MPs have resisted public opinion on same-sex marriage for a decade. The reasons are complicated, but new research shows they are gradually being won over

Labor frontbencher and western Sydney MP Tony Burke voted no to legalising same-sex marriage in a parliamentary vote in 2012. He now supports it. Labor’s Jason Clare has admitted he has changed his mind on the issue, and now calls on the Coalition government to “grow a pair” and deal with it in parliament. Liberal minister Josh Frydenberg voted against same-sex marriage five years ago – the party did not give its MPs a conscience vote at the time – but has switched, and now supports allowing same-sex couples to wed.



According to research soon to be published in the Australian Journal of Political Science, not a single politician has flipped the other way – nobody who wanted to legalise same-sex marriage in the failed attempt in 2012 now has doubts. By 2016, almost 60% of Labor MPs who voted no (and were still in in parliament) had shifted to supporting same-sex marriage. Of Coalition MPs, 21% had changed their minds.



The answer's in the post – Australian marriage equality vote explainer Read more

The change has been rapid, but in some ways, so slow. The researchers, Andrea Carson, Shaun Ratcliff and Yannick Dufresne, point out that the issue of same-sex marriage throws up questions about what democracy is: public support for change has been strong in opinion polls for about a decade.



In a representative democracy, politicians don’t automatically vote according to the majority view, but on this issue, the research paper concludes, “federal politicians have largely ignored majority opinion” for complex reasons.



Their analysis of the more than 600,000 responses to the ABC’s Vote Compass survey during the 2013 election campaign, as well data from the Australian Bureau of Statistics, commercial opinion polls and other sources, found that just one electorate – Maranoa, a vast conservative seat in south-western Queensland including towns such as Roma and Kingaroy – opposed same-sex marriage. Just over half its citizens believed marriage should only be between a man and a woman. And its MP, Liberal National David Littleproud, agrees with them.



All other 149 lower house electorates had majority support for change, although some regional seats in Queensland and New South Wales are very tight and only tip over into supportive if undecided voters are included. The electorates of prominent opponents such as Tony Abbott (Warringah in Sydney), Kevin Andrews (Menzies in Melbourne) and Andrew Hastie (Canning in Western Australia) support marriage equality. Warringah, for instance, is one of the most supportive electorates in the country, ranking 14th out of all seats, with about 70% backing marriage equality. Canning is more divided.

Yet here we are. Twenty-three other countries, including New Zealand, Canada, Britain, the United States, Germany and France, have legalised same-sex marriage. And Australia has not.

Here we are, with a government insisting we have a postal survey on this issue, largely because those politicians who want to deny same-sex couples the right to wed have compelled it.

In 2012 the House of Representatives rejected marriage equality by a margin of 98 to 42 – the vote would have been tighter if the Coalition had allowed a conscience vote. The Australian Marriage Equality group says if a vote were held now, it would comfortably pass in both the House and the Senate.



The huge data produced by Vote Compass, with statistical weighting to compensate for a survey that was “opt in”, means that for the first time, we have a glimpse about what people in every electorate thinks and to compare that with their representative’s view. The results give insight into why this issue has been so politically polarising – especially for the conservative parties – and why the national parliament has lagged so far behind public opinion.



It all started in 2004, says Alex Greenwich, an independent NSW state parliamentarian, co-chairman of Australian Marriage Equality and a gay man who married his partner Victor in Argentina five years ago, a marriage that is not recognised in Australia.



Facebook Twitter Pinterest John Howard and attorney general Philip Ruddock in 2004, when the prime minister announced the Marriage Act will be amended to exclude gay couples and ban same-sex couples from adopting children. Photograph: Alan Porritt/AAP

It was then prime minister John Howard’s insistence that the Marriage Act be amended to specify that marriage was “the union of a man and a woman to the exclusion of all others”, that spurred Greenwich, now 36, to become actively involved in changing the law.



Because the right has made it so central to the culture wars …it has become a totemic issue Dennis Altman

Australian Marriage Equality, a nonpartisan group that campaigns for same-sex marriage, was established that year. “My initial support was based around the fact that I don’t like being told I can’t do something because I’m gay, especially to marry the person you love,” Greenwich says.

Labor backed Howard’s amendment, reluctantly. “Labor has made clear we don’t support gay marriage,” said frontbencher Nicola Roxon at the time. It wasn’t until 2011 that Labor’s policy platform was amended to support marriage equality. The Greens have always backed it.



Dennis Altman, academic and pioneering gay activist, agrees with Greenwich that Howard’s attempt to delegitimise the marriage of gays who had travelled overseas to wed was the catalyst for a determined campaign to change the law.



“It really only became an issue after John Howard made it an issue,” says Altman. “More radical people never saw the importance of marriage, but over the last couple of years because the right has made it so central to the culture wars and have linked it to so many other issues, it has become a totemic issue.”



The first public poll on same-sex marriage in Australia is believed to be a Newspoll in June 2004. That found that 38% of respondents were in favour of same-sex marriage and 44% against. Just three years later, opinion polls started to find majority support – Greenwich puts that down to active campaigning by LGBTI groups and the influence of more overseas countries changing their laws.



The latest Newspoll in August found 62% in favour, with 32% against and 6% uncommitted.

Essential Media has just released a report summarising all its polling on marriage equality since 2010. It showed that support has steadily increased from the low 50s in 2010 to tdeche low 60s now, with most Australians expecting the laws to change in the next few years.

Research director Andrew Bunn says the only comparable issue where public opinion has been so out of step with political opinion is assisted dying, where an even higher percentage of people support allowing a terminally ill person assistance to die if they choose.

Carson says the research paper, Same-sex marriage debate in Australia: Public opinion and policy congruence, is the first empirical research in this country into legislators’ policy responsiveness to public opinion.

Although national opinion is strongly in favour of change, it becomes more complex – particularly for the conservative parties – the more you drill down.

“Opposition to same-sex marriage was highest in 2013 in divisions with fewer same-sex couples; a higher average Coalition two-party vote across the 2010 and 2013 elections; lower median ages (suggesting a higher number of families with children); lower household incomes; lower population densities, and a greater proportion of overseas-born residents,” the research paper says.

In other words: “Electorates with high levels of opposition to same-sex marriage tend to provide the Coalition with the majority of their two-party vote. Those with lower levels of opposition were more likely to vote Labor.”

There needs to be overwhelming support before their MPs are prepared to move away from the status quo bias Andrea Carson

It isn’t hard to see why the Coalition has been so divided on this – much of its support, particularly in country areas and among older voters and people with strong religious affiliations, have reservations, although they have declined over time.

Labor has also been torn in the past, because of its (declining) links to the Catholic church and because immigrants who support the ALP are more likely to be conservative on this issue. Jason Clare’s electorate of Blaxland in western Sydney is among the 10 seats with the highest resistance to same-sex marriage. More than 60% of its people speak a language other than English at home and more than 20% identify as Muslim, making them less likely to be pro marriage equality.

Many Coalition members – but not all – have responded to their electorates’ comparative unease. Of the 10 seats where objection to marriage equality is strongest, only one is represented by an MP who is a definite supporter – Jason Clare.

Of the 10 electorates with the highest backing for marriage equality (in some seats support is around 90%) every MP approves of same-sex marriage and will vote to change the law, whether the politician is Liberal or Labor.

Facebook Twitter Pinterest Alex Greenwich, Joyce Maynge and Sydney councillor Linda Scott at a charity run for Mardi Gras. Photograph: Mark Kolbe/Getty Images

Carson says there is a “status quo bias” in Australia – a temptation to leave things as they are – and that majority approval of same-sex marriage has not been enough for MPs to be convinced.

Our major political parties are “interest aggregators” – interest groups such as religious organisations influence political parties on specific issues because they can be relied upon at elections, whatever the general voter might think.



“Some of those groups, even though they are a minority, are quite vocal within political parties, which can’t afford to ignore them,” says Carson, a lecturer in political science at the University of Melbourne.



“With Labor, most of the MPs have moved to support same-sex marriage. We find there needs to be a certain tipping point before they will shift over and that’s well above the 50% mark. It needs to be up to the 60% range before you start seeing MPs shift. It needs to be much higher (on average) for Coalition MPs. There needs to be overwhelming support before their MPs are prepared to move away from the status quo bias.”



The research found that MPs representing electorates where opposition to same-sex marriage was 40% – so well below half – would still tend to resist change. There was still a 95% chance that they would be against same-sex marriage.



Facebook Twitter Pinterest Liberal minister Kelly O’Dwyer, right, represents a constituency, Higgins, where voters overwhelmingly support equal marriage, according to polling evidence. Photograph: Mike Bowers/The Guardian

“It was only once same-sex marriage opposition declined below an estimated 30% … did the probability of a Coalition MP opposing changes to marriage laws drop below 50%, and then only by a small margin.”



That explains why many Coalition MPs in big cities representing more educated, more affluent electorates such as prime minister Malcolm Turnbull in the Sydney seat of Wentworth and Kelly O’Dwyer in the Melbourne seat of Higgins, have no resistance to supporting same-sex marriage. Both of those electorates are in the 10 that most strongly support marriage equality, so there is no political risk for their MPs.



The other issue is “salience” – people might support marriage equality, but are unlikely to change their vote on it. It was not among the most critical issues for the Vote Compass responders. The Essential report notes that in a 2010 opinion poll, 60% of people did not think it was an important issue compared with others such as the economy and healthcare. (A majority of Green voters did think it was important.)



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Given the heat over same-sex marriage now, the importance of the issue to voters may have changed. Essential found that those who opposed marriage equality felt more strongly about the issue than those who supported it. This was particularly true for Liberal and National voters, where 48% of those opposed feel very strongly compared with only 16% of those in favour.

Carson says her study indicates that same-sex marriage will happen in Australia. “It’s going to be inevitable given that public opinion is slowly overwhelming this status quo bias, but we don’t know when,” she says. “Even within the Coalition, their levels of opposition have fallen over the last four years, which suggest that their MPs are reading the signs.”

It has taken a long time to read the signs, but all the signs are all there.

Ten electorates most opposed to same-sex marriage Maranoa*, Queensland (represented by LNP’s David Littleproud – voting no)



Groom Queensland (represented by LNP’S John McVeigh – voting no)



Flynn, Queensland (represented by LNP’s Ken O’Dowd – voting no)



Hinkler, Queensland (represented by LNP’s, Keith Pitt – voting no)



New England, New South Wales (represented by National Barnaby Joyce – voting no)



Kennedy, Queensland (represented by Katter’s Australian party’s Bob Katter – voting no)



Grey, South Australia (represented by Liberal Rowan Ramsey – voting intention unknown)



Blaxland, NSW (represented by Labor's Jason Clare – voting yes)

Barker, SA (represented by Liberal Tony Pasin – voting intention unknown)



Parkes, NSW (represented by National Mark Coulton – voting intention unknown) * Only seat where a majority was opposed Source: Same-sex marriage debate in Australia: Public opinion and policy congruence, UNSW

Ten electorates most supportive of same-sex marriage Sydney, NSW (represented by Labor Tanya Plibersek – voting yes)



Melbourne, Victoria (represented by Greens’ Adam Bandt – voting yes)



Grayndler, NSW (represented by Labor’s Anthony Albanese – voting yes)



Wentworth, NSW (represented by Liberal Malcolm Turnbull – voting yes)



Melbourne Ports, Victoria (represented by Labor’s Michael Danby – voting yes)



Wills, Victoria (represented by Labor’s Peter Khalil – voting yes)



Gellibrand, Victoria (represented by Labor’s Tim Watts – voting yes)



Batman, Victoria (represented by Labor’s David Feeney – voting yes)



Higgins, Victoria (represented by Liberal Kelly O’Dwyer – voting yes)



Brisbane, Queensland (represented by Liberal Trevor Evans – voting yes) Source: Same-sex marriage debate in Australia: Public opinion and policy congruence, UNSW