Snowball

Snowball was an ordinary white cat living on Prince Edward Island, Canada, and he is the reason non-human DNA has a place in criminal courts. In October 1994 a car was found abandoned near Tyne Valley with its licence plates removed and blood spattered inside. It belonged to Shirley Ann Duguay, a 32-year-old mother of five who had not been seen since 3 October. Her body was found in a shallow grave in May 1995; her hands had been tied and she had been strangled.

Close to the grave, RCMP investigators recovered a plastic bag containing a man's leather jacket. The lining was soaked in Duguay's blood — and it also carried white cat hairs. Officers remembered that during an earlier interview Duguay's estranged common-law partner, Douglas Leo Beamish, had a white cat named Snowball. The link seemed obvious. The problem was that nobody in the world had ever tried to match an animal to a crime scene by its DNA, and there was no established method to do it.

The investigators approached the Laboratory of Genomic Diversity, a research group whose ordinary work was genetic disease rather than forensics. Working with the police, the scientists developed a way to profile the feline DNA in the hairs. Crucially, they also built in a control: because Prince Edward Island is a small, isolated population, cats there might all be closely related, which would make any match meaningless. They sampled twenty other island cats to measure how much genetic variation actually existed. The diversity was ample, and the hairs from the jacket matched Snowball specifically.

Beamish was convicted of second-degree murder and sentenced on 19 July 1996 to 18 years to life. He appealed in 1998 and again in 1999 and was refused both times; the appeal judgment, R v Beamish, is where the case is formally recorded. A parole application in 2013 was denied, and he was released to a halfway house in 2025 after 29 years, with conditions barring him from returning to the province.

The case opened a whole field. Pet DNA — cat and dog hairs shed onto clothing, car seats and carpets — is now a routine forensic resource, precisely because animals moult constantly and their owners carry the evidence around without noticing. Snowball himself did nothing but be a cat in a house. The trial that made his name is remembered as the first in which an animal's genetic profile was admitted as evidence against a human defendant.