CANBERRA -- The High Court's political dance card is getting busy.
Marriage equality advocates and independent federal MP Andrew Wilkie are filing a constitutional challenge against the same-sex marriage postal vote, charging that both the Turnbull Government and the agency it wants to run it are exceeding their authority.
As a litigant, Wilkie is joined by Victorian mother Felicity Marlowe and Parents, Families and Friends of Lesbians and Gays (PFLAG) spokesperson Shelley Argent.
All are supporters of a free parliamentary vote on marriage equality.
A group, backed by longtime marriage equality campaigner Rodney Croome and with legal backing from barrister Ron Merkel QC, will file papers for a High Court challenge late on Wednesday or early Thursday. Other potential challengers are being urged to join them.
The High Court has already been asked to look at the validity of the elections of Larissa Waters, Scott Ludlam, Matt Canavan and, soon, Malcolm Roberts.
The effort appears to be at least partially funded by crowd-sourcing. The litigants told reporters in Canberra that any cost would be worth it.
"We'll be filing in the High Court to have the High Court strike down the postal plebiscite in the hope that we can then proceed to the resolution of this issue in a way that should always have been dealt with, and that is, a free vote in parliament," Croome said.
Earlier the Senate voted to effectively kill off the original plebiscite enabling legislation by tying an unusual vote to 'restore' it for debate, 31-to-31. This pushes Australia towards a $122 million voluntary, legally questionable postal plebiscite run by the Australia Bureau of Statistics, the agency responsible for #CensusFail.
A "yes" vote in the postal vote, according to the Prime Minister, will be followed by a free vote based on a private members' bill to legalise same-sex marriage. A "no" vote will not.
The litigants reject a postal vote as voluntary, non-binding, non-representative, particularly for young people and likely to generate fear-mongering and hatred during the campaigning.
— Matthew Doran (@MattDoran91) August 9, 2017
Both moves, towards a postal vote and a legal challenge, were expected.
The Government, including the Prime Minister, have stated confidence that a postal vote will withstand a High Court challenge.
Croome advises the High Court challenge is based on constitutional question marks surrounding the government's decision to use a special allocation of money and the ABS, not the Australia Electoral Commission (AEC), to hold the postal plebiscite.
"The problem of the government exceeding its executive authority continues to be an issue with this new proposal," Croome said, adding Merkel's advice is that the government needs legislation to back up a postal vote.
— HuffPost Australia (@HuffPostAU) August 9, 2017
"Mr Merkel also feels that the idea of a postal vote running through the ABS may exceed the ABS's authority," he said.
"Particularly when we consider whether a postal vote on marriage equality is statistic gathering or not. He thinks there would be question marks over whether that is in fact the case."
Andrew Wilkie said he was looking forward to his day in court. The MP said the case, for him, was about governance.
"It is truly frightening that the government thinks it is OK to exceed its powers like this and to bypass the parliament, " Wilkie said.
"It is not OK for the government to think it is a law unto itself and that it can bypass the parliament."
Australians are expected to start voting in five weeks with mailed ballots expected to arrive in letterboxes from mid-September, but the timing now depends on this and any other legal challenges.