Anti-abortion groups insist a visit by a controversial American activist criticised for advocating executions of abortionists will be peaceful.
Right To Life Australia has invited campaigner Troy Newman on a series of speaking events across the country from October 3.
Newman, who wrote a book calling for the execution of doctors who perform abortions, plans to discuss "the sale of body parts from aborted babies at Planned Parenthood clinics in the US".
The opposition is urging Immigration Minister Peter Dutton to refuse Mr Newman a visa over concerns he will incite community harm and harassment of women at medical clinics.
Labor MP Terri Butler says it's up to Mr Dutton to prevent a repeat of events in 2001, when anti-abortionist Peter Knight murdered a security guard at a Melbourne medical facility.
"It is not hard to imagine that Mr Newman's call for abortionists to be executed could lead to threats or the commission of acts of violence against women and medical professionals," she said in a statement on Tuesday.
But Right To Life says blocking Mr Newman would stifle free speech, accusing "some women of the ALP" of being in favour of killing unborn babies.
Right To Life CEO Katrina Haller said it was ridiculous to presume the visit would incite violence, arguing the group advocated non-violent means of protesting.
"He only wants to save the babies and help the mothers," she told AAP.
"It will be very peaceful and very positive."
Mr Newman planned to expose the "house of horrors" of abortion clinics and how Australia could learn from the legislative successes of some US anti-abortion campaigners.
Asked if she agreed with some of Mr Newman's controversial comments, Ms Haller said the group agreed abortionists were murderers.
But she also pointed to Mr Newman's Operation Rescue group in 2009 denouncing the killing of abortionist George Tiller.
Comment has been sought from Mr Dutton.
