A long-running battle by convicted killer and sex offender, Phillip John Smith, to overturn a ban on sex between prisoners at a sex offenders' treatment unit has been dismissed by the Court of Appeal.
Smith is serving a life sentence for murdering the father of a boy he was sexually abusing.
He made headlines in 2014 for a short-lived escape to Brazil while on temporary release from prison.
In 2022, Smith lost a High Court bid to allow sex between prisoners at the two units for child sex offenders at Rolleston Prison.
At the Court of Appeal in Wellington last month, Smith challenged that decision - but Justices Susan Thomas, Jillian Mallon and Edwin Wylie dismissed it in their judgment released on Thursday.
Smith had submitted that a ban on sex in the two sex offender units at Rolleston Prison was "differential treatment", considering sex was allowed in the general prison population.
But the justices disagreed because entering the treatment units was voluntary.
"... The differential treatment arises not on the basis of a prohibited ground of discrimination, but rather as a result of the voluntary participation in the programmes offered in the units", they wrote.
They also disagreed with Smith's claim the ban discriminated against non-heterosexual men.
In practice, the ban only applied to them as they were more likely to want to engage in sex with other men, he told the court in April.
Again, the justices' decision came down to the fact the rule only applies in the treatment units, which prisoners enter voluntarily.
"Homosexual or bisexual prisoners (or indeed heterosexual prisoners who seek to do so) can engage in homosexual activity while they are part of the general prison muster.
"They lose the ability to do so if they go into the Kia Marama or Totara Units, and, in common with heterosexual prisoners who have not chosen to engage in homosexual activity in prison, they become subject to the prohibition contained in the rule while they are in either unit."
Overall, the prison's ban on sex in those units was justified because it ensured that prisoners could participate in the programmes without distraction, they found.
And it was important to consider the type of people who were in the units, they said.
"As the affidavit evidence before us explains, all of the prisoners participating in the programmes have taken sexual advantage of others.
"Participants have had difficulty managing their sexual preoccupations and they have poor sexual boundaries."
At the Court of Appeal, Smith had argued that just as participation in the treatment programme was voluntary, so too was consenting to abstain from sexual activity.
But the court disagreed, saying people could be coerced into sex.
"On the evidence, many will be manipulative and may engage in patterns of sexual coercion.
"Many will have cognitive impairments. A clear rule is simple and straightforward. It puts in place a 'bright line'."
The court allowed Smith to introduce more evidence by affidavit for it to consider.