A hearing to determine what conditions will be placed on the man dubbed the "Beast of Blenheim" after his release from prison has been delayed.

Stewart Murray Wilson, 65, is due to released from prison on September 1.

He was jailed for 21 years in 1996 after being convicted on 22 charges covering rape, stupefying, attempted rape, bestiality, ill treatment of children and indecent assault.

His crimes between 1971 and 1994 involved 16 women and girls who he took into his home on the pretext of friendship and subjected them to cruel and degrading treatment.

Despite attempts by the Corrections Department to keep Wilson behind bars, he could not have an open-ended jail sentence because his sexual convictions predated preventive detention.

A Parole Board spokeswoman said a conditions hearing was due to be held today at Rolleston Prison to determine release conditions for Wilson.

However, Wilson's lawyer, Andrew McKenzie, said the hearing had been delayed as the board required more information.

It was possible the hearing would now be held in August, he said.

The board spokeswoman said the board would be considering information presented by the Probation Service to set conditions for Wilson's release.

The hearing would not look at changing his release date, she said.

The board's decisions were normally released within 10 days, but Wilson's report would be released sooner due to high public interest in the case.

Last month, Corrections Minister Anne Tolley said Wilson would be a candidate for tracking by satellite after his release.

The 24-hour global positioning system monitoring was due to be rolled out from August for 11 child-sex offenders, rising to 200 by next year at a cost of $750,000 this year.

Wilson continually denied his sexual offending, had shown no remorse and reportedly had a limited capacity for empathy.

He had never engaged in psychological treatment and was understood to have refused treatment.

- © Fairfax NZ News