Greens senator Robert Simms has ripped into former prime minister Tony Abbott for speaking to an ultra-conservative anti-gay group in the U.S. last week.
In a speech to the senate late on Tuesday, Simms said the agenda of the Alliance Defending Freedom (ADF) was "life-destroying".
"It advocates for the criminalisation of homosexuality and the abolition of anti-discrimination laws that protect the rights of LGBTI people," he said. "It is a lunatic fringe organisation that promotes an agenda that ruins people’s lives."
"[Abbott] is a former prime minister of this country... With that in mind, he should think very carefully about the causes with which he associates."
According to a 2013 report from the Southern Poverty Law Centre, the ADF offered assistance to an anti-gay group in Belize to stop a law against homosexual sex, carrying a prison sentence of 10 years, from being overturned.
"My home state of South Australia abolished [laws against gay sex] 40 years ago last year, but that’s the kind of world this organisation wants to take us back to," Simms said. "With all the heartache and human misery that comes with that."
In his address to the ADF on Friday last week, Abbott said same-sex marriage was "an ask too far" from the gay community.
"Not long ago, most gay activists rejected marriage as an oppressive institution," Abbott said.
"Now, they demand as their right what they recently scorned; they demand what was unimaginable in all previous times and still is in most places."
Abbott also delivered a plea for people debating family "to place ourselves in others’ shoes and to keep conversation civil".
However, Simms said Abbott should "take his own advice" on injecting common sense into the marriage debate.
"Let’s face it, this is a politician who is so conservative he makes John Howard look like Karl Marx," Simms said. "It’s time for him to put his ideology aside and stop fanning the flames of division in our country."
He likened the ADF to "the Australian Christian Lobby on steroids when it comes to demonising innocent people".
"What’s next, what’s planned for his next US visit, a press conference with Donald Trump perhaps? They certainly seem to be promoting the same brand of ugly divisive politics."
Simms also took aim at prime minister Malcolm Turnbull, who said last week that Abbott had the right to speak to any group he pleases.
"He needs to call Tony Abbott out for his bigotry," said Simms. "What does this say about the government of our country when you have one of its key figures behaving in this manner?"