Carl Williams first to suspect his lawyer was an informer

Murdered underworld boss Carl Williams was one of the first to suspect he was being double-crossed by his own lawyer, whose role as police informer 3838 has potentially compromised dozens of convictions and sparked a royal commission.

A hand-written letter obtained by The Age reveals Williams complained to an associate that his trusted lawyer had struck a deal with police to turn a close friend and drug-dealing hitman against him.

Carl Williams in 2004.Credit: Jason South

The letter was sent in 2006, when Williams was on remand in Barwon Prison awaiting trial on murder.

The hitman, who cannot be named, gave detailed statements against Williams and drug lord Tony Mokbel, telling police about how they had formed a criminal alliance, who they had targeted for murder, and which corrupt police had provided inside information.

The hitman-turned-informer, who is referred to in court documents as Witness B, received a heavily discounted prison sentence which was served at a secret location.

"[The lawyer] admitted .... that [she] told or advised [the hitman] to go with the police and make statement against me," Williams wrote from his prison cell in the Acacia unit.

He went on to claim the lawyer visited Witness B and advised him to strike a deal with police.

Williams wrote that he believed she was a registered informer who had been used to end Melbourne's brutal underworld war.

"There is a lot more stuff that I cannot say at the moment, but believe me I am 100 per cent right, as much as I don't want to think I was," Williams wrote.

Williams relayed his suspicions to then wife Roberta, who sent a series of vicious text messages to the barrister, known to police as Informer 3838 and identified in court documents by the acronym EF.

A legal source said the messages would make "a seaman blush".

"She could be quite a tough lady, Roberta. She ran amok on [the lawyer] because she believed, maybe rightly, that she was informing," he said.

The decision by Victoria Police to use Williams' former lawyer as a registered informer will be the subject of a royal commission announced on Monday by Premier Daniel Andrews.

The first page of Carl Williams' letter.

The second page of Carl Williams' letter.

Meanwhile, dozens of her former clients are preparing appeals, amid revelations their trials have been seriously compromised.

Several convictions are now in doubt, including that of drug lord Tony Mokbel and those obtained in the infamous "tomato tins" drug case, namely Calabrian mafia boss Pasquale Barbaro and trafficker Rob Karam.

The lawyer had previously denied being a police plant, but has repeatedly been warned that her life is in danger. She has resisted requests to be placed in the secretive Witness Protection Program.

She also received a $2.88 million settlement from police, which was announced on Grand Final Eve in 2012 in an apparent bid to avoid publicity.

In a withering judgment published on Monday, the full bench of the High Court slammed the barrister and Victoria Police.

"The lawyer's actions to act as counsel for the convicted persons while covertly informing against them were fundamental and appalling breaches of [the lawyer’s] obligations as counsel to her clients and of EF's duties to the court," the judgment read.

"Likewise, Victoria Police were guilty of reprehensible conduct in knowingly encouraging [the lawyer] to do as she did and were involved in sanctioning atrocious breaches of the sworn duty of every police officer to discharge all duties imposed on them faithfully and according to law without favour or affection, malice or ill-will."

Williams was murdered in April 2010 in a secure secure unit of Barwon Prison after he made a deal with police to betray fellow criminals in exchange for a extraordinary concessions from Victorian authorities – which had already agreed to pay for his daughter Dhakota's school fees.

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