A retired police officer who investigated the 1989 murder of Annette Mason says he has no doubt person of interest Alan McQueen was responsible.
Brian Tighe was testifying at the inquest into the death of the 15-year-old who was bludgeoned to death in a house she shared with friends in Toowoomba in November 1989.
Asked by the Mason family's lawyer Clem Van Der Weegen on Thursday whether he believed McQueen was the main suspect, Mr Tighe replied: "Not a doubt in my mind about that."
Annette's body was discovered in her bed with the cause of her death found to be blunt force trauma to the head inflicted with a piece of timber found in the laundry.
Mr Tighe said he was told McQueen had committed the murder by hitting Annette Mason over the head.
"The plank broke the first time and he got another one," he added.
McQueen - who is behind bars for unrelated crimes - has previously been named as a person of interest in Annette's death, but no one has been charged.
Mr Tighe took over the murder investigation from Graham Ruge, who also took to the stand on the final day of the inquest.
Mr Ruge said McQueen's mother changed her evidence to police about the time her son came home early on the day Annette's body was found.
But she had been caught out a few times giving false alibis for him so Mr Ruge knew they could not always believe what she said, he told the inquest.
Mr Ruge also testified about a covert strategy to try and get information from McQueen and his brother Craig Gill in February 1990.
Listening devices were placed in the watch house where the brothers were being held to see what they might say about Annette's murder.
Mr Ruge spoke to Mr Gill about aspects of the murder in the hope he would go inside and talk to McQueen.
The detective said he was listening live when McQueen said to his brother: "Just stick to the story that mum told us to say."
During questioning over his note-taking and methods, Mr Ruge said it was impossible to take notes of "every little thing" during the investigation.
Asked about taking notes of something important, Mr Ruge said: "It's important in hindsight."
The detective said McQueen wasn't a suspect early in the investigation.
"It was only later when a number of other people start saying that McQueen was responsible for it and the fact that he's looking for a false alibi that you start to think well maybe there was something in it," he said.
The first inquest into Annette's murder in 1991 was closed and subject to "reopening at any stage should further evidence become available".
It was reopened in 2018, but adjourned weeks later and further delayed by COVID-19 and DNA tests in New Zealand.
Reopened again last month, the inquest is now being conducted under changes to state legislation that gives coroners more powers to compel witnesses to give potentially self-incriminating evidence.
Coroner Terry Ryan is expected to hand down his findings later this year.
