Alo Ngata's family seeking justice two years after his death in police custody

Alo Ngata man was tasered restrained and put in a spit hood before he died in hospital in July 2018. Photo / File

Two years on from her son's death in police custody, Alo Ngata's mother wants someone to be held to account.

The 29-year-old died after a violent struggle with police, during which he was tasered multiple times, restrained and put in a spit hood.

Handcuffed, alone, lying face down with his ankles bound and his face covered, Ngata stopped breathing in a police cell in July 2018. He died in hospital three days later.

Two internal police investigations concluded that no person was criminally culpable for Ngata's death.

In a statement, police confirmed no officers had been subject to any internal employment processes, given the finding of the police investigation.

But Alofa Ngata is still seeking justice for her son, who died before he would get to meet his first child.

"I want someone to be held to account," she told TVNZ's Sunday programme.

"I didn't want to see my son die like he did."

Marie Dyhrberg, QC, told the Sunday programme that the public had a right to know if mistakes were made in the hours leading up to Ngata's death.

Alo Ngata man was tasered restrained and put in a spit hood before he died in hospital in July 2018. Photo / File

Ngata was arrested at a Freemans Bay address around 1pm on July 4, 2018, following reports he'd viciously assaulted an elderly man.

His face was covered in blood. Minutes earlier he'd leapt in the air, hands behind his back, plunging himself head-first into the concrete ground.

Then he got up and dived again, before head-butting the window of a parked car.

"He was saying there were demons in his head," a witness told the Herald at the time.

From the Eagle helicopter police saw Ngata kick the 76-year-old victim in the head "five or six times, essentially until he was unconscious," Auckland City District Commander Superintendent Karyn Malthus told media in 2018.

The victim, Mike Reilly, can no longer walk unaided since the attack.

Now 78, he told the Herald he was "bedridden" in a Lynfield rest home, with little hope of recovery.

Reilly and his family are now fighting ACC for support following the attack - which left him suffering a concussion, contusions, a busted knee and broken clavicle, which swelled so badly doctors feared it would cut off his breathing.

Officers attempting to help Reilly, crumpled on the concrete after the assault, were blocked by Ngata, police said.

Mike Reilly says he has not been able to walk since the attack. Photo / File

When Ngata lunged at officers he was tasered several times, pepper sprayed and pulled to the ground using force.

According to police policy, following the use of pepper spray on someone officers must ensure that the person's face remains uncovered and they are not left to lie face down.

A witness told the Sunday programme Ngata repeatedly said he could not breathe under the weight of multiple police officers, before a spit hood was pulled over his head.

Used by police to stop a person spitting, the top half is made out of dark mesh while the lower part is a white sheet that prevents spitting.

But police guidelines state spit hoods should not be used on someone who is bleeding from the mouth or nose, or anyone having difficulty breathing.

Ngata's spit hood was incorrectly applied, with the fabric pulled over his mouth, nose and eyes.

Alo Ngata man was tasered restrained and put in a spit hood before he died in hospital in July 2018. Photo / File

He was taken to the Auckland City police station where officers say his condition deteriorated.

Officers found him face down, the spit mask still covering his head. He wasn't breathing.

Ngata was given CPR and taken to Auckland Hospital on life support, which was switched off three days later - the earliest his family could return from Tonga.

In a statement, police said Ngata's death was still under an active IPCA investigation and Coronial proceedings.

"Police conducted a critical incident investigation which examined criminal culpability.

"It has been determined after consideration of expert evidence and independent legal advice that legal causation for Mr Ngata's death was not established and on that basis no person is criminally culpable for Mr Ngata's death.

"Police takes the management and care of those in custody very seriously and the death of Alo Ngata is an absolute tragedy."

A national review on the transport and custody of prisoners was ongoing and Ngata's death would form part of that.