JusticeWillBeServed
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Inaccuracy in DNA report called out at Candace Derksen murder retrial
The lab that conducted DNA tests on crime scene evidence and potential suspects in the Candace Derksen case never disclosed an inaccuracy in one of their reports, court heard Thursday.
On day 9 of the retrial into the Winnipeg teen's murder, Curtis Hildebrandt, a former senior scientist and co-founder of Molecular World, was called to testify.
Hildebrandt gave the court detailed explanations about how the seven hairs were cut from slides and the process involved to extract DNA, purify it and copy it to generate DNA profiles.
He told court he tested four DNA samples submitted by police, including one from Grant.
"Once we generate a profile we would run it through the FBI database," Hildebrandt explained. "The goal of that was to see how many 'profiles' matched. Unlike other DNA tests, mitochondrial tests, however, cannot be used to identify an specific individual.
Court later heard Hildebrandt's mitochondrial comparison found all three persons of interest were excluded from any crime scene hair matches, but Grant's "could not be excluded," he said.
"They don't evaluate if you're doing good work," Simmonds said to Hildebrandt, referring to the SCC. "They don't look if you're dealing with degraded DNA or if you're proficient in dealing with degraded DNA."
Hildebrandt agreed.
Simmonds then raised issues with an inaccuracy in Hildebrandt's 2007 report of lab results provided to the police and the courts.
"As a scientist you're supposed to be precise," Simmonds told Hildebrandt, as he pointed out that during DNA testing one of the steps is to analyze the base pairs of DNA strands but 12 were missed, the report indicated.
"Until you entered this courtroom you never told anyone about a problem with respect to the 12 base pairs," Simmonds said.
Hildebrandt denied knowing there was a problem. However, Simmonds suggested Hildebrandt knew this part of a test of the test was missed, and had discussed it with his superior Dr. Chahal after the 2011 trial.