Gay rights advocates are supporting a bill in the Queensland Parliament that seeks to recognise same-sex unions. The bill was introduced by Deputy Premier Andrew Fraser.

Alex Greenwich of the advocacy group Australian Marriage Equality told a parliamentary committee Friday that recognising gay marriages would provide same-sex couples with evidence of their relationship, which could be useful for next-of-kin situations and medical emergencies.

Greenwich said the bill should not be controversial because it would just keep Queensland up to date with other Australian states and territories.

"Queenslanders are already accepting of same-sex couples. The state should be following public attitudes," he told News.com.au.

Narelle Oliver of the Independent Catholic Church of Australia, who wants her union with her female partner of five years to be recognised by the state, said having the state legally acknowledge their marriage is a powerful statement.

"My sexuality has been described as a preference or orientation. It is not something I prefer, this is inherent in my humanity. The matter of human sexuality is something to which we are born," she said.

However, the National Marriage Coalition Tempe Harvey, which opposes the recognition of same-sex unions, warned that people engaged in polygamy or in incestuous relationships could demand the same right.

"There's absolutely no reason why you shouldn't open marriage up to incestuous relationships, any consenting relationships, adult relationships, relationships between groups of men, groups of women or whatever.... The line must be drawn," said the groups' head, Tempe Harvey.

The Queensland Parliament is expected to vote on the bill before it breaks for the year.

The state's Labor Party would allow MPs a conscience vote, which is the same policy of Australian Prime Minister and Labor national leader Julia Gillard for a similar measure in the federal Parliament.

MPs for the Liberal National Party were told to follow the party line and vote against the measure.

"I think it will be made a close vote on the simple fact of the dismal exercise by the LNP to enforce political brinkmanship on all their MPs and refuse them to allow to vote with their conscience," Fraser told 9 News.