For the first time, the Edmonton Police Service has used DNA phenotyping in the hopes of identifying a suspect in a violent 2019 sexual assault.
After a lengthy investigation with no witnesses, and as “a last resort,” the EPS enlisted an American DNA technology company that specializes in advanced DNA analysis services. The company used DNA phenotyping to produce a “snapshot” composite sketch of the approximate appearance of the suspect based on DNA.
DNA phenotyping is the process of predicting physical appearance and ancestry from unidentified DNA evidence, the EPS explained. Law enforcement agencies use the company’s Snapshot DNA Phenotyping Service to narrow suspect lists and generate leads in criminal investigations.
The case in question dates back to March 10, 2019, when police said a woman was found yelling for help in the area of 103 Street and 114 Avenue at around 5:45 a.m. A woman in her mid-20s was found seriously injured and wearing only a shirt, according to police.
Police said the woman was walking north on the west side of 101 Street between 2:30 a.m. and 5 a.m. There were a number of people at a nearby bus shelter who were picked up by a bus as she walked by. Police said after the bus left, an unknown man who was at the bus stop followed the woman as she carried on walking.
Police said the man allegedly assaulted the woman, then pulled her into the field near St. Basil and Spruce Avenue schools where he violently sexually assaulted her.
“She was just walking home and this suspect just randomly attacked her. It was a very violent occurrence where she was left in the middle of a field, in the snow, it was -27 C that night,’ said Det. Colleen Maynes with the EPS sexual assault section.
“She sustained quite a few injuries and quite serious injuries.”
Police said when the woman regained consciousness, she made her way to the area of 103 Street and 114 Avenue where a resident found her and called 911.
In April 2019, police put out a plea to the public in hopes of identifying the suspect, whom police described as standing five feet four inches and wearing a black toque, pants and a sweater or hoodie at the time of the incident.
Police said there were no witnesses, CCTV footage, public tips or DNA matches in the case. Because the suspect was wearing heavy winter clothing, police said the woman was only able to provide a limited description of the suspect.
In what police call a “last resort” after exhausting all other investigative avenues, they enlisted the services of Parabon NanoLabs in Virginia.
Using DNA evidence, the company produced trait predictions for the man’s ancestry, eye colour, hair colour, skin colour, freckling and face shape.
By combining these attributes of appearance, a composite sketch was created, showing what the suspect may have looked like at 25 years old with an average body mass index of 22. Police said the default values were used because age and BMI cannot be determined by DNA.
“It is important to note that DNA phenotyping composites are scientific approximations of appearance based on DNA, and are not likely to be exact replicas of appearance,” the EPS said in a news release Tuesday.
“Environmental factors such as smoking, drinking, diet and other non-environmental factors — facial hair, hairstyle, scars, etc. — cannot be predicted by DNA analysis and may cause further variation between the subject’s predicted and actual appearances.”
Police said the suspect may be older, have different body composition and may have facial hair or a different hairstyle than shown in the composite sketch.
“This is essentially a last resort after all other investigative avenues have been exhausted,” said Maynes. “It is by no means an immediate path to accusing a suspect. What it does is potentially give us leads in a cold case, and we can follow up with DNA testing from there.”
Maynes said she was pushed to do the DNA phenotyping because she believed she tried everything else that was available to them.
“It’s not 100 per cent accurate but it at least gives us something to work with to generate leads and tips,” she said. “The public needs to get this person off the street so this offence doesn’t happen again.”
In a statement, Parabon NanoLabs said since May 2018, its snapshot division has helped agencies throughout North America solve 230 violent crime cases.
Use of technology about weighing benefits and risks: justice studies professor
Doug King, a professor of justice studies at Mount Royal University, believes the technology can be a useful tool. However, he added when it comes to the use of any new technology, the benefits of using it have to outweigh any potential risks.
“We see the composite picture and then we automatically then assume it’s an accurate composite picture,” King said.
“By putting a composite together we fix it in people’s minds that this is what the person is supposed to look like. So you have to guard against that because then the issue becomes, ‘I see someone who looks like that — my next door neighbour.’ And it turns out it has nothing to do with that person.”
King said some of the benefits of using the technology include narrowing down a list of suspects in any given crime. Or in this case, building a list of potential suspects. One of the risks comes if the composite isn’t particularly accurate.
“If the composite isn’t all that accurate, you can run into the notion of racial profiling, particularly when the profile is a person of colour,” King said.
In its news release, the EPS said “following consultation with community stakeholders, the EPS is aware of the impact this release may have on a marginalized community.
“Due to the severity of the occurrence, the need to advocate for a victim of a violent sexual assault and in consideration of the public safety interest, investigators believe the release of this image based on DNA evidence is required in order to further the investigation. As always, any leads generated from the release of a composite image would require further investigative steps.”
“It’s great that they reached out, but it still has to meet the standard of the criminal justice system and our relationship with the Canadian Charter of Rights and Freedoms,” King explained. “I respect police officers and I’ll take them at their word, but sometimes they don’t see the issues through the right lens. So we always have to be a little bit skeptical.
“In a court of law, to bring charges, you have to have more than mere suspicion. Right now, if the phenotype leads them to a particular group of individuals, it still relies on more police work. They have to go from suspicion to actual physical evidence.”
EPS spokesperson Cheryl Voordenhout said the technology is also being used with missing persons cases and with helping identify unidentified human remains.
Anyone with information can contact the EPS at 780-423-4567 or #377 from a mobile phone. Anonymous information can be submitted to Crime Stoppers at 1-800-222-8477 or online.