Genetics expert slams lab that linked Mark Grant to Candace Derksen's killing

A genetics expert with decades of FBI experience persisted in his criticism of the DNA lab that linked accused killer Mark Grant to Candace Derksen's 1984 killing at Grant's retrial Tuesday.

"If one puts in validation studies and documents the procedure and establishes interpretation criteria I might consider it," Bruce Budowle said of the lab's reports during cross-examination.

"In this case, none of that was put in place."

Budowle was called by the defence team to analyze the DNA results from Molecular World, a Thunder Bay lab which ran tests on key evidence, including the twine Candace's body was found bound with.

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The 13-year-old's body was found frozen and boundwith twine in anElmwoodstorage shed in 1985, seven weeks after she went missing.

Grant was charged with second-degree murder in 2007 andfoundguilty.In 2013, a Manitoba Court of Appeal judge granted a retrial after deciding potentially relevant evidence was excluded from Grant's first trial.

As he first told court Monday, Budowle reiterated thatDNA results were "incorrectly interpreted" and driven by "suspect bias"because scientists disregarded data that would have excluded Grant.

A DNA marker appeared on the twine could not have come from the victim or Grantbut the information was ignored, Budowle said.

"My position is it should be inconclusive. You can't make a decision one way or another for how that can be generated."

He suggested, again, that scientistsmust have referenced Grant's sample before analyzing the results, which he argued would naturally resultin "suspect bias."

On Monday, he said he believes because the lab looked atGrant's sample first, itfound patterns with the results and then disregarded data that didn't align with its hypothesis.

Expertquestioned aboutown bias

Crown Attorney Michael Himmleman suggested Budowle may have been biased in his own analysis of theresults, which were given to him by Grant's defense team.

The Crown asked if Budowle was made aware of the case's backgroundand the allegations against Grant before he came to his conclusions. Budowle said he could not recall when he got that information.

"I often don't want to know that before [looking] at the DNA evidence," he said.

"You can't tell us if you knew the context of this case before coming to your conclusions?" Himmelman asked again.

"No," Budowle responded.

He told the courtit was necessary for him to read the testimonies from scientists at Molecular World to understand how they interpreted the initial results, but that would have happened after his initial review of the documents.

Himmelman asked if Budowle believed in "context bias" and that having knowledge of the case details may have influence on analysis.

Budowle told court contextual bias was similar to suspect bias, which is what he was concerned about in the lab's findings.

Responding to a question from Himmelman, Budowle also said he was not asked by the defenceto look for evidence that would exclude Grant.

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The Crown asked Budowle`s opinion of the technology the lab used, its protective gear and the procedures in place to prevent contamination.

He told the court he had no concerns about the equipment, instruments or protective gear worn they were all acceptable.

But he did say he had concerns with how that technology was used.

"How they used [it] doesn't seem to be generally accepted or recognized," Budowle said.

Grant's defence lawyer, Saul Simmonds, will call his next witness to testify on Tuesday.

Michael Himmelman and Brent Davidson are the acting Crown attorneys. The judge-only retrial is being presided over by Justice Karen Simonsen.