TORONTO â€” Police in a northern Ontario city have turned to an emerging technology to try and solve a 19-year-old homicide.
The slaying of Renee Sweeney has stymied police in Sudbury, Ont., since 1998, when she was repeatedly stabbed behind the counter of the adults-only video store where she worked.
Evidence in the case included multiple DNA samples, fingerprints and three witnesses, but the killer has not been identified to this day.
Now, Sudbury police have turned to DNA phenotyping, an increasingly popular technology among American law enforcement departments, to solve the case.
Phenotyping involves using a DNA profile to extract specific information about a suspect, such as ethnic makeup, face shape and eye colour.
Police have now released a photo of the suspect based on his DNA profile and are hoping it helps crack the case.
For Det. Sgt. David Toffoli, who was lead investigator on the Sweeney slaying for nearly a decade and is now a forensic supervisor with the Sudbury police force, solving the homicide would be a personal victory.
“I’ve been on it for almost two-thirds of my career and it’s definitely stuck with me,” he said in a telephone interview. “A lot of work has gone into it, a lot of hours of policing. And it’s definitely one of those cases that I want to solve before I retire.”
Sweeney, 23, was a student at Sudbury’s Laurentian University at the time of her death.
She was studying music and playing frequent shows with the local symphony orchestra in the evenings, Toffoli said, adding she took the job in “the porn store” because the hours better suited her schedule.
Her death came in the middle of her shift on Jan. 27, 1998, and has been isolated to a 15-minute window.
Toffoli said Sweeney was on the phone to a co-worker across town at 11:15 a.m. and indicated that a customer had entered the store. Two more customers walked in at 11:30 in time to see a single male suspect fleeing the scene.
A minute later, they discovered blood stains that led them to Sweeney’s body lying behind the counter with more than 30 stab wounds.
Toffoli said no one in the busy strip mall where the store was located heard any sounds of a struggle, and witnesses were immediately able to provide enough information for police to produce a sketch, though the resulting image never led anywhere.
Nor did DNA profiles extracted from under Sweeney’s fingernails and from clothing the suspect had abandoned at the scene, he said.
Police investigated for years, comparing about 1,800 people to the DNA results and failing to come up with a match.
The profile also never surfaced in other databases either in Canada or the United States, a source of frustration for officers involved.
“There was a feeling that with the DNA we’d be able to identify the suspect positively,” Toffoli said. “We were hopeful that we’d be able to find him with all the tips we received. Unfortunately, no one’s matched up to that DNA.”
It was just last year that Toffoli said the force decided to explore the relatively new field of phenotyping. While the technology has existed for a while, he said, companies that offer the service have taken longer to become known.
One such firm is Virginia-based Parabon NanoLabs, whose “snapshot” technology is being used in a growing number of U.S. criminal cases.
Most recently, the company said one of its composite images derived from a DNA profile helped identify and convict a North Carolina man who gunned down a couple in their home in 2012.
Last year, a police force in Hallandale Beach, Fla., released a sketch generated through phenotyping of a woman believed to be involved in the deaths of a Canadian couple. The local police chief said at the time that the sketch has the force one lead away from solving the asphyxiation deaths of David Pichosky and Rochelle Wise, of Toronto, who were killed in 2013 at their winter home.
Toffoli expressed much the same sentiment about the Sweeney case, saying the new image generated about a hundred tips within 24 hours of its release Monday.
At $6,000 it’s a costly endeavour, particularly for smaller police forces with limited financial resources, but Toffoli said the composite may be enough to jog someone’s memory.
Past examples have shown that the images generated through phenotyping are often quite accurate when compared against photos of the suspects they help to catch, he said, adding people should pay attention to details.
“They’re not identical, but there’s always a resemblance there,” Toffoli said. “And that’s what we’re hoping for, that people will look at this Parabon composite and just see that resemblance â€” whether it’s the shape of the nose, the chin, the eyes â€” and call that tip into us.”
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Michelle McQuigge, The Canadian Press