Grove Road murder: Crown admits Alan Hall shouldn't have been convicted because police hid vital evidence from jury

Auckland man Alan Hall spent nearly two decades in prison for murder, but the Crown on Tuesday admitted he shouldn't have been convicted because police deliberately hid vital evidence from the jury.

In a submission to the Supreme Court, Crown Law conceded what it calls "a substantial miscarriage of justice occurred" and that Alan's "convictions should be quashed".

He was 23 years old when he was charged with murdering Auckland father Arthur Easton in 1985. Easton was stabbed in a violent home invasion.

Alan spent a total of 19 years behind bars for that murder and was only released earlier this year. 

It's a crime he maintained he never committed, now at age 60, and the Crown has effectively agreed.

In a submission published ahead of his Supreme Court hearing on Wednesday, the Crown said it was effectively a trial gone wrong and a miscarriage of justice.

There are multiple examples of this, they added, like Police intentionally altering several witness statements, with one being adamant the killer was Māori - Alan is not - and it was concealed from his defence team. There was also the fact that the attacker was described as right-handed, and Alan is left-handed. 

Alan's brother Geoff Hall told Newshub that this latest development wasn't something the family was expecting.

He said there are so many more questions to be answered, including how it happened, why it happened, and why it's taken this long for Crown Law to admit it was wrong.

When it comes to compensation, that will be something Alan and his legal team will discuss and seek.

But the focus is now on Wednesday. Alan and dozens of family and supporters are here in Wellington for his Supreme Court hearing in the morning where it's expected that after almost four decades, his conviction will be quashed.