The mystery surrounding the death of brothel madam Shirley Finn may remain unsolved forever with the Corruption and Crime Commission ruling out investigating her murder.
The 1975 murder of Ms Finn leapt into the spotlight after a retired policeman said he never went public with information linking police to her death, as he feared officers would kill him. The police officer, known as Brian, made a sworn statement to the CCC alleging two detectives were seen drinking with Ms Finn hours before she was murdered in a South Perth car park.
The CCC confirmed this week it had received new information about the murder but commissioner John McKechnie said that while there had been calls for his department to conduct its own investigation into Ms Finn's death, it was a matter for WA police.
He confirmed CCC officers would meet with police this week to discuss whether the current investigation had identified any police misconduct.
"I have written to the commissioner of police asking for any information that may be relevant to our function," Mr McKechnie said in a statement.
"If allegations of police misconduct come to light, then we will assess them in a normal way.
"If allegations of police misconduct do surface, then we will have a further discussion on how we might proceed."
Mr McKechnie said a coronial inquest would be the "most appropriate forum" if fresh information about her death emerged.
But Police Commissioner Karl O'Callaghan said on Monday he doubted a coronial inquest would help solve Ms Finn's murder.
"I think it's getting too late - a coronial inquest would be useful in that it does have extraordinary power to make people respond to questions," he said.
"It may give us some answers but it may not lead to us prosecuting people.
"As time passes, the chance of anyone still being alive or still being fit to testify as a witness or as an accused 40 years later is getting thinner and thinner."
Mr O'Callaghan said the 2002 royal commission into police corruption missed a "golden opportunity" to get to the bottom of WA's most infamous murder.
He told Radio 6PR on Monday morning the 2002 Kennedy Royal Commission by the Gallop government could have helped unravel the mystery of Ms Finn's murder.
Mr O'Callaghan said one of the problems with a royal commission was it had powers to probe matters only after January 1, 1985, so the Finn murder was never investigated.
"They had coercive powers that could have dragged any detective and police officer into the commission and made them respond to questions," he said.
"And we lost a golden opportunity not only to get to the bottom of Shirley Finn's murder but also any police corruption that might have existed at the time."
He said there simply wasn't enough evidence linking police to the murder.
"There are plenty of rumours... there are plenty of things that have been said over the years," Mr O'Callaghan said.
"These rumours get told and retold over beers and they change over time.
"It seems like there was something going on back then but it's very difficult to know what that was."
