· Message to a killer: You picked the wrong family

No scheme can guarantee that sex offenders won’t abuse again and more needs to be known about whether a public register can prevent offending, a top Victorian policeman says.

Victoria Police Deputy Commissioner Graham Ashton said without 24-hour-a-day physical monitoring it is not possible to completely mitigate the risks sex offenders pose to the community.

“It is unrealistic to expect that a registered sex offender is supervised to the point that it is impossible that they find opportunity to reoffend,” Mr Ashton told a conference.

The parents of Queensland schoolboy Daniel Morcombe, who was abducted and murdered by serial child sex offender Brett Peter Cowan, want a public child sex offenders’ register.

Experts at a two-day Asia Pacific Sex Offenders Registry Conference are discussing the idea of a public register but Mr Ashton said the research is incomplete.

“A lot of research tends to focus on the experience of the registrant on the public register – the fact that they feel intimidated in the community by everyone knowing who they are and where they are,” he told reporters on Wednesday.

He said he wanted more victim-focused research on how a public register could prevent offences.

Mr Ashton said whatever model for managing sex offenders is adopted, the focus must be on the protection of potential victims.

“I think some of the crimes that have been impacting on the community, some of the high-profile crimes, have certainly been great learning opportunities for us in terms of how we’re intervening and how heavily we are monitoring,” he said.

There are more than 5300 registered sex offenders living in Victoria alone.

Improved communication between Victoria Police and the Department of Human Services had enabled child protection authorities to act on incidents straight away, Mr Ashton said.

Mr Ashton said social media presents a challenge for authorities, with predators able to prey on victims without ever leaving home.

“Further impacting on the management issues is the increase in social media and other mediums of communication that make it easy for these individuals to contact potential victims, especially the young and the vulnerable, without leaving their premises.”