Key Points:

A man today found guilty of the manslaughter of a tagger, but not guilty of the 15-year-old's murder, is likely to appeal.

Bruce Emery had denied murdering Pihema Cameron in Manurewa last January, arguing he had been defending himself.

The verdict was delivered by a jury at the High Court in Auckland this afternoon.

His lawyer Chris Comesky said the defence of provocation, which reduces murder to manslaughter, was not used by the defence, but was made available to the jury by the judge.

"I was concerned at the time. I remain concerned," he said.

"And I'll be frank to the extent that if it looks like a reasonable possibility that it shouldn't have been put, then obviously that matter will be looked at."

Mr Comesky said he will seek to keep Emery out of prison when he is sentenced on February 13.

"Taking a husband, a father, a businessman, someone who has never been in trouble in his life - one would struggle to see... the rationale in simply dumping him into a prison."

He expressed relief that his client had been cleared of murder, saying Emery was exhausted after the trial.

Justice Hugh Williams told the court some people would be pleased with the verdict and some would not.

"But please acknowledge that the jury has worked long and hard to reach the verdict so please restrain yourself as much as you can," he said.

He told the jury: "Thank you for the work you have done in reaching the verdict, and your work throughout the week".

It is likely Emery will appeal his conviction for manslaughter.

Pihema's mother hugged a young girl beside her in court as the verdict was announced before putting her head down and beginning to cry, Newstalk ZB reported.

Emery himself took a deep breath as the jury entered the courtroom but showed no emotion as the verdict was read out.

Some members of his family were also present and stayed behind in the courtroom.

There was a strong police presence in the courtroom and corridors.

Pihema and a friend, 16, had been tagging properties and Emery thought they had tagged his garage door. He chased them for more than 300m then confronted the pair.

Pihema died within minutes of being stabbed in the chest with a kitchen knife Emery carried.

Public opinion

Before jurors retired to consider its verdict about 11.00am yesterday, Justice Williams warned them not to be swayed by public opinion.

"You have to be entirely un-influenced by prejudice or sympathy for anyone in the case," he said.

Justice Williams told jurors that to convict Emery of murder the Crown had to have proven Emery meant to cause Pihema "bodily injury" and that he was likely to have caused his death and injury.

They also needed to have proven that Emery was reckless - that death could have happened as a consequence of his actions.

For the jury to believe Emery - who maintains he was defending himself - they had to be satisfied he felt there was an "imminent force to be resisted".

Crown case

The Crown closed its case against Emery on Wednesday and, with the defence not calling any witnesses, both sides summed up their cases to the jury.

Prosecutor Aaron Perkins said Emery was not defending himself but using his anger to punish them for tagging his garage door.

"On a daily basis people do worse things than what Pihema Cameron did to this man. People are expected to show restraint, not take the law into their own hands."

Mr Perkins said Emery was "an angry man" who had a history of vandals tagging his property. "And he finally catches one."

"The combination of an angry man with a potentially lethal weapon. The outcome... is what we see here," he told the jury.

He asked them to consider the evidence of Pihema's friend, who has name suppression, and what Emery told police.

The friend said Emery had thrust his knife at Pihema while Emery claims the teen "stepped into" it.

Mr Perkins said Emery couldn't use self-defence as defence because that could only be legally used if that was the main motivation.

"He used the knife not in self-defence, but to vent his anger."

Defence case

Emery's lawyer, Chris Comeskey, told the jury that what happened was not murder but self-defence.

The events that night happened quickly and Emery didn't have time to think, grabbing a knife when he should have grabbed a "non-lethal" weapon like a rubber hose.

"The accused could have gone home - but that doesn't make him a violent killer. He took a risk. If he's as angry as the Crown is saying, why wasn't it a frenzied attack?"

The knife that killed Pihema had a 14cm blade but a pathologist found it penetrated him only 5cm.

"It's more probable the deceased hasn't seen the knife and he's walked into it," Mr Comeskey said. "The pathologist said the knife went in 5cm, so it can't have been caused by a thrust."

He said if jurors had reasonable doubt whether Emery put the knife into the teen they had to acquit him.