Justice Rachel Dunningham remanded him in custody to December 12 for sentencing.
The name of the victim was suppressed.
And it can be revealed that Boulter, 36, has a horrifying history of violence against women, including a high-profile kidnapping on Great Barrier Island in 2011.
Nathan Boulter. Photo / Richard Robinson
In January 2011, Boulter subjected his ex-partner Nortessa Montgomerie, then 21, to physical attacks and terrifying threats over 38 hours after he bashed her unconscious and dragged her from her father’s home on Great Barrier Island.
Montgomerie’s ordeal only ended when she managed to convince Boulter that she wanted to leave the island with him. Police said in doing that, she saved her own life.
Boulter pleaded guilty to nine charges, including kidnapping and wounding with intent and was sentenced to eight years in prison.
The court heard that, in 2010, Boulter and Montgomerie were in a relationship and living together in Southland.
He was charged with assaulting her after two separate incidents in September and October. Boulter was released on bail and was ordered not to have any contact with his victim – and to remain at his approved address in Southland.
To avoid any further contact with her abuser, Montgomerie moved back to Auckland, to her father’s home on Great Barrier Island.
On Boxing Day, Boulter breached his bail conditions and travelled to Auckland to try and find Montgomerie. On New Year’s Eve he sent her a message saying he was going to take his own life. Four days later he sent a second message threatening to kill her.
Police leading Nathan Boulter in handcuffs from the police launch at Mechanics Bay after his arrest on Great Barrier Island in 2011. Photo / Michael Craig
On January 17, Boulter booked a one-way ferry ticket to Great Barrier Island under a false name. He arrived at 11.30am and made his way to Montgomerie’s father’s home.
He waited until it was dark and then entered the house and hid under Montgomerie’s bed.
She was at the house with a male friend, her 7-year-old brother and his friend.
When Montgomerie and the other man went to bed, Boulter struck. He hit the man on the back of the head with a hard object, continuing the assault when the man fell to the floor.
Montgomerie begged Boulter to stop and in response, he hit her in the head. He hit the man repeatedly until he was unconscious and then chased after Montgomerie, who had run for help.
He caught the 21-year-old and dangled her over a balcony by her leg and hair. He dragged her back up and rendered her unconscious by punching her in the back with your fist and kneeing her in the head.
Armed with “a weapon resembling a thistle grubber” Boulter took Montgomerie from the house.
Dragged, abused, threatened
For 15 hours and during a fierce storm, he held Montgomerie – wearing only a singlet and pyjama bottoms – in isolated bush.
“At times you dragged her across undulating terrain in the bush … you abused her physically over this period. That abuse included physical attacks and strangulation that led to serious injuries. Your intent in doing so was to cause really serious harm to her,” said Justice Paul Heath Boulter’s sentencing.
“After all of that, Ms Montgomerie was able to persuade you to dispose of a weapon by throwing it into a stream and to walk together towards the wharf to escape. Later in the day, searchers located the two of you. Ms Montgomerie’s ordeal finally came to an end.”
Montgomerie suffered haemorrhaging to both eyes and a brain bleed from strangulation as well as bruising and swelling to her head and body and abrasions to her feet.
Her friend suffered a fractured skull at the front of the head and bruising and swelling to the rest of his body.
“One only has to read the victim impact statements to realise the horrific situation in which they found themselves and the emotional and physical harm that has been done to them. Without seeking to minimise the harm caused … the physical and emotional injuries to Ms Montgomerie were much more profound.
“I hope that what you heard from her has some impact on you in understanding exactly what has resulted from your actions over those few days.”
Justice Heath said Boulter’s offending “involved a pre-conceived plan to travel almost the full length of this country to confront” his victim.
“At the time, you were on bail in respect of domestic violence charges that had been laid in Invercargill. It is fair to say that nobody could have foreseen the trouble to which you went to meet up with Ms Montgomerie, in contravention of your bail conditions,” he said.
“You then embarked on what can only be described as a course of conduct over a protracted period of time during which extreme physical violence was inflicted on Ms Montgomerie.”
Justice Heath was provided with a psychiatric report outlining Boulter’s “complex” personal circumstances and diagnosed with “psychotic disorder”.
“Your symptoms do not meet the criteria for any specific type of disorder. Nevertheless [it is] clear that you have an underlying psychotic illness which has responded positively to a trial of psychotropic medication … if your psychotic symptoms were to persist, it could lead ultimately to a diagnosis of schizophrenia, a major psychotic disorder.
“As a result of taking prescribed medication while in custody, your mental health state is now stable and you do not currently experience aggressive ideation or impulses.”
Justice Heath said the link between Boulter’s “abnormal state of mind” and the offending did exist – but remained “tenuous”.
Boulter wrote letters to his victims but Justice Heath said he was “unsure about the
degree of insight” the offender actually had into the harm he caused.
“I have concerns about your inability to empathise adequately with your victims,” he said
“I am prepared to accept some link between the historical nature of your diagnosed disorder and your offending. There is also evidence of borderline personality disorder with anti-social traits … I am prepared to accept that the underlying mental condition probably removed natural inhibitions that usually prevent human beings from acting in this brutal and callous way.”
He held her there for 38 hours and subjected her to numerous assaults.
In July 2020, he was locked up after visiting a woman’s home, taking photos and, over the course of a single day, calling her 300 times and leaving more than 100 voicemail messages.
Another woman attacked
In 2020, Boulter was back before the courts after offending against a second woman.
The woman was a friend of Boulter’s sister in Southland who he started messaging and soon became obsessed with.
He became aggressive and threatening, he stalked her, and he threatened to kill her.
On one occasion, he went ot her home and later threatened his sister that he would return with a sawn-off
On another occasion, he assaulted the woman and “advised her to kill herself”.
Boulter was sentenced to three years and two months on seven charges of threatening to kill, contravening a protection order, assault with intent to injure and causing harm by digital communication.
He was refused parole a number of times – including when the board learned he had not undertaken any rehabilitation programmes in relation to his offending.
But by April 2023, Boulter managed to convince the board that he could be released safety back into the community.
Parole Board panel convenor Mary More noted Boulter’s “serious” conviction history.
Alongside the Montgomerie kidnapping and stalking, there were a raft of convictions for “other violence, kidnapping and burglary”.
Despite his dark past, More said Boulter’s parole assessment report stated he had “positive behaviour”.
“And he has said that he is determined not to do this again,” she said.
The board heard Boulter planned to live with his mother and had the support of his family, that he had “insight into his mental health” and “knows when he is unwell and the impact on his behaviour”.
More said Boulter “spoke very well” about “his warning signs”, including “substance abuse and going into an intimate relationship”.
She noted that Boulter had just five weeks left of his sentence, so if the board wanted to impose any conditions at all it had to grant his release.
If he served the full sentence, he would leave prison a free man with no conditions or monitoring.
“The board considers that any undue risk Mr Boulter poses can be met by way of special conditions,” she said.
Those conditions included two months of electronically monitored residential restrictions and taking his medication.
For six months, Boulter was ordered to live at an approved address, not to consume alcohol or illicit drugs, not to contact any victims of his offending and to disclose all details about any intimate relationship which commences, resumes, or terminates to his probation officer.
He was not subject to any parole conditions when he murdered the woman in Parklands.
More to come
Al Williams is an Open Justice reporter for the New Zealand Herald, based in Christchurch. He has worked in daily and community titles in New Zealand and overseas for the last 16 years. Most recently he was editor of the Hauraki-Coromandel Post, based in Whangamatā. He was previously deputy editor of the Cook Islands News.