Nearly three decades after 80-year-old Thera Dieleman was murdered in her Oxford County home, OPP have released a composite sketch of her killer, created using DNA from the crime scene.
Police released the never-before-seen images at a news conference held Tuesday morning. Crafted by DNA technology company Parabon Nano Labs, one of the sketches depicts the murder suspect as he may have looked at the time of the killing, while the other image shows how he may look today.
"We are not in anyway trying to suggest that this is an identical picture of the killer," said Detective Superintendent Ken Leppert. "We are trying to do the best job we can with the available technology that is out there in the DNA world to stimulate people's memory, people who may have known a certain individual or a person of interest at the time of the offence. Their memories might be ignited by looking at this composite sketch and by us putting it on social media across the world."
The images are said to be "scientific approximations" based on DNA that do not take into account non-genetic factors like facial hair, hairstyle, scars, or lifestyle choices such as smoking, drinking, and diet.
It is the first time OPP have used this type of technology to try to crack an unsolved homicide.
"Other law enforcement in Canada and across the United States have used it. It's my understanding that there has been several success stories in the United States using Parabon technology," said Leppert.
Dieleman was beaten and strangled to death inside her Innerkip-area home on September 16, 1988. The widow put up a fight and potentially injured her attacker, according to police.
Witnesses told police they had seen a red flatbed farm truck with white lettering on the doors, dual rear wheels, and a black headboard protector behind the cab parked in Dieleman's driveway on the day of the murder. Police never located the person or persons who were driving the truck.
A $50,000 reward remains in place for anyone with information leading to the arrest of Dieleman's killer.
"It's very common in any violent crime that their could be witnesses out there that for a number of reasons -- their affiliation to the culprits or for personal safety reasons -- may not have come forward at the time of the occurrence ," said Leppert.
Anyone with information about this case is asked to call the dedicated tip line at 1-844-677-9414 or Crime Stoppers at 1-800-222-8477 (TIPS).
