The Australian Federal Police should not be let "anywhere near" an investigation of fresh evidence casting renewed suspicion on the Calabrian Mafia for the assassination of Colin Winchester, according to a retired judge with extensive knowledge of the case.
The AFP was last week subjected to a blistering criticism for its failure to seriously and impartially investigate secret new information potentially linking the 'Ndrangheta to the 1989 killing of the assistant federal police commissioner outside his Deakin home.
John Dee, QC, retired Victorian judge and counsel assisting to the original inquest into Mr Winchester's death, believes an independent taskforce needs to be set up to properly look at the fresh evidence, utilising Victoria Police, a force with past intelligence involvement in the case.
A senior Victoria Police source said the creation of such a joint organised crime taskforce was feasible, albeit under an AFP lead, and said his state's detectives were skilled and well placed for such a job. "It can be done," he said.
Mr Winchester was said to have double-crossed members of the organised crime group, who believed the assistant commissioner had been paid off to guarantee protection over drug crops near Bungendore.
But 11 Mafia members, known as the "Bungendore 11", were later charged over the crops following a mission codenamed Operation Seville, which Mr Winchester had worked on in the early 1980s.
Links between the group and Mr Winchester's murder were only ever speculative, and extensive investigations failed to identify any individual suspect.
But the inquiry into David Eastman's conviction for Mr Winchester's murder this year unearthed new, untested claims that appear to have taken the Mafia theory further.
The evidence is highly sensitive and was heard in secretive and restricted hearings before inquiry head Acting Justice Brian Martin earlier this year.
Yet internal AFP documents showed the agency was reluctant to investigate the new claims.
They reveal the AFP had a policy of not looking at areas already investigated by Operation Peat, the original team on the Winchester murder.
They also reveal the AFP believed such an investigation would be an "unnecessary diversion" from the factual issues surrounding Eastman's conviction, and that public disclosure of the new evidence could result in public criticism of the agency.
Mr Dee said he believes the AFP are not the right agency to be investigating the 'Ndrangheta theory.
"I wouldn't allow anybody from the AFP to get anywhere near it, except on a peripheral basis," he said.
"I would think it'd be good to have a separate taskforce from [Victoria Police] to have a look at it, because they're well in touch with what's going on up there, and they're very experienced at what they do."
Eastman's long-term campaigner and former lawyer Terry O'Donnell also said the new claims need to be properly investigated, and supported a call for Victoria Police to look at the matter, given their background with the case.
Mr Dee, years before Eastman's trial, warned the AFP about their use of Victorian forensic expert Robert Collins Barnes.
He had worked with Mr Barnes on the trial for the infamous Russell Street bombing of the Victorian police headquarters in 1986, and believed Mr Barnes had not been independent and was trying to be the "star of the show".
It is now known that his warnings were accurate. Mr Barnes was found to be biased and his work deeply flawed in the report of the inquiry into Eastman's conviction.