Cleveland Dodd was found unresponsive in the early hours of October 12, 2023, inside his cell in Unit 18 at Perth's Casuarina Prison, becoming the first juvenile to die in detention in Western Australia.
The 16-year-old had made multiple threats to self-harm and numerous requests for medical treatment and drinking water in the hours before he was discovered and taken to hospital.
He died eight days later.
The only nurse working that night, Fiona Bain, broke down in the witness box as she addressed the boy's family.
"As I reflect on Unit 18 I see it as a leaky boat," she said while sobbing.
"No matter how much you patch it up you were destined to see what happened on the night of the 11th and 12th of October was a complete tragedy.
"I would like to say to the family I am so sorry for your loss."
She said the unit's medical staff were "completely dedicated" to providing the best health care in "the most challenging environment".
Coroner Phil Urquhart noted Ms Bain had also apologised outside court and he agreed with her assessment that Unit 18 was a leaky boat.
"From the evidence I have heard that's an overwhelming understatement regarding the situation there," he said.
He commended her efforts in Cleveland's cell when she and corrections officers partially resuscitated him before paramedics arrived.
The coroner also said he would likely find that he was satisfied with Ms Bain and the custodial staff's efforts to save the teen.
A prison nurse who tried to save teen Cleveland Dodd has sobbed while apologising to his family. (HANDOUT/SUPPLIED)
Ms Bain, who gave evidence for two days, told the inquest the situation was so dire that every detainee in the facility should have been included in a system that rates their risk of self-harm - known as the At-Risk Management System - and provided extra monitoring, but they weren't.
She said detainees made so many threats to inflict injuries to themselves, up to 50 per day, that it was impossible to implement the Department of Justice policy because of the staffing levels and infrastructure.
Their welfare was monitored through officers physically checking on detainees by looking through a locked door and using in-cell cameras, which the boys often covered with tissue paper to block the view.
The inquest heard that when this was repeatedly done, detainees were sometimes "chained" or restrained inside their cell for several hours.
Ms Bain also told the coroner senior officers could withhold medication from detainees if they had been violent towards staff, and it could become a "battle of wills" with custodial staff as she sought to provide care.
When permission was granted, Ms Bain said the medication was generally pushed under the detainee's door on a piece of paper.
She also said that if there was no drinking water in the detainee's cell, which was common, it would generally not be administered because that would require staff to open the cell door.
Prescription medication was generally handed to detainees in the early evening when their cell doors were unlocked to deliver a meal, under the watchful eye of a prison officer and a youth custodial officer carrying a shield.
Cleveland made eight threats to harm himself and six requests for Ms Bain and Panadol before he was found motionless in his cell.
The nurse said she has no recollection of youth custodial officer Nina Hayden telling her Cleveland had requested medical help on three occasions in the hours before he hurt himself.
She also said she was unaware that Cleveland's bid for bail had been adjourned earlier in the day or that he had made threats to harm himself, saying it would have been helpful and she would have gone to see him if she'd been told.
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