Pet cat’s DNA helps convict owner who killed his friend after an argument

First time genetic code of a cat has been used in a criminal trial in the UK

A killer who stabbed his friend after an argument has been jailed for life after he was identified by the hairs of his own pet cat which were found on the victim’s dismembered body.

The conviction of David Hilder – with the help of eight hairs from Tinker the cat – was the first time that a new DNA database had been used in a homicide case.

The hairs were found on a curtain wrapped around the torso of David Guy after it was discovered on the beach at Southsea, Hampshire, in July last year.

Hampshire police sent the hairs to the United States for initial analysis on the cat’s mitochondrial DNA, the form contained in small structures within cells and passed down the maternal line. The results showed a match with Tinker and none with 493 other American cats, prompting further tests in Britain by scientists from Leicester University’s Department of Genetics. They built a British database using 152 cats from Southsea and other parts of the country.

Using the technique, scientists established there was only a one-in-100 possibility that the hairs were not from Tinker. Further fibre analysis on the curtain that came from Hilder’s home linked him to the killing. He was convicted by a jury of manslaughter last month and jailed for life and will serve a minimum of 12 years in prison.

Dr Jon Wetton, who led the project and has performed similar work on dog DNA, said: “This is the first time cat DNA has been used in a criminal trial in the UK. This could be a real boon for forensic science as the 10 million cats in the UK are unwittingly tagging the clothes and furnishings in more than a quarter of households. Animal DNA offers a way of linking people to places and items through the transfer of their pet’s hairs.”

DNA in cats is less specific than in humans, as the domestication of the animal has meant fewer genetic variants are present. In contrast, certain forms of human DNA found at murder scenes can provide one-in-a-billion matches.

Tinker had a relatively rare genetic make-up shared by a third of cats; the possibilities of accurate matching for the other two-thirds are much more difficult, Dr Wetton said.

Dr Wetton’s team is now working to make the tests more specific for all cats. He told The Independent that the technique was also likely to have wider relevance for specialist police teams investigating wildlife crimes.

The trial at Winchester Crown Court earlier this year heard that Mr Guy and Hilder, 47, had been friends for several years until the quarrel in which Mr Guy was stabbed in the chest and killed. Hilder cut up his friend’s body before riding around on his bike with a large butcher’s box on the front, disposing of the dismembered body parts in the sea. Divers found Mr Guy’s legs and the wrapped up torso was located on the beach, but the rest was never recovered.

Detective Superintendent Dick Pearson, who led the investigation, said: “We were particularly persistent in obtaining as much DNA evidence as possible.”