A Dunedin teenager who bludgeoned his mother to death with a 10 kilogram dumbbell has been sentenced to life in prison with a minimum of 10 years behind bars.
Jordan Taylor attacked his mother, Anita Taylor, on 14 January shortly after celebrating his 18th birthday, drinking with her and a friend the evening before.
He then placed a towel on the stove top and turned it on before packing a bag and walking four kilometres to a stranger's house to call the police.
He pleaded guilty to her murder earlier this year and was sentenced in Dunedin High Court in October, with details suppressed until Monday.
Crown prosecutor Richard Smith said this murder involved a high level of brutality and callousness.
The Crown accepted that the teenage was in many respects the victim of psychological and emotional neglect at the hands of the victim, but that did not excuse what he had done, Smith said.
He detailed an expert's report, which said the teenage described being in a good mood and enjoying the night despite feeling some anxiety.
But not long after his friend left, the mood shifted.
"He explained that his mother got angry, accused his friend of stealing a bluetooth speaker, that appears to be an entire misunderstanding of course, and the victim rather berated (the teenager) and said a number of unpleasant things."
After she went to bed, he picked up the 10 kilogram dumbbell, turned out the hallway lights and walked into her bedroom, attacking her as she was lying in bed, striking her head several times.
Smith said she was essentially defenceless.
The report suggested that the teenager recognised that he had inflicted significant injuries on his mother and then decided to finish her off, he said.
"It was rather more couched as putting the victim out of her misery, believing that her injuries wouldn't be survivable."
Defence counsel Sarah Saunderson-Warner said he grew up wholly dependent on his mother, isolated from his father's side since he was two and periodically from his mother's family.
It was a volatile relationship where the victim went from abusing him to protecting him, she said.
His past did not justify his actions, but it did provide the context, she said.
"Throughout his childhood, he was entirely dependent on his mother for nurturing, love and support, and sadly that was not consistently provided."
She said her client had taken full responsibility for his actions.
Justice Melanie Harland acknowledged he had experienced maltreatment for most of his life, but said that did not excuse what he did.
She accepted he was extremely remorseful, quoting what he said to one of the report writers, including his plans to address his behaviour, "personal demons", and drinking.
He told the report writer: "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.
"I feel so in pain from what I have done that it is so hard to even process my feelings. I hope maybe she is in a better place. I want to make sure I become a better person in prison."
In the sentencing, Justice Harland said the decision was extraordinarily difficult.
"Even though you are young and now appear to have significant family support, whether you can overcome the trauma of your past remains to be seen.
"I hope you can but, without further certainty, in my view, there remains the need to protect the community, in this case, from others who you may become close to."
An impact statement from Anita Taylor's father was read to the court, saying it seemed like they blinked and their future suddenly changed forever.
"To lose something that is a part of me is one of the most dramatic events that I have ever had to face. The loss of my little girl is very severe."
He spoke about his daughter's dreams to own and renovate a home on a plot of land and that she would never get to experience that.
"Despite our best intentions not to dwell on what has happened it comes back in so many ways and it can be daunting to repeatedly go through the chain of events that culminated in this tragedy.
"I know it will never go away, but I'm hoping that it will get easier."