DNA allows homicide trial to begin in Sarnia, 28 years after victim was sexually assaulted and murdered in Petrolia

New hope has come about in the form of DNA for an elderly woman who was brutally murdered and sexually assaulted in Petrolia almost three decades ago by a 44 year old man who was only 15 at the time of the incident.

A murder trial that is expected to take 6 weeks has begun in Sarnia and will hinge on a single thumbprint and semen samples found at a crime scene in Petrolia 28 years ago, Lambton Crown attorney Diane Foster told jurors in her opening statements yesterday.

In her opening address, Foster said new investigative techniques prompted a retesting of evidence collected at the home of 70-year-old Velma Thomson, who was killed between Oct. 11 and Oct. 14 in 1983.

"At that time DNA testing wasn’t even on the horizon," Foster told the court.

Genetic fingerprinting was identified in 1984 but didn’t become commercially available to law enforcement until 1987.

The court was told that new genetic-testing technology has determined that semen from the man charged with Thomson’s first-degree murder was present on her slipper and pubic hair.

As the charged person was 15 years of age at the time of the offence, the Youth Criminal Justice Act prohibits the release of his name.

Thomson's body was discovered inside her Kerby Street home in Petrolia on the evening of Oct. 14, 1983, her cause of death determined to be as a result of stab wounds. She had also been sexually assaulted.

She was found face down in a pool of blood with her throat slit.

The fact she was sexually assaulted when killed makes it a first-degree murder case.

Thomson, who had suffered a stroke some time before her death, lived in a tidy bungalow at the end of a cul-de-sac that she had previously used as a hairdressing salon.

The right thumbprint found near the woman’s body belongs to the man charged, Foster said.

When the incident happened, Petrolia police contacted the OPP to assist with the homicide investigation. Despite hundreds of interviews and the seizure of evidence, investigators were unable to determine who was responsible.

The case remained unsolved for nearly 30 years.

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