The one-punch manslaughter trial of Carlos Pula is a who-done-it.
The Crown prosecutor, Fiona Culiney, today told the High Court in Auckland Mr Pula was in fight-mode when he uppercut punched Reginald Sharma, splitting an artery in his neck and causing his death.
But Mr Pula's lawyer said it was a dark night, witnesses couldn't get a good look at what happened and his client has a pre-existing wrist injury that means he can't form a fist.
Ms Culiney said Mr Pula had been solidly drinking for hours at a 21st party in Three Kings in August last year.
It was in the early hours of the morning when Mr Pula got into a fight with another one of the guests.
"He'd been in an altercation and he'd been pushed over, and hit, and yelled at and he was in fight-mode. He was angry and he was looking for someone to take it out on."
Ms Culiney said Mr Pula's attack on Mr Sharma was completely unprovoked.
"He was minding his own business, he didn't engage in any fighting, he certainly didn't engage in a fight with this man. He didn't provoke him in anyway. He was just having a good night, having a good time," she said.
"And [Mr Pula] uppercut him, or hit him in the side of the face, just on his left side of his jaw here. And he swung his head around and this split an artery in the back of his head."
Mr Sharma's split artery caused bleeding on his brain and he died as a result.
Ms Culiney said the main issue in the case will be identity.
"Was it this man who did this, as the Crown says? Was it this man who hit Reggie Sharma that night?"
She said she would call nearly all the people who attended the party and the witnesses will provide various pieces of the jigsaw.
"Two people were able to pick the defendant out of a photo montage. Two people saw an uppercut, punch, or a hook to his face, his mouth, his jaw."
Mr Pula told police he didn't go up to the house, but then changed his story to say he was only up the driveway a short time to pick up his partner.
Ms Culiney said Mr Pula also told the police that he had an injury to his wrist in 2012, which meant he could not form a fist. But she said CCTV footage captured of Mr Pula on the night shows him using his hands.
"You can see for yourself he's holding drinks ... And he's making fists with his hand, and he's clasping his hand with others and greeting them and shaking their hands and so on."
Mr Pula's lawyer, Mark Edgar, agreed with Ms Culiney that the case will come down to identity.
He said many of the witnesses at the party were effected by alcohol and it happened in the early hours of the morning.
"You've got this lovely book of photographs that the police have very helpfully provided. The only trouble is these photographs were taken in the daytime and the defence will say to you, this scene looks remarkably different at night."
Mr Edgar said there will also be a battle of the experts as both the Crown and the defence will call witnesses to give evidence about Mr Pula's ability to clench his fist.
"The defence says to you, Carlos Pula cannot do that, he cannot make a fist, despite what the Crown might say. So you will be aware of that issue when that comes about."
He said the jury would need to consider whether Mr Pula even had the capacity to throw the punch.
The trial before Justice Hinton and a jury is due to hear evidence from 30 witnesses has been set down for two weeks.