The man who stabbed a Christchurch woman to death at her own home after she ended their relationship is not the first violent offender in his family to be jailed for murdering an ex-partner, the Herald can reveal. 

Nathan Boulter, 36, killed Chantal McDonald in front of her children at her home in Parklands in July 2025. 

The pair had been in a brief relationship, and McDonald dumped Boulter when he was recalled to prison, making it clear she wanted nothing more to do with him. 

Chantal McDonald. Photo / Supplied 

Boulter became obsessed with the 37-year-old, and after a “campaign of harassment” including hundreds of phone calls and threatening text messages, he bought a large hunting knife and stabbed her 55 times as she returned home from the supermarket with her kids. 

Boulter was subject to prison release conditions at the time. 

Corrections has carried out a review of his monitoring, and a report has been provided to the Coroner before an inquest into McDonald’s death and whether it could have been prevented. 

Now, the Herald can reveal that Boulter is a nephew of Warren Leslie Boulter, who was jailed for life after he beat and stabbed Sharyn Wilkinson-Foley to death in 2012 when she tried to end an abusive relationship with him. 

Sources said Nathan Boulter’s mother is one of Warren Boulter’s five siblings. 

Nathan Boulter appeared via AVL for sentencing at the Christchurch High Court. Photo / Chris Skelton / Pool 

One of Warren Boulter’s children -Nathan Boulter’s cousin - indicated the family were very reluctant to speak about the killers. 

“The actions one chooses to make are their own,” she said. 

“What Nathan done and what my dad done is of their own choice - with consequences - that us family suffer for.” 

Warren Boulter was sentenced to life in prison with a minimum non-parole period of 13 years in 2013. 

“No doubt the Parole Board, many years into the future, will wish to think very carefully about whether you any longer pose a serious risk to women before they consider releasing you from prison,” said Justice Ronald Young at his sentencing in the High Court at Nelson in October 2013. 

“There can be no doubt, Mr Boulter, that you are a great danger to women that you have a relationship with. You seem to think that they should bend to your will and desire no matter what.” 

Wilkinson-Foley was found dead in her Richmond home by her parents in May 2012. 

“[She] made it clear that she had decided she no longer wished to have a relationship with you. You decided she could not be permitted to make that decision,” said Justice Young. 

“You refused to accept it. You were aggressive and threatening towards her and I am sure that shortly after you arrived at that house you began beating her.” 

On the day of the murder, Wilkinson-Foley had arranged for Warren Boulter to pick up some clothing he had left behind. 

He began punching her in the face and knocked her to the ground. 

He then went to the kitchen and selected a knife. 

“You stabbed her repeatedly and violently in the neck. You caused her severe injuries. She bled to death,” said the judge. 

“As she must have lain dying, you showered, changed your clothes and … left the house. You would have known that she would have [been] slowly bleeding to death. 

“You showed no interest in her and then you tried to disguise the killing and your involvement. But eventually you were arrested and stood trial. You denied that you were the killer but the evidence overwhelmingly said that you were.” 

Nathan Boulter. Photo / Richard Robinson 

Justice Young accepted that Warren Boulter may not have been planning to kill Wilkson-Foley before he got to her home. 

“But after you assaulted her, it is clear to me that you were determined to kill her,” he said in court. 

“The way in which the knife was used, stabbing her in the neck in a violent way, illustrated the ferocity of your attack. 

“This was a callous, brutal killing of a woman you shortly before had a relationship with and you claimed to have loved.” 

The court heard that Warren Boulter had “a history of violent reactions when a relationship ends”. 

He refused to speak to pre-sentence report writers and “made no sign of any remorse or any willingness to make amends”. 

“This again emphasised the cold-blooded killing of this woman,” Justice Young said. 

“The propensity evidence called at trial illustrated that on a previous occasion when a woman had decided she no longer wished to have a relationship with you that you acted violently towards her and threatened to kill her. And you were imprisoned then. 

“I repeat. You are a clear and obvious danger to women.” 

Wilkinson-Foley’s parents and sisters read victim impact statements in court at the time. 

“Our lives have been shattered, our hearts are empty, part of us have gone with her. There will always be a huge hole in our lives that nothing or no one can fill,” her parents said. 

One of her sisters said: “You have destroyed our family and changed our lives forever and yet you show no emotion and, even more distressing, no remorse for the evil crime that you have committed.” 

Warren Boulter was jailed for life in 2013 for murdering his ex. Photo / File 

Justice Young said the statement “stresses the deep loss and permanent effect” that her death had. 

“This is a family that has been shaken to its core by your murder,” he said. 

“I acknowledge their dignity and their loss.” 

Nathan Boulter’s offending, criminal history and sentencing circumstances were eerily similar. 

He also used a weapon to stab his ex to death at her own home before fleeing. 

He too has a documented history of offending against women, including violence, kidnapping, threats, stalking and harassment. 

His offending has escalated towards women ending relationships with him. 

In 2011, he kidnapped Nortessa Montgomerie on Great Barrier Island, assaulting her repeatedly for almost 40 hours. 

Montgomerie had left Boulter after earlier assaults at the home they shared in Southland and he had been banned from having any contact with her. 

He ignored court orders and travelled to Auckland, where he subjected her to a terrifying ordeal. 

Nathan Boulter was jailed for eight and a half years in 2012. Photo / File 

After he murdered McDonald, Boulter also refused to speak to pre-sentence report writers. 

He did not convey any remorse. 

On Wednesday, Justice Owen Paulsen sentenced Boulter to life in prison with a minimum non-parole period of 17 years. 

He said Boulter had 50 previous convictions and had been sentenced to prison 42 times from 2006 to 2025. 

The murder was a significant escalation of his previous offending. 

“There is a pattern of unhealthy fixations with ex-partners, with extreme electronic harassment escalating to threats of violence - and I note that legal sanctions including imprisonment and the imposition of specific releases have not prevented further serious offending,” Justice Paulsen said. 

“Your risk of reoffending and the risk you pose to the community are considered to be very high.” 

Crown prosecutor Pip Currie described the murder as “overkill”. 

“It was an extremely determined assault,” she said. 

“It was designed to be deadly and there was an unnecessary level of violence – and consider perhaps the length of time that would be required to carry out that many blows.” 

She noted that McDonald was “ “locking herself in” to her property when Boulter struck. 

“Ironically … to protect or prevent this offender from gaining access,” she said. 

Justice Owen Paulsen. Photo / Chris Skelton / Pool 

McDonald’s daughter spoke for the first time at sentencing about the murder. 

“I witnessed the attack on my mum and what I saw and heard that day has had a severe and ongoing impact on me,” she said. 

“The images, the injuries, and the screams come back to me without warning … the way my mum was taken from us was violent and disgusting, and the pain that I’ll continue to carry with me is something that nobody will ever understand. 

“My mum was stabbed not only once, not twice, but 55 times all over her body, head, and her face – and I’m the one that has to live with those horrific visions.” 

McDonald’s aunt said Boulter was “cold and emotionless” and she “felt so much anger”. 

“I can only hope you will be haunted by your actions for the rest of your life,” she said. 

“May you suffer the way you made our girl suffer.” 

FAMILY VIOLENCE 

How to get help: If you're in danger now:
• Phone the police on 111 or ask neighbours or friends to ring for you.
• Run outside and head for where there are other people. Scream for help so your neighbours can hear you.
• Take the children with you. Don't stop to get anything else.
• If you are being abused, remember it's not your fault. Violence is never okay.

Where to go for help or more information:
• Women's Refuge: Crisis line - 0800 REFUGE or 0800 733 843 (available 24/7)
• Shine: Helpline - 0508 744 633 (available 24/7)
• It's Not Ok: Family violence information line - 0800 456 450
• Shakti: Specialist services for African, Asian and Middle Eastern women and children.
• Crisis line - 0800 742 584 (available 24/7)
• Ministry of Justice: For information on family violence
• Te Kupenga Whakaoti Mahi Patunga: National Network of Family Violence Services
• White Ribbon: Aiming to eliminate men's violence towards women.
 

Anna Leask is a senior journalist who covers national crime and justice. She joined the Herald in 2008 and has worked as a journalist for 20 years with a particular focus on family and gender-based violence, child abuse, sexual violence, homicides, mental health and youth crime. She writes, hosts and produces the award-winning podcast A Moment In Crime, released monthly on nzherald.co.nz