On the night of Sunday, 13 October 1985, a 52-year-old father of five, Arthur Easton, was stabbed to death in his Papakura home.
His teenage sons, Brendan and Kim, were injured in the attack but survived.
The boys initially described the attacker as a strong six-foot (1.83m) 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, 1.7m Pakeha with learning difficulties.
Hall has always maintained his innocence. More than 30 years later, he is still in prison.
Now Mike Wesley-Smith can reveal a startling development in the story of Alan Hall, one which offers new hope in his decades-long struggle to clear his name.
Watch the video for the full story.
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