Warning: this story contains the name and image of a person who has died, and disturbing details.

The death of a 32-year-old Indigenous man who died in his cell as staff watched due to flawed protocols has been labelled a "preventable tragedy" by the coroner.

Yorta Yorta and Gunaikurnai man Joshua Kerr died while on remand on August 10, 2022, at the privately run Port Phillip Prison in Victoria, as staff watched him scream in pain via CCTV.

In the hours before his death, Mr Kerr lit a fire in his prison cell and was transferred to St Vincent's hospital for treatment of burns on his hands and arms, accompanied by Tactical Operations Group (TOG) members.

However, after a period at St Vincent's where Mr Kerr - who had previously disclosed he had taken methamphetamine - became agitated and rejected medical attention, two TOG staff members cancelled the escort before he was formally discharged.

On Monday, Coroner David Ryan found Mr Kerr's death was likely preventable.

"Josh would have very likely survived had he remained in hospital," Mr Ryan said.

"Josh required further assessment and treatment in the ED at SVHM [St. Vincent's Hospital Melbourne] for his ABD [acute behavioural disturbance] in the context of his disclosure of having used ice earlier in the day.

"The medical staff in the ED lost the opportunity to provide this further assessment and treatment as a result of the escort being cancelled by the TOG officers without meaningful consultation."

Back at Port Phillip, he was placed in a cell with the on-site medical unit which could be viewed in real-time via CCTV. TOG instructed the cell to remain closed unless their own staff were present.

Mr Ryan said Mr Kerr collapsed to the floor at 7:43pm, with his last movement seen at 8:01pm.

A "Code Black" was called nine minutes later; however, it took a further eight minutes for TOG officers to arrive at Mr Kerr's cell.

Despite paramedics being called, he was pronounced dead at 8.41pm.

"There were a number of periods of time on 10 August 2022 where more decisive, considered and effective action by staff would have altered the care and treatment received by Josh in a way that most likely would have prevented his passing," Mr Ryan said.

The court had previously heard Mr Kerr was "visibly unresponsive" for 17 minutes before receiving medical treatment, having called out "I'm dying" with no action from prison staff.

His behaviour was described by counsel assisting the coroner, Rachel Ellyard, as "distressing and bizarre."

A panel later determined Mr Kerr died from the high level of drugs in his system.

Mr Ryan stated Mr Kerr should not have been removed from hospital before he was formally discharged by hospital staff.

"This prevented Josh's medical treatment being finalised and deprived the medical staff of a further opportunity to assess Josh and properly document a plan for his future treatment," he said.

His doctor was not aware that Mr Kerr had left the emergency department, and "in fact thought that he was likely to be admitted by the plastics team for treatment in relation to his burns".

"Josh's passing was a preventable tragedy which has devastated his family and community," Mr Ryan said.

He noted more decisive and considered action by the staff would have most likely prevented his passing, but acknowledged there was always the chance medical staff would have cleared Mr Kerr to go back to Port Phillip even if TOG officers had not cancelled the escort.

He also argued Mr Kerr should have been taken back to hospital as his condition worsened throughout the day.

Mr Ryan said TOG officers were under the impression Mr Kerr only had a hand injury - for which he had refused treatment - rather than also suffering from the effects of methamphetamine ingestion.

He stated the case saw a "disproportionate focus on security concerns".

"TOG directions should not prevent a prisoner from receiving medical treatment," he said.

In his recommendations, Mr Ryan recommended more training for prison staff to recognise the impact of drugs on prisoners' health, as well as training both for medical and prison staff to know their exact roles and responsibilities when it comes to treating an inmate.

Outside of court, Mr Kerr's mother, Donnas Kerr, said: "The Coroner found today that Josh's death was preventable. How many times do we have to hear these words before we take Aboriginal deaths in custody seriously?"

"The coroner found that the Correctional and medical staff at the prison should have known my son was dying. For hours, they didn't call, even go into his cell, or call an ambulance," she said.

"This is what is wrong with our system - the lack of care and compassion for human life, for Aboriginal lives."

Last week the Victorian government announced the closure of Port Phillip prison and Ms Kerr said whilst she was happy at this decision, if it "had closed down two years ago, maybe my son would have been alive today".

Ms Kerr also thanked the coroner for his findings, and the law firm Robinson Gill.

Robinson Gill's Principal Lawyer, Ali Besiroglu, who had represented the family through the inquest, confirmed to National Indigenous Times that they will commence a civil action on behalf of the Kerr family against those responsible for the circumstances surrounding Mr Kerr's death.