Nicola Gobbo may have turned informer because she felt guilty about not preventing a double murder, a former Victorian detective believes.
Gavan Ryan headed the taskforce investigating the murders of police informer Terence Hodson and his wife Christine in 2004.
"My hunch is she knew something was going to happen to them," he revealed at an inquiry into police use of informers on Wednesday.
"She regretted not doing something and decided to 'roll over'."
Ms Gobbo, now known as Lawyer X, was registered as a police informer in 2005, a year after the Hodsons were murdered execution-style in their Kew home.
Former policeman Paul Dale and hitman Rodney Collins were charged with the murder, although charges were later dropped.
Mr Hodson had turned informer against Mr Dale over a burglary on a drug stash house.
Charges against Mr Dale in that case were dropped when the Hodsons were killed.
Mr Ryan said he once asked Ms Gobbo directly at a dinner with other police and handlers what her motivation for informing was, but she fobbed him off.
Commissioner Margaret McMurdo acknowledged Mr Ryan's theory was just that - a theory.
"But it's an interesting one," she said.
The night of the Hodsons' murders Ms Gobbo had dinner with a man who was later identified as a suspect.
Counsel assisting Andrew Woods said it was suggested the man had used Ms Gobbo as an alibi.
Mr Ryan said he couldn't recall specifically, but suggested that man may have been using her.
Australian Associated Press
