Two families have asked a coroner to release police Eagle chopper footage showing the brutal attack and subsequent arrest of a violent, deranged man who later died in police custody.
The footage is subject to a non-publication order, which the families have applied to have overturned.
"We felt like that would be the only way to get people to listen," said Tom Reilly, whose father Mike barely survived the unprovoked attack.
Alo Ngata, 29, beat the pensioner and former country musician to within an inch of his life on a Freemans Bay street in July 2018.
The heavily built Tongan factory worker and meth user attacked Reilly without warning, repeatedly kicking and stomping on his head.
The savage beating lasted several minutes and only ended when police Tasered Ngata four times, pepper sprayed him twice, and restrained him with handcuffs, leg restraints and a spit hood before taking him into custody.
A witness claimed to have heard Ngata say "I can't breathe" during the arrest. He died in hospital three days later when life support was switched off.
An Independent Police Conduct Authority report, released on Thursday, said a post-mortem examination found Ngata died from asphyxiation.
The report ruled the use of police force was reasonable, but found "multiple failures" by officers involved in Ngata's arrest.
This included failing to realise the spit hood had been applied incorrectly, and not taking immediate steps to check on his welfare after Ngata was left alone and motionless, facedown on the floor of the cell.
No officers were found criminally culpable. A coroner is yet to rule on Ngata's death.
The Herald can reveal that Ngata's grieving family have now applied to the coroner to release footage of the attack. It's understood the family, who have criticised police for their role in Ngata's death, have already viewed the footage. Tom Reilly told the Herald his family were also keen to access the footage, but for different reasons.
They hoped a visual record of the beating Ngata inflicted on Mike Reilly would help convince ACC that his horrific injuries were the reason he could no longer walk.
Though he could walk before the attack and was living independently, the 78-year-old is now "bedridden" in a Lynfield rest home and unable to walk unassisted.
Despite Reilly spending a month in hospital after the attack, doctors say his walking problems are "degenerative wear and tear" and blame nerve damage from years of heavy alcohol use.
ACC refused further treatment last year, saying "this cannot be funded ... as it's not accident/injury related" - before backing down when the family brought in lawyers.
After reading about Reilly's case in the Herald, an expat Kiwi neurologist based in the United States contacted the family and offered to review Reilly's files.
After assessing medical records and witness accounts, Quentin Durward wrote to Tom Reilly this month, saying though there were signs of degeneration, evidence of the attack was "compelling".
"I can only assume that the head injury that resulted from the assault did in fact cause an injury to his brain that has resulted in this permanent deficit.
"I am of the opinion that, more likely than not, Mike did have a brain injury from the assault, and that injury is a significant factor in his inability to walk."
Tom said Durward's opinion had buoyed his father's hopes, and the family were now going back to ACC.
"It's exciting to finally have someone giving us an opinion that aligns with common sense."
They now wanted compensation for the time Reilly has not received proper treatment and a funded programme of rehabilitation.
Tom believed the footage would provide compelling visual evidence to present to ACC.
"Without that kind of evidence it's just a whole lot of doctors' notes on a piece of paper. It doesn't have the same impact as actually seeing what happened that day."
A coronial services spokesman confirmed the Ngata family had requested the non-publication order relating to the Eagle video footage be lifted, which was supported by Reilly's son Tom.
"The coroner is awaiting submissions from counsel for each party before making his decision. The non-publication order remains in force in the meantime."
Police have also made a submission but said it would be inappropriate to release it to the Herald while the coroner was deliberating.