Chief medical examiner 'in awe' of DNA error, promises cross-contamination was one-off

Newfoundland and Labrador's chief medical examiner believes he knows how DNA from two homicide cases got cross-contaminated at his office.

Dr. Nash Denic, who took over from Dr. Simon Avis last year, learned of the cross-contamination in September. He said he immediately alerted the Justice Department.

On Dec. 31, 2019, Crown attorneys learned of the error and asked that a first-degree murder trial be postponed while the Royal Newfoundland Constabulary reviewed past homicide cases. The RNC's forensic scientist determined there were no issues with DNA in homicide cases over the last four years.

Denic said it's the first time there has been cross-contamination in the office.

"Neither I nor Dr. Avis has heard about issues with DNA collected on our service in any of these criminal cases they've … investigated over the decades," Denic said Friday.

Denic says he believes the DNA was transferred from a glove to a wooden tool used to scrape underneath fingernails.

The wooden sticks come to the office, which is in the basement of the Health Sciences Centre, pre-packaged, with several sticks included.

"During the autopsy we would be using the tool for collecting DNA from each hand of the deceased individual, and the remaining sticks would stay in the package," Denic explained.

"We believe cross-contamination may have happened when the glove handling one of the bodies and using one of these sticks touched the unused sticks in the same original package."

The DNA, Denic believes, was touched and transferred.

'Case in isolation'

That realization was made after two other possibilities were dismissed.

They quickly ruled out the possibly of the cross-contamination happening at the crime scene, as the two cases were almost six months apart.

Contamination at the forensic laboratory testing the DNA is possible, Denic said, but unlikely.

Denic said he made the call to recommend the RNC independently investigate past cases to ensure public confidence in the office.

"This is a case in isolation, as I said, never heard of in all the years I've been practising with the office."

RNC forensics and property director Kathryn Moyse Rodgers was tasked in October with reviewing the homicide cases from January 2016 to the present.

She found nothing of concern.

It came as a relief to Denic.

"We are still in the awe that this happened," he said, adding the office has changed certain processes to ensure cross-contamination doesn't happen again.

"I think there was no stone left unturned."

The RNC has said it is confident cases officers have worked on will not be jeopardized by the cross-contamination as it was an isolated event.

Justice Minister Andrew Parsons has also expressed his confidence in the safety of current high-stakes prosecutions.

As for the first-degree murder trial for Steve Bragg, Crown Lisa Stead said both prosecutors and the defence must assess the situation before rescheduling the trial.

Bragg has been in custody since December 2017 after being charged with the murder of Victoria Head, 36.

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