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Colin Pitchfork (born 1961, Bristol, England) was the first criminal convicted for murder based on DNA fingerprinting evidence and the first to be caught as a result of mass screening. Pitchfork raped and murdered two girls in Narborough, on 21 November 1983, and on 31 July 1986. He was arrested on 19 September 1987, and sentenced to life imprisonment on 22 January 1988 after admitting both murders.
The crimes
On 21 November 1983, 15-year-old Lynda Mann left her home to visit a friend's house. She did not return. The next morning, she was found raped and strangled on a deserted footpath known locally as the Black Pad. Using forensic science techniques available at the time, a semen sample taken from her body was found to belong to a person with type A blood and an enzyme profile that matched only 10 percent of males. With no other leads or evidence, the case was left open.
On 31 July 1986, another 15-year-old girl, Dawn Ashworth, took a shortcut instead of taking the normal route home. Two days later, her body was found in a wooded area near a footpath called Ten Pound Lane. Like Lynda Mann, Ashworth had also been raped and strangled. The modus operandi matched that of the first attack, and semen samples revealed the same blood type.
The prime suspect was a local 17-year-old youth, Richard Buckland, who revealed knowledge of Ashworth's body, and admitted the crime under questioning, but denied the first murder. Alec Jeffreys, of the University of Leicester, had recently developed DNA profiling along with Peter Gill and Dave Werrett of the Forensic Science Service (FSS) and detailed the technique in a 1985 paper.
Gill commented:
I was responsible for developing all of the DNA extraction techniques and demonstrating that it was possible after all to obtain DNA profiles from old stains. The biggest achievement was developing the preferential extraction method to separate sperm from vaginal cells – without this method it would have been difficult to use DNA in rape cases.
Using this technique, Jeffreys compared semen samples from both murders against a blood sample from Buckland which conclusively proved that both girls were killed by the same man, but not the suspect. The police then contacted the FSS to verify Jeffreys' results and decide which direction to take the investigation. Buckland became the first person to have his innocence established by DNA fingerprinting.
Jeffreys later said:
I have no doubt whatsoever that he would have been found guilty had it not been for DNA evidence. That was a remarkable occurrence.
Leicestershire Police and the FSS then undertook a project where 5,000 local men were asked to volunteer blood or saliva samples. This took six months, and no matches were found.
Later, a man named Ian Kelly was heard bragging that he had obtained £200[1] for giving a sample while masquerading as his friend, Colin Pitchfork, who was a local baker. Pitchfork was arrested at his home in the neighbouring village of Littlethorpe and a sample was found to match that of the killer. He was sentenced to life imprisonment and remains in prison today, over 20 years after his arrest.
References
- ^ Sanders, John (2000). Forensic Casebook of Crime. London: True Crime Library/Forum Press, p.229. ISBN 1874358362.
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