Major drug trafficker Saverio Zirilli was the victim of a fraud committed by police and to spend another day behind bars would be an injustice, his lawyer argues.
Zirilli is serving a 26 year prison sentence after admitting he was involved in major ecstasy imports and an attempt to bring cocaine to Australia.
But the man once represented by snitching barrister Nicola Gobbo has applied for bail, arguing he is likely to be acquitted of all charges.
Zirilli is challenging three convictions, all linked back to his bust as a major player in the 2007 import of 15 million ecstasy pills in tomato tins.
His involvement in any criminal activity, lawyer Mark Gumbleton says, can be traced entirely back to tips Ms Gobbo gave her Victoria Police handlers.
She told officers about the involvement of the Italians - "the boys from Griffith" - alongside her client Rob Karam and fellow trafficking big-gun Pasquale Barbaro.
Ms Gobbo told officers where they were staying. Officers arrived after the shipment had been seized, and after the group had checked out, but found the apartment had been booked in Zirilli's name.
He was under surveillance for the following year and arrested in August 2008.
"Properly analysed, everything that occurred ... was derived from intelligence provided by this officer of the court performing the impermissible joint role as an agent for the executive," Mr Gumbleton told Victoria's Court of Appeal on Tuesday.
He said it was remarkable that Ms Gobbo then represented him without telling him the entire case resulted from her treachery, he added.
Another of his lawyers may also have been a secret police snitch, he said, though police won't confirm or deny the suspicion.
"To leave this guy in custody for another day is to continue the same injustice, the same fraud, that has been perpetrated on him and this court by the executive," he said.
The separation of powers had been "utterly diminished" and made a "laughing stock", he said.
Prosecutors have opposed Zirilli's bail application, not accepting that the appeal case is strong.
Rae Sharp said commonwealth prosecutors and the Australian Federal Police - who prosecuted the matter - weren't aware that the source Victoria Police had for the bust was Ms Gobbo.
While they might have been aware there was a human source behind the tip-off, they had no obligation to identify the source, she said.
Zirilli still has nine years of his minimum sentence to serve before the possibility of parole, she said.
Mr Gumbleton said the prosecution response was "tepid" and appeared largely based on the fact there is no precedent. He said that was obvious.
"This has never happened before and the (Victoria Police) chief commissioner assures us this will never happen again," he said.
"This should never have occurred in the first place."
Justices Mark Weinberg and Stephen McLeish have reserved their decision.
Australian Associated Press