A barrister can represent criminals at the same time as acting as a police informer, a Victorian detective has told a royal commission into the Lawyer X scandal.
While being grilled about the force's use of lawyer Nicola Gobbo to inform on her gangland clients, Detective Stuart Bateson revealed he did not believe the two roles were incompatible.
"I think you can do two things," he told counsel assisting the commission, Chris Winneke QC, on Thursday.
"Would this ever happen again? Clearly not. But my view is you can be a human source and a barrister at the same time."
Mr Bateson was being questioned about Ms Gobbo representing an accused murderer in a gangland killing, after helping turn a hitman-turned-informer into a prosecution witness for the same case in 2004.
This prompted Commissioner Margaret McMurdo to ask: "Can you be a human source and a barrister acting for someone, when you've also acted for the key witness against that person?"
"Well that, Your Honour, is, I guess, where I feel it's a bit murky," Mr Bateson replied.
He said Ms Gobbo had told the court she had acted for a witness in the case and the Office of Public Prosecutions, if not the judge, knew.
Mr Winneke put to the detective that everyone, crook or not, was entitled to an independent legal practitioner.
"I'm not sure that we agree on the independent. What I would say is that they have absolute right to seek legal counsel," Mr Bateson said.
He also refused suggestions he withheld vital information about Ms Gobbo's influence in the case at the time.
The detective said he had destroyed evidence, which now appears to have turned up in an electronic cache.
According to the detective, the unsigned and draft statement from the hitman-turned-informer was destroyed after the man altered his statement about whether the murder was planned.
The man's story - which implicated other crooks including prolific gangland killer Carl Williams - changed after his lawyer, Ms Gobbo, labelled it "ridiculous".
But police lawyer Renee Enbom on Thursday revealed a copy of the draft appeared to have turned up in documents emailed to her following Mr Bateson's evidence.
"It appears ... that it might be the electronic version of the printed document that Mr Bateson said in evidence yesterday that he secured and destroyed," Ms Enbom told the commission.
Mr Bateson was questioned for hours about the document.
"If the situation is, Ms Gobbo's involvement is being filtered out of this and defence counsel are not getting the full picture, that is a most unfortunate circumstance for the presentation and for the person who's trying to get to the truth to get through the spin," Chris Winneke QC said.
The officer replied it was a "balancing act" and he had taken necessary steps to protect Mr Gobbo's safety.
Police Chief Commissioner Graham Ashton and his predecessors, Simon Overland and Christine Nixon, are expected to front the inquiry.