A paedophile already serving preventive detention was jailed again today and the 64-year-old may never be released from prison.

Warren Kenneth Johnston's latest child victim is now a woman in her 40s.

She was in the High Court in Christchurch to tell him about the effects he had on her life and to see him jailed for three years by Justice Graham Lang.

The sentence will effectively lengthen Johnston's preventive detention by a year because it will stop him being considered by the Parole Board for that period.

But he may never be released, even though he has already served 15 years since preventive detention was imposed in the High Court in Wellington in 1997.

He has done the Kia Marama programme for sex offenders twice, during successive jail sentences.

He did not impress with his performance the first time around, soon after the programme began about 1990, and he continued to offend.

He had "a little more success" on a later course, Justice Lang noted, but a psychological report prepared for today's sentencing pointed to continuing difficulties.

He said: "It is clear from the report from the psychologist that you have a considerable way to go before the parole authorities can feel confident in releasing you back into the community. It may be, as your counsel says, that you are never released."

Johnston had admitted offending in Alexandra, Central Otago, in the 1970s and 1980s.

He says he has no recollection of the worst of the offending, which led Justice Lang to say that it "robbed the guilty pleas of the acceptance of full responsibility".

Johnston had admitted two charges of raping a girl aged under 12, and three charges of indecencies with her.

The woman said in her victim-impact statement that she had made her complaints as a result of a breakdown about five years ago.

It had taken many years for her to get over being scared of Johnston.

"I now want to look him in the eye and know I'm not scared of him."

She still slept with the light on, and she still had nightmares.

"Whoever wakes me up from the nightmare has to tell me who they are or I will attack them."

Justice Lang decided against a further preventive detention term, and had to impose a sentence that was in line with sentences imposed at the time. Maximum terms have been increased since this offending.

Prosecutor Kathy Bell said: "He has failed to make any real progress in terms of mitigating his ongoing risk to society. He is still seen to be a significant risk of reoffending if he was released in the near future."

Defence counsel Michael Starling said there was no doubt about the damage Johnston had done through his offending. He said imposing a prison term now would delay his next appearance before the Parole Board.

"It is quite likely he will never be released from prison, but that's a Parole Board decision and not for this court."

He said now that Johnston had been convicted of offending against a girl and boys, his risk would be assessed as even higher.

Johnson first offended sexually with an indecent assault on a boy in 1972 when he was aged 24. This was followed by further convictions in 1982 involving indecencies with boys, a jail term in 1990, and preventive detention in 1997. At that time, the former bus driver from Khandallah was seen as being a member of a paedophile network.

Justice Lang said the sentencing today may be seen as "something of an academic exercise", given the sentence that Johnston was serving, but he said it would be wrong in principle to impose a sentence that effectively imposed no penalty, and he jailed Johnston for three years.

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