is that as a Liberal who believes that commitment and family units are one of the best ways in which society is organised, I support the concept of same-sex marriage,'' Mr O'Farrell said. ''We should, as governments, be encouraging commitment. As societies we should be encouraging commitment. Because, ultimately, people caring for each other works side by side with governments to create better communities.'' "As a Liberal who believes that commitment and family units are one of the best ways in which society is organised, I support the concept of same-sex marriage": NSW Premier Barry O'Farrell. Credit:John Veage At the federal level, Prime Minister Julia Gillard does not favour change but has allowed Labor MPs a conscience vote. But Mr Abbott, who is also opposed, has ruled out a conscience vote for Liberal MPs, a decision viewed as contributing to the failure of same-sex marriage bills last year. Asked about Mr Abbott's position, Mr O'Farrell said Federal Parliament ''ought to reflect the community and allow same-sex marriage. I think in coming to that decision the Federal Parliament should do so by way of a conscience vote across all parties.'' A NSW upper house inquiry is considering whether the state is constitutionally able to legalise same-sex marriage. There has been a hint that the Coalition could change its stance on allowing a conscience vote on gay marriage with Mr Abbott and opposition education spokesman Christopher Pyne indicating that the party room position could change.

Mr Abbott again said on Friday that while the Coalition's policy was that marriage was between a man and a woman, MPs would not be allowed a free vote on the issue of gay marriage. ''It would be up to a party room in a future parliament to decide on [whether to change] this,'' he told ABC radio Melbourne. ''We are not committed for ever and a day to the present position. This will be a matter for a post-election party room. ''Everyone knows where I stand on this and I am happy with the current arrangement [that marriage is between a man and woman]. I accept that not everyone agrees with me on this.'' Asked if New Zealand had proved more progressive than Australia on this issue, Mr Abbott replied that ''in this small respect, New Zealand are different''.

Mr Pyne told Channel 9 that the Coalition's policy could change at the next election, acknowledging that there was support for same-sex marriage. ''I think a lot of people believe recognising same-sex couples - especially for the children of same-sex couples - and supporting commitment is a positive step,'' he said. ''Tony Abbott's made it clear that he hasn't changed his mind on same-sex marriage but the party room could well decide between now and the election or just after the election that we’ll have a conscience vote on it.'' Victorian Premier Denis Napthine, who opposes same-sex marriage, said the issue was one for Federal Parliament. ''The Federal Parliament has debated the issue only recently and it's of note that both Labor Prime Minister Julia Gillard and Tony Abbott both voted against any changes," he told reporters in Canberra on Friday.

Asked if Mr Abbott should allow a free vote of Coalition MPs, he said: ''That's for Tony Abbott and the Coalition at a federal level.'' West Australian Premier Colin Barnett said he did not personally support gay marriage but acknowledged public support for change was growing. ''I think it is a conscience issue,'' he said. ''If it's an issue that comes before parliament in my view it is a free or conscience vote issue.'' In November, a cross-party working group of NSW MPs from the Coalition, Labor and the Greens and an independent gave notice it would introduce the State Marriage Equality Bill in the upper house. Last May the upper house voted 22 to 16 in favour of a motion supporting same-sex equality but many believe legislation to legalise same-sex marriage would be defeated in the lower house.

An upper house Greens MP and member of the cross-party working group, Cate Faehrmann, said Mr O'Farrell's advocacy could change that. ''In relation to the lower house, I don't think you can underestimate what leadership from the Premier means,'' she said. Mr O'Farrell said he was ''not going to campaign on the issue'' but felt the NZ vote presented a ''suitable opportunity'' to express his view. The Premier said he did not believe in using his position in the party room to sway votes on matters of conscience and there was ''sufficient distance'' between his comments and a possible vote in the parliament for that not to happen. Mr O'Farrell said his views were not those he held five or six years ago. ''It's been an evolving thought process with me.'' Hearing the NZ Parliament break into a Maori love song after the vote ''even tweaked at my emotions. You just get a concept of how deeply people feel about this.'' Mr O'Farrell said the argument that same-sex marriage would denigrate the institution of marriage was ''utterly ridiculous''.

Anne Twomey, an associate professor with the law school at the University of Sydney, said NSW had the power to legalise same-sex marriage but raised the possibility that state laws would conflict with the federal Marriage Act. She said a significant potential problem would be how state law connected with Commonwealth laws such as those dealing with de facto relationships, which dictated property rights if a couple broke up. ''It's just very, very difficult. I would be very reluctant to do this.'' Loading Ms Twomey said she could understand why pushing for NSW laws was attractive as ''a political lever'' to spur the Commonwealth to action. ''But given you're mucking around with people's lives, you have to be absolutely confident that you have a system that's going to work and is not going to leave people in complete chaos in their relationships later on,'' she said. Follow the National Times on Twitter