The family of an Iranian refugee who died on Manus Island fear the Australian government could avoid responsibility for his death because it is being investigated in Papua New Guinea.
The body of Hamed Shamshiripour was found near refugee accommodation in the township of Lorengau on Manus Island last week.
Australian authorities were earlier told the 31-year-old's mental health was deteriorating and that he was at risk of harm.
His death is being investigated by PNG authorities, who are treating it as a suspected suicide, and a report will be prepared for the coroner.
But laywer George Newhouse says the 31-year-old's family want the investigation to be held in Australia.
"The family are concerned that the federal government will use the offshore jurisdiction of a PNG inquest to hide their complicity in Hamed's death," he told AAP on Wednesday.
"In particular, an Australian coroner would be able to call senior bureaucrats for cross-examination and obtain government documents."
Australia's immigration department has been contacted for comment.
Readers seeking support and information about suicide prevention can contact Lifeline on 13 11 14.