Premier Annastacia Palaszczuk has appointed former Court of Appeal president Walter Sofronoff QC to lead the Inquiry into the John Tonge Centre amid concerns the lab failed to crucial forensic evidence.

Police Commissioner Katarina Carroll says detectives are reviewing dozens of sexual assault cases stretching to 2018.

“It’s up to about 50 at this stage that have come back as insufficient DNA for further processing,” she told ABC radio on Wednesday.

“So what we do is go back, but certainly I know we’re still reviewing those numbers, so that wouldn’t be all of them.”

Carroll said detectives would be “extraordinarily thorough” in reviewing individual cases, as the public would expect.

She said it was difficult to say if perpetrators who should be behind bars were walking free due to the lab’s testing failures.

“I’m hoping that’s not the case,” the commissioner said.

“I’m hoping that we’ve all been very, very thorough, but certainly it’s our role, it’s our responsibility to make sure that we’re as thorough as we can be in terms of the testing.”

Potential problems with the lab first came to light as a result of The Australian’s podcast series about the investigation into the brutal slaying of Shandee Blackburn.

The 23-year-old was stabbed more than 20 times on her way home from work in Mackay in February 2013.

Her mother Vicki Blackburn welcomed the inquiry, which she said will be starting point to rectify past failures.

“All those people that have been denied justice, through the balance of the lab will now have they hopefully have their chance at justice,” she told Nine’s Today program.

Shandee Blackburn’s former boyfriend John Peros, a champion amateur boxer, was charged with murder but acquitted in the Supreme Court in 2017.

The coroner in August 2020 found Blackburn died from injuries sustained during an incident involving violence with Peros, who used a bladed instrument.

The coronial inquiry was reopened in February to consider “recent issues raised regarding the forensic evidence and testing of evidence in this case”.

Shandee Blackburn’s mother said she hadn’t given up on justice for her daughter, saying she was hopeful the case would be reopened and DNA evidence retested.

The terms of reference for the Commission of Inquiry will be announced this week, with the Queensland Council of Civil Liberties calling for it to hold public hearings.

“An inquiry such as this largely conducted in private would not command the same public confidence as a fully open and public inquisition into the lab’s processes and apparent significant problems and shortcomings,” council president Michael Cope said in a statement.