On the night of Sunday, 13 October 1985, 61-year-old father of five Arthur Easton was stabbed to death in his Papakura home.
His sons, Brendan and Kim, were injured in the attack but survived.
The boys initially described their attacker as a strong six-foot Maori man. Police searched for this suspect for months but in the end, the man arrested, charged and incarcerated for Arthur's murder was Alan Hall - a slim five-foot-seven Pakeha with learning difficulties.
Alan has always maintained his innocence. More than 30 years later, he is still in prison.
This is the story of the murder of Arthur Easton and the arrest of Alan Hall, a man with no alibi or answers.
But it's also a story about our system of justice - the power and trust we give to police and prosecutor and their ability to find the truth.
The night of the murder:
The facts of what happened on the night of the murder are still contested.
Here's what we know happened for sure.
Sixteen-year-old Papakura High School student Brendan Easton was studying in his room.
His dad, Arthur, was watching TV 20 feet away in the living room, and his older brother, Kim, was in his own bedroom.
Brendan heard the back door click. He went to investigate and discovered an intruder in the spare room by the back door. He shoulder charged him to the bed and then retreated into the hall, screaming for help.
Arthur Easton rushed to the hallway to try and restrain the intruder.
Kim later told detectives that he also rushed over and punched the stranger. He smashed a squash racquet down on the offender’s head until the frame snapped.
During the attack, Arthur Easton was stabbed multiple times.
The offender managed to escape, leaving behind three pieces of evidence – a bloodied bayonet, a woollen beanie and a single muddy footprint.
Brendan called emergency services at 8:05pm.
Arthur died at approximately at 8:35pm.
An unlikely suspect:
On September 27 1986, Alan Hall was found guilty of the murder of Arthur Easton. Prosecutors said Alan broke into Arthur's house, fought with him and his teenage sons in their hallway, and stabbed Arthur to death before escaping.
For three decades, Alan has maintained his innocence.
Alan has been described as "simple" – not as mentally alert as others. On the evidence statements Alan signed the day police first questioned him, he spelt his own name incorrectly on every page.
Growing up, Alan's mum Shirley said he was a frail child – awkward and shy. Police described him as cold and callous.
On the night of the murder, Alan says he set out for a walk – something he did often to help deal with the grief of his father's recent death. He walked the streets of his neighbourhood for around 35 – 40 minutes, came home and listened to the radio. He had a shower, and went to bed – in the sleepout he shared with his brother Greg.
Police say Alan's evening panned out very differently. They say Alan Hall had not just gone out for a walk, he had gone to Grove Road to commit murder.
Grove Road was created in partnership with Newshub Nation, which is made with help from NZ On Air.
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