WINNIPEG — The integrity of DNA evidence used to link Mark Grant to the 1984 killing of Candace Derksen is under fire at the Winnipeg law courts.
Grant is being re-tried for the 13-year-old’s murder after his 2011 conviction was set aside following a lengthy appeal.
He was arrested in 2007 based largely on DNA evidence.
However on Monday, the testing that produced that evidence was slammed by a defence witness .
Dr. Frederick Bieber, a Harvard professor who specializes in DNA, worked with the FBI on American DNA standards and helped identify victims of the 9/11 attack.
“There are so many problems in this case file that relate to the DNA testing performed that I would consider the results fatally flawed,” he testified.
Bieber told the court he found so many different problems with how Thunder Bay lab Molecular World handled the case file that in his opinion the whole report and its conclusions had been undermined.
“It’s among the most egregious departures from proper lab practice that I think I’ve ever seen,” said Bieber.
READ: Candace Derksen retrial moves to DNA evidence
Molecular World tested rope that was used to bind Derksen’s hands and feet.
- ‘Shock and disbelief’ after Manitoba school trustee’s Indigenous comments
- Canadian man dies during Texas Ironman event. His widow wants answers as to why
- Several baby products have been recalled by Health Canada. Here’s the list
- ‘Sciatica was gone’: hospital performs robot-assisted spinal surgery in Canadian first
One of the major problems, said Bieber, was not using a sample of Derksen’s DNA in the testing.
Another was using a sample of Grant’s DNA that was obtained from clothing in the testing.
Because of a series of lab errors it wasn’t clear if Grant’s DNA was in the sample or not which, according to Bieber, led to “A serious example of confirmation bias, or suspect driven bias, by excluding three different genetic locations that exclude him as being the source of the DNA on the combined DNA extracts of the rope.”
Grant’s Defence lawyers have repeatedly questioned the DNA evidence used in the case throughout the trial, now in its fifth week.
Another expert witness also expressed concern over how the DNA testing was done and how the evidence was gathered at the crime scene.
Under cross examination police officers told the court there were no DNA protocols in 1984 meaning no one wore masks and paper bags were used to cover Derksen’s hands and feet in an effort to preserve evidence.
READ: Candace Derksen’s family preparing for murder trial more than 32 years after her death
Grant’s retrial is not being held in front of a jury, just a judge.
It’s been slated to last more than 30 days.
Comments