Former Victoria Police assistant commissioner Jeff Pope has been named as the source of a 2014 leak revealing lawyer Nicola Gobbo was an informer.
Homicide detective Sol Solomon recorded the allegation in a diary note after he was contacted by Herald Sun journalist Anthony Dowsley, who broke the Lawyer X story that year.
Dowsley contacted Mr Pope in March 2014 to ask about Ms Gobbo's claims she'd had a sexual relationship with the then-senior Victoria Police officer.
Mr Pope then contacted Mr Solomon, a royal commission into her informing heard on Tuesday.
"Pope disclosed to (Dowsley) that F was a registered human source," Mr Solomon's note said, referring to Ms Gobbo who was known as Witness F in a police prosecution against former officer Paul Dale.
Those notes were then given to other senior police, including Inspector Boris Buick and assistant commissioners Steve Fontana and Mick Frewen.
Mr Pope was one of the first witnesses called in the royal commission, where he denied allegations of a sexual relationship with the informer after recruiting her for a second stint in 1999.
He's due to return to the inquiry later this week, in the final days of public hearings.
Claims Mr Pope was the source of the leak were put to former assistant commissioner Stephen Leane on Tuesday.
Mr Leane pressed anti-corruption body IBAC to investigate the leaks in April 2014, but they refused.
He admitted it would be a "serious breach of conduct" if Mr Pope did what Mr Solomon recorded.
Mr Leane also told the inquiry the investigation into Ms Gobbo's informing had been "death by a thousand cuts".
The anti-corruption body IBAC denied his initial request for investigation in April 2014, but commissioned the Kellam report three months later investigating the conduct of police.
It was left for police to investigate whether cases had been impacted by their conduct or Ms Gobbo's informing, and whether it should have been disclosed to prosecutors or courts, he said.
"These oversight agencies were doing limited slivers of the broader issues," he said, saying the same was occurring with the royal commission.
"This is like death by a thousand cuts - we're off in that direction and we'll get a report into this sliver, but we've still got the underlying issue that isn't resolved," he said.
Public hearings into Ms Gobbo's informing are due to end on Friday, with a small number of policy-related hearings scheduled for April.
Commissioner Margaret McMurdo is due to hand down her findings on July 1.
Australian Associated Press
