Indigenous rights advocates gathered in the Boorloo/Perth CBD on Monday to demand the closure of Unit 18 youth detention centre, which the WA Coroner described as "dangerous" in the inquest into the death in custody of Indigenous boy Cleveland Dodd.

Almost 100 people, led by Noongar Elder Uncle Ben Taylor Cuiermara, gathered outside the headquarters of the WA Department of Justice, which is under pressure to shut Unit 18 and improve safety in its youth detention system.

Chanting "no kids in cages", the snap action urged the Department to follow Coroner Philip Urquhart's recommendation to permanently shut Unit 18 due to its unacceptably poor levels of safety for juvenile inmates.

The rally came two weeks after Mr Urquhart completed his inquest into the October 12, 2023 death of Cleveland, a 16-year-old Yamatji boy.

In the early hours of that day, Cleveland was found unresponsive in his cell at Unit 18, the youth detention centre within Casuarina Prison, a maximum security adult facility. Cleveland, who had repeatedly warned Unit 18 staff he intended to take his own life, died after spending a week in hospital on life support.

The inquest into Cleveland's death concluded two weeks ago, with Coroner Philip Urquhart making 15 adverse findings against the Department of Justice and issuing 19 recommendations. Mr Urquhart described the conditions Cleveland endure at Unit 18 as "inhumane", said this youth detention centre remained dangerous, and called for its immediate closure.

Uncle Ben said Cleveland's death highlighted the broader plight of children suffering in detention.

"They are being treated like adults," he told the crowd. "Aboriginal young people deserve support, not punishment and torture. Unit 18 needs to be closed immediately. And not just replaced by a new prison with more bells and whistles."

Amnesty International Australia's Campaign Director Sarah Gooderman said Amnesty was calling upon the WA Government to cease the solitary confinement of children in custody.

"No child should ever have to experience what Cleveland did," she said, outside of the David Malcolm Justice Centre.

"Children do not belong in adult prison. They belong with their families. But we are here today because, instead of looking to community-led solutions, our government continues to fail children by resorting to punitive responses. It is important that we keep up the pressure on the WA Government to act upon the findings of the coronial inquest".

In handing down his findings, Mr Urquhart said the key fault was that Unit 18 was badly understaffed, and had been for years. Lack of staff contributed to inmates being kept inside their cells for prolonged hours.

Mr Urquhart said Cleveland had continually been denied fresh air, having been inside his cell for more than 22 hours a day during 74 of his 86 days at Unit 18. This heavy confinement would have made Cleveland desperate and despondent, he said.

Cleveland made repeated threats of self-harm during his almost three months in custody, but had been removed from the prison's list of "at-risk" youths before he died. Including less than 20 minutes before he was found unresponsive in his cell, where the CCTV cameras had been covered by toilet paper for many hours.

Mr Urquhart noted that in Unit 18 had been improved since Cleveland's death, but that it still remained unfit for children.

In response, the WA Department of Justice said it will review the Coroner's findings and "consider opportunities for further improvement" to youth justice. The Department stated that, since Cleveland's death, it had increased both the number of staff at Unit 18, and the amount of daily time its young inmates spend outside of their cells.

"Mental health and cultural supports have also been expanded," said Department Director General Kylie Maj.