"Gay panic" should not be an excuse for murder, but in two Australian states it still is.

Eight years ago Wayne Ruks was bashed to death by two men in the courtyard of a Maryborough church while he was walking to the local shops.

At the time his killers were charged with murder but were convicted of manslaughter after their lawyer argued the so-called “gay panic” defence.

In 2008, only four years into a nine year sentence, one of men walked free, while the other will be considered for parole in a few months.

“They just left him there to die,” his mother Joyce Kujala says.

The ‘gay panic’ defence means a man can get away with murder if he says another man came onto him and, as archaic as it sounds, it’s still the law in Queensland and South Australia.

“‘Gay panic’ is a law that can get anybody out of murder, there’s not doubt about it,” she said.

Kujala, who also said her son had a girlfriend of ten years, believes it was simply used to lighten the sentence of his killers.

She also said CCTV footage proved Ruks made no physical advances on the men who killed him.

Regardless, she labelled the law “nonsense”.

Comedian Tom Ballard agrees and is urging people to back a campaign by Catholic bishop to have the law changed.

"The murder of a gay man is a lesser crime if we do what we all do, all the time and flirt with somebody," he explains in a video released to coincide with International Day Against Homophobia today.

Watch Ballard's full spiel on "gay panic" here (post continues after video):

As a gay man, Ballard explains he's had some uncomfortable interactions with straight men over the years but observes the correct response is to have an awkward laugh about it and move on, not to kill someone.

"If any of those straight men were to be so offended by my advances that they proceeded to stab me multiple times and then dump my body in a wheelie bin, I’d like to think the justice system would prosecute them to the full extent of the law," he said.

He's urging Australians to sign a Change.org petition to have the law changed -- and more than a quarter of a million already have.

Fr Kelly said it's disgraceful such a law still exists, let alone that it was used just last month to grant a retrial to Michael Joseph Lindsay who was jailed for 23 years after repeatedly hitting and stabbing a man in 2011.

"Australia is an international disgrace for still having this homophobic law on its books," he said.

While the Queensland state government claims to be "working on it", Fr Kelly said he's heard nothing on the issue from the South Australian premier Jay Weatherill.

"Every day, every hour that passes, another killer could walk free because of this outdated law.

"And it’s a demeaning, dangerous insult to gay people."

You can read the petition here.