In a piece of political sleight of hand, PM Malcolm Turnbull has turned what should have been a straightforward conscience vote into an expensive and deeply divisive public vote.

Make no mistake, this plebiscite is a Trojan horse, a way for Mr Turnbull to appease the conservative fringes of his party and neatly abrogate the parliament’s responsibility to make a polarising decision.

And it will cost a bundle.

PriceWaterhouseCoopers has estimated the plebiscite could cost the taxpayer more than half a billion dollars all-up.

The deeper cost can’t be measured in dollars.

It can measured in the emotional damage to those whose fundamental human rights are being debated.

Labor leader Bill Shorten’s suggestion on Tuesday the debate could trigger a rash of suicides might be a touch hyperbolic, but there’s little doubt the gay community will be subjected to months of false and belittling commentary.

The propaganda, of course, will come from both sides.

But those who have already been vilified for their sexuality, and who have the greatest personal stake in the debate, will be hardest hit.

Even before a plebiscite was announced, the campaign of vitriol had begun. Leaked pamphlets authorised by former Liberal MP Chris Miles claimed that "social outcomes" for children of same-sex parents were "unemployment", "sexually transmitted diseases" and "drug use/abuse". This flies in the face of the bulk of scientific research. 

Expect the upcoming plebiscite debate to be dominated by opinion over fact and provide a platform for vocal bigotry.

The views of those that oppose gay marriage – and many in our region do – are as valid as those that support it. But that in itself doesn’t validate the need for a plebiscite.

Most people, regardless of their political persuasion, accept love cannot be defined by gender boundaries. So why should the ultimate expression of love’s commitment – marriage – be?

If we accept some people are born gay, what right do politicians have to say the love they feel is illegitimate?

It’s human to be afraid of the unknown. But it’s just as human to show compassion.