Labor has challenged Home Affairs Minister Peter Dutton to prove a national online register of child sex offenders will be effective after some experts criticised the plan.
Under the federal government's proposal, the register would contain information including the person's name, photograph, aliases, date of birth, nature of offending and their general locality, such as their postcode.
Home Affairs Minister Peter Dutton said a register was one part of a "jigsaw puzzle" in protecting children but cautioned against viewing it as a "silver bullet".
"If it saves one child, if it prevents one child from falling prey to a pedophile in our community, then it's worth pursuing," he said.
Shadow attorney-general Mark Dreyfus wants the minister to guarantee the register would not compromise the existing registration system or make it harder for police to do their job.
"When this was raised a few years ago, then-prime minister Abbott rejected it as not being effective. It would be good to know what has changed since then," Mr Dreyfus said.
Two reviews of a similar register started in the United States in 1996 found little evidence it had impacted on sex offending, according to a 2007 Australian Institute of Criminology report.
Cathy Kezelman, the president of child trauma support organisation Blue Knott Foundation, said the jury was out on whether it was appropriate for all offenders to be on a public register.
"The research and international experience shows at best it does nothing and at worse it may actually make people more likely to reoffend," Dr Kezelman told Sky News.
But parents of Daniel Morcombe - a 13-year-old abducted and murdered on the Sunshine Coast in 2003 by a man who had been jailed twice for molesting young boys - back the plan.
Bravehearts chair Hetty Johnston said a register would not have saved Daniel, arguing governments should keep child sex offenders behind bars.
Independent senator Derryn Hinch has long advocated for a national public register of offenders and was delighted with Mr Dutton's announcement.
"I can die happy; this is the only reason I got into politics," Senator Hinch said.
Mr Dreyfus said the existing nationwide register available to police and working with children checks were both effective measures.
Australian Associated Press