Annette Mason cold case: Forensic boss says new forensic evidence makes murder 'solvable'.

A retired Queensland forensics boss who worked on an infamous cold case murder has urged police to prioritise the investigation, saying new evidence makes the crime “solvable”.

In November 1989, Toowoomba teenager Annette Mason was killed in a savage attack.

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Nobody has been charged over her murder and a 1991 coronial inquiry returned an open finding.

Inspector John Brand managed forensics before his retirement and continued retesting crime scene material, which he says has resulted in fresh information.

“We have significant information and that information involves forensic evidence and we now have additional forensic evidence that I believe will assist in solving this terrible murder,” he said.

Mr Brand said finding Ms Mason's killer should be made a bigger priority.

"I personally think that it needs to be given to a dedicated team of detectives, people who have the ability and commitment to solve this," he said.

"The significant evidence available since that inquest and some of it in very recent times, I think would greatly assist in bringing this terrible crime to a successful conclusion."

Queensland Police declined to be interviewed, but in a statement said the investigation remained open and urged anyone with new information to contact Crime Stoppers.

A reward of $250,000 has been set for new information.

The Mason family feel they have been denied justice and are urging the Queensland Government to hold a fresh coronial inquest.

Ms Mason's sister Linda is leading that campaign and said her family deserves answers.

"It's like a living hell," she told 7.30.

"You're just stuck in limbo."

"This young life has been taken but no one has been charged — no one's found responsible."

Another retired police officer, highly decorated Detective Brian Tighe, who led the investigation for 10 years, continues to be troubled by Ms Mason's murder.

Mr Tighe retired 15 years ago but continues to scour his notes for an additional clue.

"When you take an oath of service, you don't give it back when you retire, you continue to care, because its in your nature," he told 7.30.

"These people are suffering."

"Justice has to be seen to be done — the Masons haven't seen much happening."

Ms Mason, 15 at the time, was murdered after a night out sneaking in to Toowoomba pubs.

It was just her first week out of home and detectives said she never stood a chance against the murderer who beat her to death.

That night she met a number of dangerous men and police say witnesses were intimidated.

"There was a wall of silence, which we don't find unusual," Mr Tighe said.

"But in this case, there appeared to be a big fear factor with almost anyone we spoke to and it was almost as if they were scared of some monster that was out there and it was very hard to even have a conversation with them."

Police documents from the time show a key person of interest was Allan MacQueen — who spent time with Ms Mason on the night she died.

He may have seen it. If not, he was definitely in the area so it'd be good for them to go speak to him.

He told police they parted ways when Ms Mason was denied entry to a nightclub and said he got so drunk he could not remember how he got home that night.

MacQueen was arrested shortly after Ms Mason's murder on an unrelated armed robbery charge and went on to become one of Queensland's most notorious prisoners.

He led a prison crew called the Angry Gang and was convicted of murder over a brutal attack during which a prisoner was beaten to death with weights in a gym.

MacQueen has just been released on parole and the Mason family believe he should be interviewed by police.

"I believe that he knows something or he knows possibly what happened that night," Linda Mason said.

"He may have seen it. If not, he was definitely in the area so it'd be good for them to go speak to him."

A number of other men who attracted police attention over Annette Mason's murder also had violent histories.

Mr Brand believes a small number of people know who killed Ms Mason and said it is time they came forward.

"If these people man up, or woman up, they should ring Crime Stoppers and give full frank and honest information, instead of this nonsense that they have been telling authorities," he said.

"That is the way to solve these things and all over evidence assists the court to come to a decision on the matter."