Voters reject public funds for plebiscite

As Labor seeks advice on the same-sex marriage plebiscite, a new poll gives the thumbs down on taxpayer funding for the yes and no campaigns.

Bill Shorten says an anti-gay marriage campaign could damage young people unsure of their sexuality. Source: AAP

More than two-thirds of voters reject spending taxpayers' money on the yes and no campaigns for the same-sex marriage plebiscite.

Prime Minister Malcolm Turnbull has announced $15 million would go to the two campaigns, run by committees of MPs and eminent citizens, if the national vote on changing marriage laws goes ahead on February 11.

But an Essential poll published on Tuesday found 68 per cent of voters disapproved of the spending, with only 10 per cent in favour.

Voters are split over whether parliament should make the change, as Labor proposes, or a government-backed $170 million plebiscite should determine the result.

The poll showed 53 per cent support a parliamentary vote, with 29 per cent opposed and 18 per cent undecided.

However, if the plebiscite were to go ahead, 60 per cent said they would vote yes and 30 per cent, no.

Three-quarters of same-sex marriage supporters say parliament should determine the outcome if the plebiscite is blocked in the Senate, as is likely to be the case, while 61 per cent of those who would vote no think there should not be a vote in parliament.

Ahead of the Labor caucus considering on October 11 whether to back the plebiscite-enabling bill, Bill Shorten is consulting with mental health experts and same-sex marriage advocates about their concerns.

Mr Shorten said after a meeting in Melbourne on Tuesday those at the forum had made a "persuasive" argument against the plebiscite.

"The people we've been listening to have explained to us their deep concerns, their persuasive concerns, why this plebiscite is a divisive, expensive and very poor idea in terms of marriage equality," Mr Shorten told reporters.

Meanwhile, coalition backbencher Andrew Hastie warns religious liberty could be limited if same-sex marriage is allowed.

Mr Hastie says marriage is the people's institution and people should have their say on what it means in a plebiscite.

"Changes do not come without consequences," Mr Hastie writes in The Australian on Tuesday.

"Redefining marriage will potentially limit the nature and scope of religious liberty in this country."

Mr Hastie disagrees with coalition colleague Dean Smith, who argues a plebiscite on the matter will undermine parliamentary sovereignty.

"We are not seeking to redefine parliament. We are seeking to redefine marriage," Mr Hastie writes.

"Where Smith invests authority in parliamentary sovereignty, I choose to invest it in the people."