Forensic Cases: The Murder of Leanne Tiernan
In August 2001, a man walking his dog in Lindley Woods, near Otley, in West Yorkshire, found the body of 16-year old Leanne Tiernan, buried in a shallow grave. This was about ten miles from her home in Landseer Mount, Bramley, Leeds. She had been walking home from a Christmas shopping trip with her best friend in November 2000 when she disappeared.
How she was foundShe had a black plastic bag over her head, held in place with a dog collar, with a scarf and cable tie around her neck, and cable ties holding her wrists together. Her murderer had then wrapped her body in green plastic bin liners tied with twine.
In the largest search in West Yorkshire, the police searched around 800 houses and 1500 gardens, outbuildings and sheds on her route from the bus stop to her house, as well as searches of a three-mile stretch of canal, drain shafts and moor land.
Length of time since her deathThe pathologist examining her body said that it had not been there since November. She had been strangled and her body stored at low temperatures in the intervening time.
The Dog Collar, The Twine And The Cable TiesPolice tracked down suppliers of the dog collar and found that a man from Bramley had bought several similar to the one found around Leanne Tiernan’s neck. His name was John Taylor, and he was a poacher who had been seen around the woods where the body was found.
The twine was an unusual kind, used for rabbit netting, and was tracked down to a supplier in Devon, which had only produced one batch. It matched twine found in John Taylor’s home.
Some of the cable ties used on Leanne Tiernan were of a type used almost exclusively by the Royal Mail, the patent company of John Taylor’s employer, Parcel Force. When the police searched John Taylor’s house they found more of the cable ties and one of the dog collars.
DNA examinationPolice searched the woods and recovered around 400 items, including cans and magazines, and forensic scientists compared DNA samples from these, the duvet cover and the bin bags with samples from friends, family, residents on the council estate where Leanne lived, and known sex offenders.
Hairs found in the scarfThe scarf tied around Leanne Tiernan’s neck had a few hairs caught in the knot. Unfortunately, there was not sufficient DNA in the roots for standard DNA profiling. However, the scientists found very small amounts of DNA in the hair shaft and used mitochondrial DNA testing to match it to John Taylor.
First British murder investigation using dog DNA profilingThere were dog hairs on Leanne Tiernan’s body, and scientists in Texas produced a partial dog DNA profile – this was the first time a British murder investigation had used dog DNA profiling. However, John Taylor’s dog had died, so this could not be used in evidence.
The carpet and bloodstains under floorboardsForensic scientists found a strand of pink carpet fibre on her clothes, with specific patterns of dye. Though John Taylor had destroyed the carpet by burning it, police found strands around a nail that matched the fibre on her jumper. Searching under the floorboards, police found bloodstains that the forensic scientists identified as belonging to Leanne Tiernan.
The arrestJohn Taylor was arrested in October 2001, and sentenced to two life sentences in July 2002. In February 2003, he was convicted of two rapes, based on DNA evidence, and given two additional life sentences.
Now find out moreTo find out more about the various forensic principles used in this investigation, read the following:
- How a pathologist might have found that the body had not been there since November in -Estimating the time of death
- How the hairs and fibres on the clothing and carpet would have been analysed in - Hair and fibres in forensics
- The way the bloodstains found under the floorboard were identified in - Bloodstains and tyre tracks
Read about more forensic cases in our casebook category.