A teenager is “lucky he’s not facing a manslaughter charge” after knocking out a police officer who was trying to break up a fight outside a nightclub.

Matua Ratana today asked Judge Arthur Tompkins to discharge him without conviction for the “serious and unprovoked assault”, saying he was instinctively trying to protect a female friend at the time.

Ratana, 19, appeared in the Wellington District Court this afternoon, having earlier pleaded guilty to injuring with intent to cause grievous bodily harm, and resisting arrest.

About 4am on Sunday November 6, Ratana was drinking on Courtenay Place in Wellington’s central city with a group of close female friends his lawyer said he considered sisters.

Police officers patrolling the area noticed two women fighting, and began moving through the crowd to break up the fight, Judge Tompkins said. The fight is not believed to be connected to Ratana’s female friends, but in the process, a police officer trying to make his way to the fight pushed one of them.

The incident happened on Wellington's Courtenay Place. File photo / Mark Mitchell

Ratana’s lawyer, Ainslie Teki, said he “saw one of his friends being pushed around by a police officer and he reacted in a way that he thought was protecting her and he did swing his fist at the police officer”.

Judge Tompkins said Ratana hit the officer with a closed fist on the side of his head, knocking him out and causing him to immediately start bleeding from the mouth. The officer was hospitalised and suffered a concussion.

The officer was “painfully aware” if the punch had been just a little bit higher “the result could have been drastically different”, the judge said.

 “He’s lucky he’s not facing a manslaughter charge,” he told Teki.

Ratana then fled the scene on foot and struggled against arresting officers, who had to pepper spray him. One of the officers suffered a rotator cuff injury to their shoulder during the arrest.

Teki said Ratana’s actions in punching the officer were “in the heat of the moment” and influenced by a “mistrust” of police. She said he had a bad experience with police once where he was restrained on the ground while walking down the street with a friend.

It is not clear what the circumstances of that incident were, she said.

The police officers were just trying to do their jobs when the attack happened, Judge Tompkins said.

Ratana was 18 at the time of the offending and had no previous convictions. He also wanted to “explore” taking part in restorative justice, and had made a $100 donation to the Child Cancer Society.

She said a conviction would be out of proportion to the offending and would impact Ratana’s ability to find work and help care for his seven siblings, six of whom he lives with.

But Judge Tompkins said Ratana’s explanation of the incident “seeks to minimise or downplay the seriousness of the offending.

 “This was a serious and unprovoked assault on a member of the police, who were endeavouring to stop an unrelated fight.”

He said Ratana chose to intervene in the melee in a way that put the officer’s life in “serious danger”.

He declined the application for a discharge without conviction and remanded him on bail to be sentenced in September.

Melissa Nightingale is a Wellington-based reporter who covers crime, justice and news in the capital. She joined the Herald in 2016 and has worked as a journalist for 10 years.