Thousands of serious criminal cases in Queensland will need to be reviewed after an inquiry found the forensic lab failed to properly test DNA samples for years because of “grave maladministration involving dishonesty”.

Former judge Walter Sofronoff has recommended Forensic and Scientific Services be restructured in his report, published on Tuesday after a four-month public inquiry.

He found lab managers had focused on speed rather than accuracy in DNA testing and “that scourge has invaded” the validation of process and equipment used, time management and resources.

“Serious problems have existed within the laboratory for many years, some of them amounting to grave maladministration involving dishonesty,” Mr Sofronoff’s report says.

Lab’s failures affected criminal cases, trials

The former Court of Appeal president had no doubt the lab’s failures to obtain all the available DNA evidence from crime scene samples had affected criminal cases and court trials.

“In most cases that will have reduced the prospects of conviction by a failure to obtain evidence which could support a complaint,” the report says.

“It is possible, but unlikely that the failures could have resulted in a wrong conviction.”

Mr Sofronoff said “thousands of cases” should be reviewed, to see if crime scene samples need to be retested for DNA, potentially by a panel including a scientist, a police officer, a prosecutor and a lawyer.

Blame laid on former manager

The report largely blames the failures on forensic services manager Cathie Allen, who has been in the role since 2008 without adequate oversight.

Over time she distorted the aims of the lab and placed obstacles in the way of scientists trying to do their work, it says.

Ms Allen tried to cover up mounting problems with superiors, lab staff and police using a “deliberately crafted series of lies and misleading dodges”, the report says.

“This state of affairs has been caused by both the structure of her role within FSS and her personal performance of it,” it said.

“As a result, the department leadership was not equipped to grapple with the real problem: a malignancy in the scientific management of FSS.”

Mr Sofronoff recommends the lab be restructured with an independent head scientist in charge with a focus on scientific integrity and serving the criminal justice system.

A podcast series about the killing of Shandee Blackburn [centre] nine years ago led to the inquiry into Queensland’s forensic laboratory. Photo: Supplied

But she said Ms Allen deliberately misleading and lying to cabinet ministers “was a very serious finding”.

“I always believe that you should be able to get full and frank advice, but what we’re seeing here is someone, according to the report, who deliberately lied,” the premier said.

“I won’t cop that from anyone,”

Ms Palaszczuk ordered the inquiry after potential problems at the lab were brought to light in The Australian‘s podcast series about the killing of Shandee Blackburn nine years ago.

The 23-year-old was stabbed more than 20 times on her way home from work in Mackay with her former boyfriend John Perros charged with her murder but acquitted in 2017.

-AAP