Queensland DNA debacle: killers ‘getting free pass’
Serious and violent offenders are better off in Queensland because the government’s forensics lab has set a very high threshold for detecting DNA, a leading expert says.
Serious and violent offenders including killers and rapists are better off in Queensland because the government’s forensics laboratory has set a very high threshold for detecting DNA, according to a leading expert.
The health department’s lab has demanded that to progress to DNA profiling, crime scene samples must contain double the number of cells required in NSW.
Podcast series Shandee’s Story reveals samples are being declared as having no DNA as a result of the unusually high threshold levels.
Forensic biologist Dr Kirsty Wright says the threshold means it is highly likely samples with lower levels of DNA would be getting sidelined and not fully tested.
There was “potentially a very large number” of cases where offenders aren’t being identified when they should be, Dr Wright said.
“It’s frightening. It absolutely makes me sick,” she said.
Bruce Morcombe, father of murdered schoolboy Daniel Morcombe, said the state government must investigate. “It’s not good enough, as simple as that,” he said.
“Somebody is not doing their job and it’s alarming. It actually makes me quite upset.”
Scientists, lawyers and victims have been calling for a broad, independent inquiry into systemic failures and errors identified in the lab during the Shandee’s Story series but Premier Annastacia Palaszczuk, Health Minister Yvette D’Ath, Attorney-General Shannon Fentiman and Police Minister Mark Ryan have ignored the calls.
Queensland Health this week refused to answer questions about the forensics laboratory and its DNA thresholds.
Mr Morcombe questioned whether the lab was using a high threshold to reduce its workload.
“Queenslanders deserve to know why. The leadership in that area needs to be quizzed,” he said.
“Give them the opportunity to provide an answer, but at the end of the day, if you’re not doing your job, let’s find someone that’s capable. We need peace of mind for the families. We owe it to the victims. Most importantly, we need the people responsible to be apprehended and jailed.”
The Women’s Legal Service Queensland has also expressed alarm, warning that DNA failures would have a “devastating effect” on investigations.
The Australian last week revealed the lab was failing to detect DNA in rape and sexual assault cases.
“If the conclusions … are correct, WLSQ joins other legal and scientific experts, as well as victims of crime themselves, in calling on the state government to order an independent inquiry into the Queensland government-run forensic laboratory,” spokeswoman Julie Sarkozi said.
Sexual assault survivors represented by the legal service had told of DNA evidence not being collected or being lost or destroyed, she said. “WLSQ knows that police investigations, charges and convictions succeed and fail on the quality of evidence like DNA.”
When government labs across the country receive a crime scene sample, they first try to detect and measure DNA. Typically, the labs set a threshold for the minimum amount of DNA they believe is required to obtain a profile.
If the minimum is not met in the first two testing stages, the labs do not send the samples on for profiling in the final two stages.
Dr Wright has found the Queensland lab requires crime scene samples to have the equivalent of at least 22 cells to be fully tested, otherwise they are deemed to have insufficient DNA.
The threshold is double the 11 cells required in NSW, and almost three times the eight cells that the product manufacturer has used to obtain good quality DNA profiles.
“The threshold used by the DNA lab is astoundingly high. You would have more than enough DNA in that sample if it was below that threshold,” Dr Wright said.
The NSW forensics lab set their threshold lower despite using the same type of equipment as Queensland, she said.
NSW has also reported obtaining DNA profiles from trace samples below the 11-cell threshold.
When they tested eight trace crime scene samples from firearms below this threshold, they got DNA profiles eight times.
Shandee’s Story is investigating the unsolved 2013 murder of Shandee Blackburn as she walked home from work in Mackay on Queensland’s central coast.
In the process, major problems have been discovered in the lab’s handling of crime scene samples, affecting many other cases over a period of years.
Dr Wright said a new DNA profiling kit introduced just before Blackburn’s murder was a lot more sensitive, requiring only very small amounts of genetic material to obtain a profile.
Anyone with information about the murder of Shandee Blackburn can contact Hedley Thomas at shandee@theaustralian.com.au