It was rumoured that he helped to plant a bomb under the car of Liborio Benvenuto, the "Melbourne Godfather", in May 1983.

Sumner was also an associate of Rocco Medici and Giuseppe Furina, two Melbourne men whose mutilated bodies were found dumped in the Murrumbidgee River in May 1984.

Many also believed that in 1988 he provided the gun used to kill Giuseppe Arena outside his Bayswater home.

Sumner was connected to several Italian crime figures and apparently a close friend of Arena's.

Sumner and Arena met in jail when Arena was serving a sentence for killing his wife's lover.

Police said Arena used his family home as surety for a bail application for Sumner in 1982.

Arena had been close to Liborio Benvenuto who died on June 10, 1988.

Arena was considered as a replacement for Benvenuto.

Police said Arena retired from the insurance business within weeks of Benvenuto's death.

But he became terrified that he was marked for death and approached his friend Sumner, who provided him with a pistol for protection.

But just a few days before his murder Joe gave it to another friend.

It remains a mystery as to why Arena feared for his life and why he must have thought the threat was over, days before his murder.

Arena was killed on August 1, 1988.

Sumner was charged with trafficking $2 million of heroin and was acquitted.

He was seen drinking with members of the jury in a hotel near the court that night.

He was silly enough to park it in the driveway of his double-storey Avondale Heights home at night.

Drug squad detectives went to his house to find the stolen car so that they could revoke his bail.

The car was in the drive, as expected, but there was a bonus.

Walking up the driveway, Detective-Sergeant Wayne Strawhorn could hear an industrial pump operating and see water pouring out of a hose poking from the garage.

His experienced nose picked up the odour of amphetamine chemicals through the slightly opened door.

Some drug squad operations can take years of detailed investigation; others can be laughably easy.

In this case, police simply walked up, opened the garage, grabbed their man and a truckload of evidence.

Sumner was "done cold".

The case was watertight and the exhibits were under lock and key - or so the detectives thought.

Sumner was experienced enough to know that even the best lawyer couldn't save him.

He needed a break, and it came from another criminal who offered to sell information that would destroy the police case.

It is believed Sumner paid several thousand dollars for the red-hot mail.

In return, he was told to demand that all the drugs seized in his case be retested.

The results, he was assured, would surprise.

But Sumner was convicted on three counts of drug trafficking in October 1992 and sentenced to nine years with a six-year nine-month minimum.

Sydney police secretly travelled to Melbourne early in 1993 to interview Sumner.

After the interview, the NSW Government approached the Victorian Office of Corrections with a request that Sumner be transferred concerning "justice issues".

Sumner was given permission to continue serving his prison term in NSW rather than Victoria.

It was believed he had agreed to talk to NSW detectives about allegations involving organised crime and corruption.