Justice Richard Button on Tuesday instead imposed a five-year extended supervision order with stringent conditions on Michael Guider.

The now 68-year-old pleaded guilty in 2002 to the manslaughter of nine-year-old Samantha, who went missing after leaving her Bondi home for school on August 19, 1986. Her body has never been found.

His 17-year jail term has expired, but he was placed on an interim detention order which expires on Thursday.

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The NSW Attorney-General had made a Supreme Court application for a one-year detention order.

When sentenced for Samantha's death, Guider was already serving time for numerous sex offences against more than a dozen other children between 1980 and 1996.

The judge said the hearing was to assess the risk Guider posed in the future, rather than imposing punishment for his prior offending.

He found that a further period of incarceration would not serve any rehabilitative purpose.

While it could not be said definitively that Guider's sexual interest in children had disappeared, the judge considered he had done all that could be done in terms of rehabilitation in a prison setting.

Three experts, highly experienced in psychology and psychiatry, had all agreed Guider's risk could be reasonably managed under a stringent and lengthy system of supervision within the community, the judge said.

He had taken note of Guider's good behaviour when he was on escorted day leave from jail.

AAP