The family of slain gangland drugs boss Carl Williams has made an 11th hour request to the Coroner's Court for an inquest into his murder in prison.
Williams was bludgeoned to death in the high security Acacia Unit at Barwon Prison in April, 2010.
His fellow cellmate Matthew Johnson is serving a life sentence for the murder.
Today, the Coroners Court received a letter from lawyers for Williams' father, George Williams, and his ex-wife Roberta Williams.
It requests the Chief Coroner Ian Gray investigate why the murder was not observed by video monitoring and prison guards.
It also asks why it took an estimated 30 minutes for guards to find him and why authorities didn't protect Williams after being warned his life was in danger.
"It is difficult to identity a death occurring in Victoria more deserving of an inquest than the death of Carl Williams. The death involves matters of high public importance," the letter stated.
However, the Coroner has indicated he is unlikely to grant the family's wishes.
Counsel for Corrections Victoria Ben Ihles argued it would be futile given at least four other separate investigations have been carried out into Williams' death.
"It is difficult to envisage a death in Victoria that has been more investigated, more reviewed, or more considered that the one we are talking about," he said.
Reviews have been carried out by The Office of Correctional Services Review, the Office of Police Integrity and the Victorian Ombudsman.
Mr Ihles told the court most of the issues raised by the family have been dealt with through 57 recommendations accepted by the Department of Justice.
Coroner Gray said it appeared the matter had been thoroughly investigated already.
He reserved his decision.