Human rights law luminaries such as Geoffrey Robertson QC and Jennifer Robinson are set to bring the death of indigenous man David Dungay Jr in NSW custody in 2015 to an international audience.
Mr Robertson, Ms Robinson and Mr Dungay's mother Leetona and nephew Paul Silva will on Thursday address the media in Sydney on his death.
They aim to bring Mr Dungay's case "to the international community" amid the global Black Lives Matter movement galvanised by the 2020 death of George Floyd Jr at police hands in Minneapolis in the US.
Mr Floyd's death at the time sparked global protests.
The grouping also accuses the NSW government of failing to hold those responsible for Mr Dungay's death to account.
A 2019 coronial inquest into the 26-year-old's December 2015 death at Long Bay jail found the prison officers involved were not motivated by malicious intent.
Mr Dungay, a diabetic, because he was refusing to hand over a packet of biscuits he was eating.
Footage played during the inquest showed Mr Dungay repeatedly screaming "I can't breathe" to which one officer replied: "You're talking, you can breathe."
Mr Dungay was restrained by five prison officers and pinned down on the bed, and was seen spitting blood as he was taken from the cell.
After being placed in a second cell, he was injected with the sedative midazolam, but died an hour after officers first entered his cell.
