The number of Indigenous people who have died in custody in Australia has hit the highest level since records began in 1980.

New data from the Australian Institute of Criminology showed that 33 of the 113 individuals who died in custody in the 12 months leading to June this year were Indigenous, up from 24 compared to the previous year.

Aboriginal and Torres Strait Islander people represent more than one-third of all prisoners in Australia, despite making up less than four percent of the country's population.

These alarming figures come over three decades after a landmark inquiry into Indigenous deaths in custody which made hundreds of recommendations aimed at addressing this endemic issue.

Of the 33 Indigenous deaths in custody between last July and this June, 26 occurred while the individuals were in prison custody, an increase from the 18 recorded in the previous 12 months. One individual died in youth detention, and all except one of the deceased were male.

Furthermore, six Indigenous deaths occurred in police custody, where individuals died during detention or while being restrained by police forces.

The main causes of death among Indigenous detainees were classified as 'self-inflicted', followed by 'natural causes', with hanging being the cause of death in eight cases.

New South Wales recorded the highest number of Indigenous deaths in prison custody with nine, followed by Western Australia with six. Queensland, South Australia, and the Australian Capital Territory each reported three deaths.

The NSW state coroner has described the rising number of Indigenous deaths in custody as a "profoundly distressing milestone" and called for independent and careful scrutiny of these cases.

Recent comments from specialists highlight that the figures reflect a national crisis needing urgent action and leadership, lamenting the stagnation of progress since the findings of the royal commission in 1991.

After the commission, over 600 Indigenous people have died in custody, amplifying calls for comprehensive reforms in the justice system to protect vulnerable populations.