Wayne Wilmot was sentenced to a one-year continuing detention order in the NSW Supreme Court on Thursday to prevent the high-risk offender leaving custody.
Wilmot was one of five homeless youths involved in the abduction and rape of bank teller Janine Balding in 1988, a case that garnered national attention.
The 20-year-old bank teller was repeatedly gang raped before being bound, gagged and held underwater in a dam until she drowned.
Wilmot, who was 15 at the time, was found not to have taken part in the murder but was sentenced to eight years in prison over the abduction and rape.
But his involvement in the attack on Ms Balding was neither the first nor last offence Wilmot was found to have committed.
A previous court ruling found Wilmot had a history of violent sexual offending dating back to when he was 13 years old and included several offences while in custody.
After being released on parole in 1996, Wilmot robbed one female victim and assaulted another.
In 2024, Wilmot was returned to jail just 11 days after being released for breaching a condition of his supervision order preventing him from accessing pornography.
With that sentence due to expire, Justice Sarah McNaughton determined on Thursday it was in the community's best interests that Wilmot remain in jail for at least another year.
"I am satisfied to a high degree of probability that the defendant poses an unacceptable risk of committing another serious offence of a sexual nature if not kept in detention," she said.
The court has previously found Wilmot had a highly disruptive home life in childhood and suffered multiple instances of sexual and physical abuse, leaving him unable to maintain a stable life.
Psychological assessments conducted on Wilmot in 2019 found he had an IQ of 74 - placing him at the fifth percentile - and was highly callous, manipulative and deceptive, consistent with psychopathy.
He has spent less than two years out of custody since the age of 15.
Justice McNaughton's continuing detention order will expire on March 19, 2027.
The maximum length of an order is five years.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
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