South Australian Premier Jay Weatherill's announcement of a non-binding public vote, no earlier than 2018, on his proposed high-level nuclear waste storage facility looks like an act of political desperation.

It's understandable that Weatherill wants to explore every possible option to replace some of the jobs lost in his state when the Abbott government withdrew support for the car industry.

To that end, he took the unusual step of setting up a Royal Commission to consider South Australia's potential role in the nuclear industry. His appointed Commissioner, Kevin Scarce, faced accusations of pro-nuclear bias.

Scarce's report put a very positive spin on the idea of SA accepting high-level radioactive waste from other countries, suggesting that nations like Japan, South Korea and Taiwan would be willing to pay serious money to make their nuclear waste problems go away.

The local business community embraced the idea enthusiastically, while Adelaide's newspaper, The Advertiser, published a series of articles promoting the scheme, describing the expected economic returns as "gigantic" and running Liberal senator Sean Edwards' claim that nuclear energy would have "no cost apart from the poles and wires".

Citizens' Jury's decisive 2:1 'No!' vote

The way ahead was not straightforward, however, with the community clearly divided. Public meetings convened by those opposed to the proposal saw packed halls, and thousands turned up to a rally outside Parliament House. Indigenous groups are particularly hostile to the prospect of overseas radioactive waste being brought onto their land.

Next, a Citizens' Jury was appointed to offer a verdict on the issue. The randomly selected individuals interrogated experts with a range of views and probed the findings of the Royal Commission in great detail over several days. Their two-thirds majority view that the scheme should be dropped was seen by many as sounding its death knell.

The jury's scepticism is understandable. After deep probing of the estimates, they concluded that the numbers are very rubbery. Moreover, recent examples like the Royal Adelaide Hospital redevelopment do not inspire public confidence in the state government's ability to manage a complex project within a fixed budget.

So the jury decided that the probability of a good financial outcome was not high enough to justify risking billions of dollars of public money developing the waste management system.

It's difficult to know why we need a plebiscite on top of all this. If government members want to know what well-informed members of the public think, they can read the report of their own citizens' jury.

If they want to know what relatively uninformed members of the public think, they can consult opinion polls. And if they want to know what members of the public think after being systematically fed slanted information, they can check the polls conducted by The Advertiser.

Keep on asking until you get the 'right' answer?

The only rational explanation for Weatherill's decision to hold a public vote is that he is hoping for a different outcome.

It's a political tactic with a very notable recent precedent. When it became clear to conservatives in the Abbott government that they had lost the public debate on same-sex marriage, and that a free vote in parliament would probably see it approved, they came up with the idea of holding a national plebiscite.

At the very least, they thought, this would delay the arrival of an outcome they opposed, while there was always the chance that a well-funded, carefully targeted scare campaign might shift the public mood.

But the same-sex marriage plebiscite died when it became clear that it would not be binding on politicians, and that public money would be used to fund the opposing campaigns. Senators sniffed the public wind and voted down the scheme.

Weatherill has invested a lot of political capital in his nuclear waste proposal. He funded the Royal Commission and the Citizens' Jury process. But by pressing the plebiscite button as a way to end the ongoing impasse, he risks running foul of the same problems.

In Canberra, the Senate reflected the general public opinion that a non-binding plebiscite on same-sex marriage would be a waste of taxpayers' money, as well as probably causing an acrimonious and unproductive public debate. One might very well say the same about the idea of a vote on radioactive waste management.

We elect our politicians to decide on policy after studying the issues carefully. It is therefore hard to justify spending millions of dollars on an expensive opinion poll.

If the Citizens' Jury had recommended going ahead with the nuclear waste dump, opponents would have been told to accept its verdict, and stop objecting. It is time for Mr Weatherill to accept the community view and dump the dump!

Ian Lowe is Emeritus Professor, School of Science, Griffith University.

Also on The Ecologist: 'No way! South Australians reject international nuclear waste dump' by Jim Green.

This article was originally published on The Conversation, subject to edits approved by the author. Read the original article.