A repeat sex offender who kidnapped a woman from a supermarket carpark and raped her has been sentenced to preventive detention.

Robert Allen Mair, 40, told police he sexually violated the 19-year-old to make his ex-partner angry.

Mair appeared in the High Court at Palmerston North this morning for sentencing, where Justice Christine Grice laid out the details of the offending.

Mair had been on a sentence of home detention, but cut off his monitoring bracelet and went in search of his ex-partner on November 27 last year. She had ended the relationship with him a few days earlier.


He found her and their children at a hotel in Whanganui, but "police arrived soon after and took her to safety".

Mair then approached a woman in her car, got into the passenger seat while holding a knife, and told her to drive.

But when the woman screamed no and jumped out of the car, Mair fled.

About 15 minutes later, he found another young woman sitting in her car at a supermarket carpark.

"You held your knife towards her telling her to shut up."

He forced the woman to drive for a while, telling her he only wanted the car and was not a rapist.

He then took over driving, forcing the woman into the footwell of the passenger seat.

She tried to escape the moving vehicle, but Mair pulled her back in. He then stopped and told her she would have to perform a sex act on him for trying to escape.

When the woman confronted him with his statement that he was not a rapist, he forced her into the boot of the car and continued driving.

When stopping for petrol, he told the woman he would kill her and another person if she tried to get away again.

"She was afraid for the welfare of the petrol station attendant and bravely decided to stay," Justice Grice said.

After continuing on to a secluded spot, Mair sexually violated the victim, raped her, and forced her to perform sex acts on him.

He told her she had two choices: do what he said, or die.

Mair eventually let the woman go, and was found by police the next day.

He told officers he sexual violated her to anger his ex-partner.

The victim recorded her impact statement ahead of the sentencing and had it played on DVD in court, as she did not want to be in the same room as Mair.

She said she did not want to be in her own body after the offending.

Since the attack, she has been anxious and paranoid, unable to work, and fears covered carparks. She has flashbacks to the day it happened.

"I aways feel self conscious that it's written all over me.

"I keep asking myself, why me?"

Crown prosecutor Michael Blaschke said the victim "acted out of self preservation".

She "displayed incredible bravery in the way she looked after herself as best she could that day", he said.

Blaschke said the offending was "highly premeditated and planned".

The Crown's position was that the safety of the community "requires the defendant to remain in custody until he is assessed as safe for release".

Defence lawyer Esme Killeen said Mair had a "sad story" behind him, and was struggling to understand how he had reached this point.

"He is really, really ashamed to be back before the court," she said.

Mair tried to plead guilty at his first appearance and had wanted to participate in Restorative Justice, but had not been able to. He has also written an apology letter, Killeen said.

"It is an utter tragedy that he has reoffended in this way . . . he is a man capable of change, he is a man that is motivated to make a better life for his own children than he himself had."

Justice Grice said Mair had 33 previous convictions, eight of which were for sexual offending, and two of which were for kidnapping.

"There are four women whose lives have been destroyed by you," she said.

He has pleaded guilty on this occasion to two counts of sexual violation, one count of sexual violation by rape, one charge of kidnapping, and one of attempted kidnapping.

"Your offending seems to be perpetuated by hostility toward women."

When rejected, Mair would visualise taking revenge in a way that made his victims feel as powerless as he did, Justice Grice said.

Justice Grice gave him a warning under the three strikes law, and sentenced him to preventive detention with a minimum period of imprisonment of six years and seven months.