A psychiatrist has told the High Court in Auckland that a boy accused of killing a dairy owner knew right from wrong, and understood it was wrong to hurt people.
Arun Kumar. Photo: NZ POLICE
The boy, who is now 13, is charged with the manslaughter of Arun Kumar in Henderson last June.
Another boy, who is 14, is charged with murder. Neither can be named.
Presenting their case to the jury, the younger boy's lawyers said he had no plan to hurt anyone, and that there was no plan to stab or kill.
Psychiatrist Andrew Immelman, who was called by the boy's lawyers, said drugs and alcohol undoubtedly affected the boy's development before he was born.
Dr Immelman said he could not be described as a normal boy for his age, and that he had been diagnosed with a severe conduct disorder.
"There is no way I could describe his childhood as normal, nor could I describe his cognitive ability as normal."
He said the boy was known for tagging, damaging school property, aggression toward people, getting into fights, and he had a history of lying, stealing and disregarding authority.
Dr Immelman said there was compelling evidence the boy's physical and emotional needs were not adequately met.
"He was exposed from a very young age, exposed to neglect and severe domestic violence... I believe his environment was unpredictable," he said.
"He saw violence and disrespectful behaviour, especially towards women, and like any child he would have modelled his behaviour."
The boy's upbringing was "likely to have caused structural changes in his brain", and his own drug use would also have affected his development, Dr Immelman said.
But under cross examination by the Crown, Dr Immelman accepted the boy knew it was wrong to steal, hurt, or stab people.
Accused's mother gives evidence
Earlier in the day, the boy's mother gave tearful evidence for his defence, detailing how she drank and used drugs while pregnant with him.
She said she was in prison for methamphetamine possession at the time of the fatal stabbing.
The woman, who cannot be named, said she blamed herself for staying in a violent relationship that terrified her children and made them hide under the bed.
"I blame myself because I was living the lifestyle, I just kept going, I blame myself for that," she said.
"As soon as we started arguing they would hide under the bed, they'd automatically run as soon as they could see what was going to happen.
"It got to the stage where they knew and they hid before it all happened... It happened enough, too much... more than they should have seen," the mother said.
She told the jury she used even more drugs and neglected her children.
Drugs were used to cope - lawyer
One of the boy's lawyers, Phil Hamlin, said the teenager used drugs to cope.
"His brain development after birth was impaired by childhood abuse and, principally, neglect... he began using drugs to cope."
Mr Hamlin told the jury the boy could not foresee the consequences of the older boy using a knife.
Flowers placed Arun Kumar's dairy. Photo: RNZ
The boy's tearful grandmother also gave evidence for his defence.
"It got worse from the time he was born - I felt she wanted to pull away but she couldn't, and then it got very violent.
"I could see she wanted to pull out but it was too late," she said of her daughter.
She said her daughter was not coping with her children, would not get up in the mornings and that "the whole house had gone backwards".
She said the boy started declining when his mother was jailed in 2013.
"He got quite down, he was just sad, depressed.
"There was nothing I could do - normally Nana could fix everything but I couldn't fix that - he said to me 'I don't want to live anymore'," she said.
The jury has retired for the day and will return at 2pm on Thursday to hear the Crown's closing address.
The defence closings will be heard on Friday, and the judge has indicated he will sum up the case on Monday - after which the jury will retire to consider its verdicts.
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