AUSTRALIANS will get the chance to have their say on same-sex marriage with the High Court ruling the Government can spend $122 million of taxpayers' money on a controversial postal survey.
Ballots with the question, "Should the law be changed to allow same-sex couples to marry?" will be sent to households across the nation on September 12.
Following the High Court decision, Prime Minister Malcolm Turnbull told Question Time that "Lucy and I will be voting yes and I will be encouraging others to vote yes." Opposition Leader Bill Shorten tweeted "Let's win this."
Activist group GetUp said the Government had been "sneaky" in circumnavigating Parliament but the vote could be "the biggest own goal the Liberal party have ever seen."
But Lyle Shelton of the Australian Christian Lobby, one of the main groups against same-sex marriage, has said the vote will be a "referendum on freedoms and radical sex education in schools".
If a majority of people vote in favour, a vote will then be held in parliament which Turnbull says he expects will make same-sex marriage legal. If Australians vote no, Mr Turnbull has said the parliamentary vote will not proceed.
Campaigns by both the yes and no campaigns have kicked off immediately. The yes side has released a television ad campaign featuring Olympian Ian Thorpe with the catch cry "it's about a fair go". The anti side were reportedly handing out cards directing people to vote no outside the High Court.
The Government funded the multi-million survey using laws which allowed the spending if there was an urgent need and the situation was unforeseen.
Same-sex marriage advocates had argued the survey was neither urgent nor unforeseen and the Government could not spend the funds without parliamentary approval, which it would be unlikely to get.
But the High Court ruled that was not the case, effectively giving the green light to the poll.
Mr Turnbull was convinced the postal vote wouldn't be stopped by the court.
Sally Rugg the Marriage Equality Director of GetUp said LGBTI Australians would be "reeling" following the High Court's decision.
"It's clear the government have done their homework and have managed to sneakily circumvent parliament to force this postal vote on us.
"This isn't where we wanted to be - and we're only here because Tony Abbott is still calling the shots in this government - but the government have another thing coming if they think we're not prepared to win.
"We're about to make the postal vote on marriage equality the biggest own goal the Liberal party have ever seen," she said.
Talking to news.com.au earlier on Thursday, Equality Campaign head Tiernan Brady explained why those in favour of same-sex marriage were opposed to a plebiscite.
"Australia's parliament is where decisions about laws are taken and if we take one group of people and say your rights have to go through a tougher process before you get to Parliament that's an unfair process," he said.
But with the tick having been given to the survey it was full steam ahead, Mr Brady said.
"We're in it to win it. We know that the Australian people are for [SSM] and we'll do everything we can to ensure those values reflected in the result," he said.
It emerged on Thursday that $14.1 million dollars had already been spent on the survey for an advertising campaign encouraging Australian to check their details on the electoral roll and on printing the ballot papers and envelopes.
In late August, the Australian Electoral Commission said 90,000 people had joined the electoral roll ahead of the same-sex marriage postal vote with almost a million Australians checking their details.
Unlike usual votes, the postal survey is voluntary. Forms need to be returned by early November but yes campaigners have predicted 80 per cent of forms could be sent back by the end of next week.
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