GUILTY: Shayd Robinson has been found guilty of the murder of Aaron Hadfield.

A young killer seen licking his victim's blood after stabbing him has followed in his father's and grandfather's violent footsteps.

Shayd Robinson, 21, was convicted of murder yesterday for stabbing Aaron Hadfield to death during a road rage attack in January last year.

His father, Tom Robinson, has also stabbed and killed someone, and his grandfather, Benjamin Robinson, almost killed a man when he shot him in the back during an armed robbery.

FAIRFAX NZ VIOLENT EXAMPLE: Tom Robinson, Shayd Robinson's father, outside the High Court at Wellington.

Shayd Robinson's victim died less than 20 metres from where his father's victim died, just across the intersection of George and Logie streets in Stokes Valley.

Robinson was found guilty by a jury of seven men and five women in the High Court at Wellington last night after 7 1/2 hours of deliberation. They rejected his claim that he was acting in self-defence.

Robinson admitted stabbing Hadfield once but said it was out of panic. It was alleged he licked the knife afterwards and said something like: "Your blood tastes sweet," or "I like the taste of your blood".

Robinson said he did not remember even seeing blood on the knife, let alone licking the knife or using those words.

His victim's father, James Hadfield, said the verdict was the right decision.

"As best as the law allows, justice was done. He was given a fairer trial than Aaron was.

"We'd like to thank the police and the detectives involved in bringing some sort of justice to Aaron. Whatever the result, it was never going to bring Aaron back."

It can also now be revealed that Axl Stark, 23, who was also involved in the attack, pleaded guilty to charges of assault and intentional damage. He was sentenced in November to four months' home detention.

He threw punches at Hadfield and kneed and kicked the driver's door of his car. The sentencing was suppressed until the end of Robinson's trial.

Robinson's murder conviction marks a horrific escalation of violence within three generations of his family.

In 1994, his father stabbed cousin Royston Hughes to death during a dispute over a car stereo. After a brief scuffle outside his flat, Tom Robinson went into his house for a blunt knife. Returning to the fight, he stabbed his cousin four times.

He claimed self-defence, saying his cousin had cut himself on the knife as he lunged forward, though a pathologist at the time said all four stab wounds went deeply downwards and the killer blow was delivered to the hilt. Robinson was convicted of manslaughter.

In 1981, Ben Robinson - who now goes by the name Chay Karnn - shot a pub manager in the back after ordering him to the ground during an armed robbery at the Grand National pub in Petone.

He took $12,000 and left, having blown a large hole in the back of Rick Bullock. Police initially labelled the incident "cold-blooded in the extreme". Ben Robinson had loaded and cocked the gun before confronting Bullock, who spent six weeks in hospital recovering from his injuries.

After three months on the run, Ben Robinson was caught and confessed. He was convicted of aggravated robbery and "injuring in such circumstances that, had death ensued, he would have been guilty of manslaughter".

Robinson's family declined to comment after last night's verdict.

Associate Professor Devon Polaschek, a forensic psychologist at Victoria University, said criminal behaviour was often passed between generations.

"It's very common for serious crime and violence to run in families. If people [think] that violence is OK or that violence is a way of solving problems . . . that sort of attitude or belief can be passed on."

Family history could also play a part in how the children learned to interact, she said. When both Shayd and Tom Robinson were children, their fathers were in prison for violent offending.

"Having weapons around the house, people get used to being around them. And there's a particular way of looking at the world . . . [where] you learn to misread hostility in others.

"So you see the world as a bit dog-eat-dog, and that's passed on down the generations, and that's why you might find yourself carrying a knife . . . and then you're much more likely to get into situations where someone's likely to get hurt."

Robinson, a first offender, has been remanded in custody for sentencing at a later date.

A VIOLENT LEGACY

BEN ROBINSON

On January 12, 1981, aged 25, he broke into the Grand National pub in Petone, wearing a balaclava and carrying a sawnoff shotgun. He pointed the gun at 42-year-old manager Rick Bullock and told him to open the safe, before ordering him to lie on the floor.

After taking $12,000, he shot Bullock in the back from close range, in what police initially called "a cold-blooded . . . premeditated attempt to kill".

Bullock suffered an 11cm-by-5cm wound to his lower back and spent six weeks in hospital.

Robinson remained on the run for three months, during which time he claimed to have spent all the money. He burned his clothes on Petone beach after the robbery and threw his shotgun into the sea at Makara.

On May 15, he pleaded guilty to aggravated robbery and discharging a weapon causing injury. The shooting was downgraded to accidental discharge after Robinson's confession. He was jailed for six years.

TOM ROBINSON

Fatally stabbed his cousin, Royston Hughes, during a dispute over a car stereo on February 20, 1994.

Hughes, who had a wife and three children, had visited Robinson's Stokes Valley home, annoyed that a car he had bought from him a month earlier for $400 had no stereo in it. After some shouting and shoving, Robinson, 20, went into his flat and picked up a small blunt knife with which he stabbed Hughes four times.

Robinson's father, Ben, found him cowering in a corner shortly after the stabbing, "shaking and rocking back and forwards like a child does".

Robinson was jailed for four years for manslaughter. He is now waiting to be sentenced for another stabbing incident, after pleading guilty on April 16 to wounding Brendon Oliver with intent to injure. The two men, who knew each other, had a fight in the doorway of a pharmacy, during which Robinson stabbed Oliver in the hip. He pleaded guilty on the basis of self-defence, though he admitted using a knife was excessive in the circumstances.

Robinson has had several convictions since killing his cousin. The most significant were possessing a firearm and ammunition in 2000, for which he was sentenced to periodic detention, and a Summary Offences Act conviction in 2005 for possessing a knife in a public place.

SHAYD ROBINSON

Stabbed and killed motorist Aaron Hadfield, 27, on January 26 last year, in Stokes Valley.

Robinson and Axl Stark were walking along the street as Hadfield drove past and, according to Robinson, almost struck Stark.

Hadfield stopped his car and Robinson and Stark threw punches at him. Robinson then reached into the car and stabbed Hadfield once in the chest. The blow struck his heart and lung.

Witnesses said they saw Robinson lick the blade of the knife and they heard him tell his dying victim that he liked the taste of his blood.

Hadfield, who had a partner and two children, was taken to hospital but died early the next day.