Warning: Graphic content.

A son accused of murdering his abusive father, compared to the Once Were Warriors character Jake "the Muss" Heke, says he was defending himself and his family when he stabbed his dad to death.

The trial of the young man, who has interim name suppression, began today in the High Court at Auckland before a jury and Justice Alisa Duffy.

Several suppression orders prevent the Herald from revealing certain details about the killing, which occurred in South Auckland last year.

During his opening address, Crown prosecutor Gareth Kayes told the court the defendant stabbed his father six times, including a fatal strike to his chest.

The 27cm-long knife, with a 14cm blade, was plunged 11cm deep into the father's body during the short but violent confrontation, Kayes said. The knife penetrated the father's heart.

The accused, who is in his 20s, accepts killing his father, in his 40s, but will argue his actions were justified as he attempted to protect himself and others.

His defence team described the father as "a monster" who "terrorised his family, both emotionally and physically". The circumstances of the case were also compared to the infamous New Zealand film depicting horrific domestic violence, Once Were Warriors.

The father, the defence claimed, lived the lifestyle of the abusive character Jake "the Muss"

Crown prosecutor Gareth Kayes. (Photo / Greg Bowker)

The court heard, from Kayes, that the son's parents had been together for about two decades and had moved to Auckland with their children.

However, the prosecutor explained, the father was a drug user and violent towards his wife and other members of his family.

"A bad man," Kayes said. "A person who was a wife beater and a drug user."

The family had moved to Auckland to rebuild their lives, with the hope it would be absent of a traumatic home environment, but the father failed to curb his violent nature, Kayes said.

On the night of the alleged murder, the father had seriously assaulted his wife, punching her several times to the face and kicking her.

Attempting to seek refuge, she took one of her young children and fled to her son's home, the accused.

Kayes said the father then made his way to his son's home and a heated argument ensued, with the dad yelling from the driveway.

The son attempted to confront his father, but other family members intervened and stopped the young man from going outside, Kayes said.

The son's partner called police, the doors were locked and curtains drawn. The family believed the father had left the property.

However, Kayes told the jury, before police arrived, the son left the security of the home's walls and was clutching a knife.

Soon after, family members found the father lying on the deck, stabbed, and bleeding.

Justice Alisa Duffy is presiding over the trial. (Photo / Greg Bowker)

When police arrived the son was taken to a police station where he gave a lengthy statement to officers.

During the interview, which will be played before the court during the trial, the accused told police his father had come "out of the dark" and punched him on the left side of the head, knocking him off the deck.

The young man admitted using the knife to stab his father - twice.

"Only two people saw what happened outside on the deck," Kayes said.

"While the defendant is the only one alive who knows what happened on the deck, there is other scientific evidence that the Crown says you will want to take into account."

A pathologist is expected to testify that the father had four stab wounds to his torso, one to the left side of his head and one to his thigh.

The fatal wound, Kayes said, was to the centre of his chest and 11cm deep. It had nicked the right lung and penetrated the heart.

A strike to the left side of the father's head was 6.8cm deep and had pierced an artery, which the pathologist concluded contributed to death, Kayes said.

A doctor who examined the defendant, who Kayes said was "virtually unscathed" after the fight, will be also called as a witness.

"Don't get me wrong here, [the father] had been nasty and hostile to the defendant and his family, particularly to [his wife]," Kayes said.

"[But] was his use of force proportionate and reasonable to the threat?"

Kayes proposed the jury should acknowledge any prejudice they will feel towards the father and the sympathy they may have for the defendant, his mother and family.

But, the prosecutor told the jury to put those emotions aside.

"A murder is still a murder, even if it is unplanned," he said.

Defence counsel Denise Wallwork. (Photo / Greg Bowker)

The defence team, led by Denise Wallwork, began with an opening statement by junior counsel Elaine Ward.

There was no doubt her client had acted in self-defence, a complete defence to a murder charge, she said.

The family dynamics and characters of the case will be played out during the trial, including how the father was an abuser of not just his family but also of cannabis and methamphetamine.

The trial continues.