Shadow attorney-general Mark Dreyfus says the Opposition will vote against the “many dozens” of amendments to Liberal senator Dean Smith’s legislation, except some technical tweaks to be proposed by the government.

Among those seeking changes are Liberal senators James Paterson and David Fawcett, who want to include two definitions of marriage – one as between a man and a woman and one as between two people.

“Labor will be opposing all of the substantive amendments that are being proposed,” Dreyfus told reporters in Canberra today.

“We do so with the very clear intention that we need to get this done. It’s not a time for concentrating on issues that have got little or nothing to do with achieving marriage equality in Australia.”

Many of the amendments moved away from equality and increased discrimination on a bill aimed at achieving the opposite, he said.

Changes that propose detailed religious freedoms would pre-empt an inquiry led by former attorney-general and human rights envoy Philip Ruddock on the issue.

Several Labor senators have expressed support for greater religious protections, but none sought a conscience vote on any of the amendments that have so far been put forward.

“The likelihood that some of these issues can be addressed within the limited time frame of this week leaves us with reservations about a number of the amendments as they are currently before us,” Labor’s Jacinta Collins, who will be voting against the final bill, told parliament.

Labor has given its members a free vote on the issue of same-sex marriage.

“I hope and believe that a majority of senators respect the will of the Australian people and will approach amendments with that intent in mind,” Opposition Senate leader Penny Wong told reporters.

“Obviously, there are some Labor senators who have a different view on the issue of marriage equality and they have been very honourable and collective in the way they’ve approached these issues.”

Crossbencher David Leyonhjelm doesn’t think the twin definition proposal will succeed.

“I don’t like its chances of success. It’s making life very complicated,” he told reporters.

Meanwhile, One Nation leader Pauline Hanson has warned polygamy and underage marriage could be among the unintended consequences of legalising same-sex marriage.

Despite raising concerns, the One Nation leader said she is still unsure whether she will support the bill before the Senate and will give her party colleagues a free vote on the issue.

“My concern is that, in time to come, the parliament and its members could at any time change this (definition) to include multiple marriages or marriages of people under a certain age,” Hanson told parliament today.

Hanson will move an amendment to the bill to protect civil celebrants who want the right to refuse to marry gay couples.

“I don’t believe we are fully aware of the ramifications this is going to have on our society,” she said.

She believes there should have been a referendum to define the meaning of marriage in the constitution, rather than the voluntary postal survey that returned a 61.6 per cent ‘yes’ vote.

Hanson used the 1967 referendum over recognising indigenous Australians as an example of a change which had created unintended consequences like “reverse racism”.

“We have now made laws that give Aboriginals more rights than other Australians,” Hanson said.

“They are treated totally different under the law. People did not vote for that, hence my concerns about this plebiscite.”

– AAP