NEWS
05/12/2017 04:45 EDT | Updated 05/15/2017 05:05 EDT

DNA evidence in retrial of accused in Winnipeg teen's death flawed: defence

WINNIPEG — The lawyer for a man accused of killing a teenaged girl in Winnipeg three decades ago told court Thursday the Crown's evidence is deeply, fatally flawed.

In his closing arguments, Saul Simmonds said DNA samples the Crown has used against Mark Edward Grant are so tiny as to be infinitesimal, and could be from one of the many people who had visited the industrial shed where Candace Derksen's frozen body was found with her hands and feet bound with twine in January 1985.

"There were numerous people who entered that shed," Simmonds said, referring to workers at the industrial site, police officers and others.

"We know that certain people touched the twine ... there were dozens of people in this (investigative) process."

Derksen was 13 when she disappeared on her way home from school on Nov. 30, 1984. Her body was found six weeks later.

Grant, a man with a long criminal record, was arrested in 2007 following DNA testing on the twine used to bind Derksen and was convicted in 2011 of second-degree murder.

The conviction was overturned two years later when an appeal court ruled the trial judge erred in not allowing Grant's defence to present evidence that pointed to another possible killer — an unidentified person who tied up a 12-year-old girl in another part of Winnipeg in 1985, while Grant was in custody on another matter.

Between Derksen's death and Grant's initial trial, the DNA samples had deteriorated, court was told earlier this year.

Dr. Amarjit Chahal, the lab director at Molecular World which ran the DNA tests, testified in January that the twine contained DNA from at least two males, and Grant could not be excluded as a contributor. 

Chahal said the lab combined the findings from two different types of DNA tests and concluded that the probability of the main contributor being someone other than Grant was 1 in 50 million.

The defence's expert witness said Chahal did not follow proper procedures and ignored three DNA markers that did not belong to Grant.

Simmonds said Thursday that Chahal's methods were "scientifically corrupt."

"Every scientific principle that is supposed to be followed is rejected by Dr. Chahal," Simmonds told court.

"He makes things up as he goes along."

The questionable DNA, along with the fact a similar attack occurred while Grant was in custody, leaves the Crown with only "wisps of smoke" in terms of evidence, Simmonds said.

"There is virtually no real evidence of any type that Mark Grant has done anything."

The Crown is to make its final submissions Friday.