The warning was issued after an eBay listing for a postal vote appeared on the site yesterday with a price tag of $1,500 AUD (€1,000).

The listing, titled ‘Buy my Vote’ which has since been removed, read: ‘What is this plebiscite worth to you. The reason I’m selling my vote is because either way I don’t care but thought there are people who do.’

The charitable seller goes on to add that part of the auction’s proceeds “will go to help kids battling cancer.”

ABC reports that the Australian Bureau of Statistics has initiated discussions with other online auction sites, including eBay, Facebook, Amazon, Alibaba and Gumtree, in an attempt to stop people from selling their surveys.

“To date, eBay and Facebook have confirmed listing survey forms or survey responses for sale would not comply with their policies and they will block and remove any such listings,” an ABS spokesman said in a statement.

“The ABS considers the submission of any Marriage Law Postal Survey Form with a response that has been bought or sold would likely be an offence against the Census and Statistics Act 1905 or the Commonwealth Criminal Code.”

Australians found selling their votes could be fined up to $2,100 AUD and face a maximum penalty of 12 months’ imprisonment.

“What do you think you’re doing?” said former GLEN policy director Tiernan Brady, now campaign executive director for Australians for Equality after news of the eBay listing was reported. “This is a serious discussion about real people’s lives.”

More than 16 million survey forms will be sent to eligible voters’ households from September 12, following the dismissal of a High Court challenge this week. Australian voters will be encouraged to return them by October 27, with a deadline of November 7. The results will be released at 11.30am, November 15.