DNA results were 'unreliable and flawed,' expert at Candace Derksen retrial says

A leading American expert maintained DNA results linking Mark Grant to Candace Derksen's 1984 killing were inaccurate at Grant's retrial Tuesday.

Frederick Bieber, a geneticist and professor at Harvard University, was called by Grant's defence team to analyze the DNA results from a Thunder Bay lab which re-ran tests on crime scene evidence in 2007.

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During cross-examination, the Crown asked Bieber if the defence requested he run any of his own probability calculations to determine if Grant was a match.

"I was asked to review the material and make any recommendations," Bieber said. "And since I felt the data were unreliable and flawed and basically were exclusionary there would be no calculation that's relevant to [this case]."

Candace's body was found frozen and bound with twine in an Elmwood storage shed in 1985, seven weeks after she went missing.

DNA tests from Molecular World linked Grant to crime scene evidence in 2007. He was charged with second-degree murder and found guilty in 2011.

Two years later, a Manitoba Court of Appeal judge granted a retrial after deciding potentially relevant evidence was excluded from Grant's first trial.

Defence experts discussed'generalities' in case

Crown Attorney Michael Himmelman asked Bieber if Grant's defence lawyer Saul Simmonds requestedan "alternative opinion" to the results from the Molecular World lab.

"No, I think he wanted my opinion," Bieber said. "I told him what I would tell you if you had called, that I can't tell you what my opinion will be. It will be the same if the other party in the matter asked for it and you might not like it."

In an effort to challenge Bieber's credibility, the Crown questioned him extensively on the knowledge he had of the case and previous testimony before he came to hisconclusions on theresults.

Himmelman also asked if Bieberconferred with the defence's otherDNA expert, Bruce Budowle, because the pair havepublished research together on at least fiveoccasions, the court heard.

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Bieber said he spoke to Budowleabout generalities in the case, such as scheduling, but they did not discuss details of each other's analysis.

Biebertold the court he reviewed the data from Molecular World and transcripts from the first trial.

However, he denied reading any of the conclusions from the scientists at Molecular World before conducting his own review of the DNA data.

"I would, as a rule, never look for others' opinions to guide me in making my own conclusions," Bieber told the court. "I think it would be introducing the problem I referred to on multiple occasions [Monday] as bias."

Court heard from Bieber thatscientists at Molecular World "deliberately ignored" DNA markers that would have excluded Grant in order to match him to evidence. The lab results were a "textbook example" of suspect bias, he said.

"Well, that's your opinion," Himmelmanresponded Tuesday. "Even experts with resumes as long as yours can sometimes disagree on how to interpret [DNA] mixtures, is that fair to say?"

Bieber agreed.

Crown attacks inconsistency in testimony

The Crown did point out an errorBiebermadein his criticism of the lab file.

On Monday, Bieberfaulted the lab for not re-running tests on Grant's blood sample to obtain a clean DNA profile for comparison.

Bieber arguedthe sample, as it was, was not adequate for comparison and scientists should have tested it again or asked police for a new sample.

However, Himmelman directed Bieber back to the report to show the labdid in fact run a second test on the blood sample.

"This appears to be a second run, does it not?" Himmelman asked.

Bieber agreed.

Himmelman asked the witness whetherhe agreed that he misrepresented Molecular World by suggesting they did not run a second test.

Bieber said he was mistaken in his testimony because he did not have his notes with himbut pointed out a second DNA samplethe lab acquired from Grant was not run a second time.

Himmelman asked Bieber whether he felt the lab "did anything right" in terms of their testing and interpretation.

Bieber said he had "no scientific" concerns with regards to the mitochondrial DNA tests conducted at the lab.

Overall, Bieberdid not waver in his criticism of the lab and said if it was up to him, the report from Molecular World would not have been published.