A top Victorian policeman who made a name for busting notorious Melbourne underworld figures has been found guilty of leaking confidential information about a secretive anti-corruption investigation.
Commander Stuart Bateson was found guilty on Friday of three charges of disclosing restricted matters.
After several weeks of hearings, magistrate Simon Zebrowski found Bateson had "made it abundantly clear" to a junior officer that he had been questioned during a confidential IBAC hearing.
The Independent Broad-based Anti-corruption Commission probe was looking into allegations of improper influence into an investigation by Taskforce Salus, which examines harassment and predatory behaviour in the force.
In 2018 Bateson was called to give evidence at a hearing examining suggestions of sexual misconduct within the force and was served with confidentiality notices, requiring him to keep the details a secret.
But he was accused of sharing detailed information about the investigation with a junior colleague over three months.
Mr Zebrowski found that between August and October 2018 Bateson had disclosed to the junior officer the subject matter of the IBAC investigation, evidence given to or obtained by the investigation, and that he had been examined.
The woman, who cannot be identified but gave evidence during the hearing, described Bateson as "nervous and fidgety" during a conversation with her in August 2018 when he told her he had been called in and spoken to.
She described Bateson as "talking in riddles".
Bateson had claimed the young officer got the information from other sources including the Victoria Police "rumour mill", media outlets and knowledge from previous conversations with him.
Mr Zebrowski said Bateson's lawyers claimed it was all "cobbled together in a Machiavellian plot to destroy" him.
But the magistrate rejected Bateson's defence, finding that the woman's evidence had a ring of truth to it and was unlikely something that a liar would concoct.
But Bateson's evidence was unconvincing and a "dull thud" he said.
He believed Bateson had "tied himself in knots" during the evidence.
"I have absolutely no doubt that Mr Bateson's motivation for going to (the junior officer)... was not out of any noble sense of self-reflection, but rather out of the basic human instinct for self-preservation," he said.
Lawyers requested six weeks to put together submissions on sentencing.
Bateson has held several high-profile positions within Victoria Police, including as a senior member of the gangland busting Purana Taskforce.
He was the inspiration for a lead character, played by Roger Corser, in the television series Underbelly, based on Melbourne's gangland wars.