Jordan Taylor, 18, will now have at least a decade behind bars to come to terms with murdering Anita Jane Taylor.
Justice Melanie Harland told the High Court at Dunedin last month that, given the background, it was an "extraordinarily difficult" decision as to whether or not to impose life imprisonment for the murder.
A life term in such circumstances can only be avoided if it would be manifestly unjust, but the judge said there was a need to protect the community.
"I am not talking [about] the community at large, I am talking about people who you might enter close domestic relationships with in the future," she said.
The Court of Appeal yesterday confirmed Taylor had since appealed the sentence but no date had yet been set for a hearing.
Justice Harland’s sentencing from October 18 was embargoed so the scope of suppression orders could be finalised, and a final decision was released yesterday.
Taylor had been celebrating his 18th birthday at his Helensburgh home, drinking with his mother and his friend on January 13.
The defendant later said he had enjoyed the night but shortly after he and the victim had been left alone, the tone changed.
He described an intoxicated Ms Taylor berating him for several minutes and telling him she wanted to die.
It was the worst thing she had ever said, Taylor told a psychologist.
"[He was] absolutely isolated and alone, without the skills to cope ... Because of all that he snapped," counsel Sarah Saunderson-Warner said.
But Crown prosecutor Richard Smith highlighted some of the seemingly more deliberate aspects of the attack.
Taylor admitted turning out the hallway lights before going into his mother’s bedroom to bludgeon her.
He told one clinician he had never harboured violent thoughts towards her before but after the first blow he decided to "finish her off" with two more, while he told another it was actually four further blows, and it was to put her out of her misery.
The teenager then put a tea towel on the stove and turned it on, packed a bag and walked north.
However, 4km from his home he phoned police and admitted what he had done. Once they found the victim dead, they returned to where Taylor had made the call.
He was waiting in his bloodstained clothes, the court heard.
Justice Harland said the background to the case was pertinent.
While she spoke at length about the "complex" relationship between mother and son — much of which was suppressed — she reiterated nothing excused Taylor’s brutal actions.
"The relationship between you and your mother was characterised by her being verbally, emotionally and psychologically abusive towards you, while at the same time, being protective of you and loving towards you," the judge said.
She described how Ms Taylor, who reportedly had "a fiery temper", had isolated herself and her son from the wider family and as a result had created an unhealthy co-dependence.
Justice Harland accepted the defendant felt extreme remorse for his actions.
"I think about her every day. I never meant to express any hatred towards her. She was the only person in the world that I loved. I feel awful for what I did. I feel deep remorse for my family, and I hope that they can forgive me," Taylor said when interviewed.
"I hope maybe she is in a better place. I want to make sure to become a better person in prison ... I think alcohol had a big part to play in [it] ... I promise to not ever drink again."
There was a large contingent of family support in court for the teenager, and Ms Saunderson-Warner said they were now committed to being there for him.
Justice Harland said that assistance would be vital, as would extensive therapy.
In imposing the life term with a non-parole period of 10 years, she urged Jordan Taylor to remain positive.
"This does not mean there is no hope for a better future for you," she said.
Ms Taylor’s father David said the loss he had endured was "very severe".
"I know it’ll never go away but I’m hoping it will get easier," he said.
He told the court his daughter had always wanted a little plot of land to develop.
"Maybe she has one in heaven," he said.
Making a teen murderer
— Only child; parents separated when Jordan Taylor was 2; mother did not permit a relationship with his father.
— "Internally focused" relationship between mother and son; interacted with few family or friends.
— Pair moved house frequently; Jordan Taylor attended several schools: did well academically, floundered socially.
— Mother Anita Taylor struggled financially and psychologically; may have been depressed.
— Neither mother nor son had hobbies, played sports or attended community groups; neither drove.
— Jordan Taylor’s only friend said he would spend days in his bedroom alone.
— He likely suffered a depressive illness leading up to the murder; had PTSD from earlier incident.
rob.kidd@odt.co.nz , Court reporter
