In the afternoon of Nov. 24, OPP officers and Det. Const. Andrew Doyle from the Toronto Police Service arrived at the Moosonee, Ont., home of 61-year-old Joseph George Sutherland.

They were there to serve him with a DNA warrant to obtain a blood sample they planned to compare against the DNA from the crime scene of the unsolved 1983  killings of Susan Tice and Erin Gilmour in Toronto.

Typically, police will attempt to surreptitiously collect DNA from a suspect and then match it against the crime scene evidence before executing a DNA warrant to confirm what they already suspect to be true. 

In this case, police had tried but been unable to surreptitiously collect Sutherland’s DNA. In a rare move, they managed to convince a judge that it was reasonable to believe that Sutherland had committed the killings, and that his DNA could help prove it.

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Sutherland is from a family of five brothers. The Fifth Estate has learned that police had already cleared the other four, and the process of elimination led them to Sutherland’s door. He was arrested and has been charged with two counts of first-degree murder.

Police had employed a technique known as investigative genetic genealogy. It involves entering suspect crime scene DNA into public DNA family tree websites to identify if not the suspect themselves then distant relatives from whom police and genealogists can eventually connect back to a suspect.