IT'S one of the No campaign's most potent rallying cries to encourage people to vote against same-sex marriage. The notion that children fare better when brought up by a mum and a dad. Makes sense right?
Well, it seems not. Newly-released research from the University of Melbourne has shot the theory to pieces.
Kids brought up with two mums or two dads fare just as well as those in a family headed by a straight couple, academics concluded.
Indeed, homophobia from others was the real issue for families with gay parents, not the sexuality of the parents themselves,
"The consensus of the peer-reviewed research is that children raised in same-sex parented families do as well emotionally, socially and educationally as children raised by heterosexual couple parents," said the researchers in a paper for the Medical Journal of Australia entitled "The kids are OK".
"These findings have been replicated across independent studies in Australia and internationally,"
However, a spokeswoman for the Coalition for Marriage, the chief No campaign group, said the research was "nothing new" and the studies weren't perfect because they were looking at a "relevantly recent phenomenon."
Despite the proposed change to the Marriage Act making no mention of parenting, and children already being raised by gay mums and dads, No campaigners have attempted to make children the centre of the campaign.
In August, Liberal MP Kevin Andrews, a staunch opponent of same-sex marriage, told Sky News that mum and dad were always best.
"Optimally, you've got the input from both [a mother and a father] and the children brought up in those circumstances, as a cohort, are better off than those who are not.
"Whether it's in terms of health outcomes, mental health, physical health, whether it's in terms of employment prospects, in terms of how this is generated from one generation to another, the social science evidence is overwhelmingly in one direction in this regard," said Mr Andrews.
However, looking at 30 years of analysis of same-sex parenting, the Melbourne researchers led by Professor Frank Oberklaid, found that not to be the case.
Kids raised in same-sex parented families do just as well emotionally, socially and educationally as children raised by heterosexual couples, they said.
The conclusion mirrors similar analysis done in the US.
Earlier this year, Columbia Law School in New York reviewed 79 studies on the wellbeing of children raised by gay parents and found, "an overwhelming scholarly consensus, based on over three decades of peer-reviewed research, that having a gay or lesbian parent does not harm children".
However, prejudice against families with two mums or dads did have a detrimental effect.
The Melbourne research concluded there had been a "damaging misrepresentation" of the evidence on the welfare of children of same-sex couples during the gay marriage debate.
"An increased public health risk exists as a result of homophobic campaign messages for the entire LGBTIQ+ community, including mental health risk for same-sex couples, their children, and young people who identify as LGBTIQ+," the paper said.
The researchers said the few studies which did show children performed poorly when raised by gay or lesbian parents had been criticised for their methodological limitations.
"The entire LGBTIQ+ community is at risk of harm in the current debate around same-sex marriage, and the most vulnerable are children and adolescents," the researchers wrote.
"We have a duty of care to all groups in our society, particularly to those who are vulnerable.
"Our duty extends to calling for public statements based on accurate, objective interpretations of the best available evidence, the correction of inaccurate information, and efforts to reduce the destructiveness of public debate."
A spokeswoman for the Coalition for Marriage told news.com.au: "The article is nothing new; it is just a review of other studies, many of which have been criticised for a lack of random sampling, small sample sizes or other issues. The reality is that no study is perfect because this is a relevantly recent phenomenon."
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