Killer Nathan Boulter investigated four years ago for rape allegations when he was 14

Warning: This story contains content some may find disturbing.

Convicted killer Nathan Boulter was investigated four years ago over an allegation he raped a 15-year-old girl when he was 14.

He was spoken to while serving time in Otago prison where he denied any wrongdoing, and said the sex between the two was not rape and that the woman was his girlfriend at the time.

Police said after reviewing all the available evidence, the matter did not reach the threshold to prosecute under the Solicitor-General Prosecution Guidelines.

Boulter - who had a long history of stalking and assaulting ex-partners - pleaded guilty last week to murdering a woman in Parklands, Christchurch, on 23 July.

The woman had been in a brief relationship with Boulter. After she ended it, he harassed, stalked and threatened her, making nearly 600 calls in two weeks, before hiding outside her home, then stabbing her 55 times with a hunting knife, as she arrived home with her children.

It can now be revealed a woman went to police in 2021 with allegations that she had been raped and physically assaulted by Boulter while they were at Aparima College in Riverton in 2003.

A police report form detailing the allegations, seen by RNZ, said police investigated two allegations of historical sexual assault and one allegation of physical assault made by the woman.

Do you know more? Email sam.sherwood@rnz.co.nz

The report said Boulter had "numerous convictions" and referred to his "violent offending" making national headlines.

In April 2021, the woman, then aged 32, went to the Hamilton Central Police Station with her partner to report a sexual assault.

During a preliminary interview she alleged she had been raped by Boulter on two occasions and was physically assaulted by him on one occasion.

The alleged attacks occurred over a one-two week period when she was 15 and he was 14.

"[The woman] stated that she had seen something in the media where Boulter's adult offending was reported on and this has triggered an emotional response from her," the police report said.

"She thought it was best to now report what happened to her as a young person as the offending had caused ongoing psychological damage."

The report also said that when talking about the sexual assaults the woman's position was "she only went along with it as she was fearful, felt coerced and was subject to Boulter's control and pressure".

The woman was formally interviewed by police a week later where she detailed the three incidents.

She described feeling "fearful, scared, and terrified" during the first incident.

A week later she alleged Boulter raped her again one night in her home.

"[She] described being in shock and panicking.

"She talked about being 15yrs, underage and not wanting to get into trouble."

She said Boulter was "laughing, smiling, and smirking".

"Before leaving, Boulter threatened to kill [the woman's] father if she said anything."

The third incident, an allegation of assault with a weapon, occurred when the pair ran away together days later.

The woman told police they spent about two days hitchhiking together, using her money to fund the trip.

While on the main street in Balclutha the pair had an argument and Boulter allegedly presented a knife and pressed it against the woman's neck. She said she ran off and sought help at the Balclutha Pub where two women helped her.

The woman told police that she "went off the rails" in the years that followed.

Boulter was interviewed by Detective Jason Bishop from the Waikato Child Protection Team at Otago Prison on 24 June, 2021.

Boulter was formally cautioned and provided with legal advice. After speaking to a duty lawyer he declined to provide a statement.

"In response to the allegations Boulter denied any wrongdoing. He informed Detective Jason Bishop that [the woman] was his girlfriend during the period in question.

"Boulter stated that the sex that occurred between the two was not rape and commented on it being his first sexual encounter."

The police report said that "notably" the woman had earlier described Boulter as being the first person she had sex with.

"She also commented on him being a popular classmate, appreciating him showing interest in her on occasion and talking about school camp where there was some positive interaction involving leg touching."

The author of the report said it was their "personal belief that the requisite evidence is not present" to meet the Solicitor-General's prosecution guidelines.

"In my opinion the required minimum standard for a prosecution is not attained and to do so would risk a possible miscarriage of justice."

In relation to public interest, the author said there was "no doubt" the matter was serious enough that public interest could require a prosecution, but identified several matters to consider. This included where a prosecution was likely to have a "detrimental impact" on the physical or mental health of the victim, and where the defendant was a youth at the time of the alleged offending.

It was recommended the matter should be filed.

The woman told RNZ going to police in 2021 was "one of the hardest things I've ever done".

She was "devastated", when police told her they would not be laying charges.

"I felt misheard and abandoned. I lost faith in the justice system's ability to protect victims and prevent repeated harm."

The woman was referred to mental health services in June 2003 by the principal of Apirima College and a counsellor.

The counsellor's referral, seen by RNZ, said the woman had been going through a "difficult experience as a result of a break-up with a year 10 boy in her class with whom she had a sexual relationship".

"It is my impression that [the woman] has been subject to severe emotional and physical pressure from this youth in order to obtain sexual favours since the break-up."

The woman was "fearful" of the possibility of Boulter returning to school following an extended suspension.

The counsellor noted that the woman's father told them that he had spoken to the police.

Notes seen by RNZ said she was referred following concerns about her mood, self-esteem and PTSD after "an abusive relationship" with Boulter.

"Nathan has consistently been emotionally + physically abusive including slapping her around, pushing her to the ground at school, frequently stating he would kill himself if she did not comply to his demands.

"[The woman] has also been under pressure to give sex when she would otherwise wouldn't have."

The notes from the intake nurse also said Boulter had threatened to kill her, at which point her father contacted police and a protection order was put in place.

The woman said police were notified of her allegations in 2003. However, a privacy act request she made did not find any record of any complaints at the time.

The woman told RNZ Boulter was "controlling, possessive, and violent".

"I was terrified of him, but I felt trapped because no one seemed to take it seriously."

She said she heard about Boulter being charged with murder from friends in Riverton.

"My heart sank," she recalled.

"My reaction was one of grief, disbelief, and anger. It brought everything back. I was heartbroken for the victim and her family in Christchurch and it confirmed my fears that the warning signs were there all along, but no one intervened when they could have."

She wants to see Boulter "locked up indefinitely".

"I want people to understand that these patterns of harm don't happen in isolation. When victims are dismissed or disbelieved, it allows offenders to escalate.

"I hope sharing this encourages better accountability, for schools, police, and communities to act decisively when young people report harm. Because if someone had acted 20 years ago, this story could have had a very different ending."

Case 'did not reach the threshold'

Waikato district manager of criminal investigations Detective Inspector Daryl Smith told RNZ police immediately began an investigation in 2021 when the woman came forward.

The investigation included interviewing both parties involved.

"Upon reviewing all the available evidence, the matter did not reach the threshold to prosecute under the Solicitor-General Prosecution Guidelines."

At this stage, police had no intention to review the matter, Smith said.

"However if any further information comes to light then police will of course assess this and action any appropriate follow up as required."

Where to get help:

Sexual violence

• NZ Police.
• Victim Support 0800 842 846.
• Rape Crisis: 0800 88 33 00.
• Rape Prevention Education.
• Empowerment Trust.
• HELP (Auckland): 09 623 1700, (Wellington): 04 801 6655.
• Safe to talk: 0800 044 334.
• Tautoko Tāne Male Survivors Aotearoa.
• Survivors Network of those Abused by Priests (SNAP) 022 344 0496.

Family violence

• Women's Refuge: 0800 733 843.
• It's Not OK 0800 456 450.
• Shine: 0508 744 633.
• Victim Support: 0800 842 846.
• HELP Call 24/7 (Auckland): 09 623 1700, (Wellington): 04 801 6655.
• The National Network of Family Violence Services NZ has information on specialist family violence agencies.

If it is an emergency and you feel like you or someone else is at risk, call 111.

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