Murder of Shirley Duguay

In 1994, Shirley Duguay of Prince Edward Island, Canada went missing and was later found dead in a shallow grave. Among the most compelling pieces of evidence in the case was a leather jacket covered in Duguay's blood and over two dozen white feline hairs.

Royal Canadian Mounted Police investigators recalled that during a previous interview with the estranged husband, Douglas Beamish, that he had a white cat of which he named Snowball. The detectives confiscated the cat and drew blood in which they intended to use DNA fingerprinting to compare it to the DNA found in the white hairs from the jacket, but they found that no one in the world had done this before.

After contacting the Laboratory of Genomic Diversity, a laboratory specializing not in forensics, but in the study of genetic diseases, detectives and scientists were able to develop a method in which to test the feline DNA. The test included a fail-safe method of randomly testing 20 other cats from the isolated Prince Edward Island, in order to establish the degree of genetic diversity among cats in the area, to rule out the possibility that the hairs found in the jacket came from a close relative of Snowball, or if all the cats on the island had a common ancestor, rendering the DNA test useless.

The tests revealed that the hairs did come from the cat; Beamish was subsequently convicted for the murder of his wife.

The forensic science of testing cat and dog hairs has been firmly established and studied, but it was an unknown science until the Duguay case.