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First Documented Use of DNA in Criminology

DNA profiling is a method of analysis that allows forensic scientists to identify an individual based on his unique genetic code. Small samples of an individual's DNA are contained within blood, skin cells and other biological materials that might be left at the scene of a crime. Modern forensic DNA techniques were pioneered in the United Kingdom during the 1980s.

Initial Research
- The first indicators of possible forensic applications for DNA analysis came in 1984, when Professor Alec Jeffreys observed noticeable differences between the genetic patterns of three individuals working on a genetics experiment at the University of Leicester. Jeffreys believed that these observable genetic differences (and similarities) could be used to identify people who were related to one another. The technique was put to the test in an immigration case in which it successfully proved the relationship between members of a British family.
The Dawn Ashworth Murder
- In 1986, Leicestershire Police contacted Jeffreys about the possibility of using DNA analysis in a murder investigation. Fifteen-year-old Dawn Ashworth had been raped and murdered in the nearby village of Enderby. Three years previously, another teenager, 15-year-old Linda Mann, had been similarly raped and murdered in the village of Narborough. Police believed the crimes to be the work of the same killer, and had a suspect in custody. They asked Jeffreys to use DNA profiling to determine if the biological evidence left at the crime scenes matched the suspect.
Richard Buckland
- A local 17-year-old, Richard Buckland, admitted to killing Ashworth but denied having killed Mann. Jeffreys analyzed a blood sample from Buckland and compared it to samples taken from the victims' bodies. The results were surprising. Jeffreys was able to prove that the two crimes were the work of the same criminal. However, the genetic evidence did not match Richard Buckland. Buckland thus became the first person to be exonerated of a crime thanks to DNA evidence.
Colin Pitchfork
- Although Buckland's exoneration was a major scientific breakthrough, it left the investigation without a suspect. Jeffreys, working with the police, undertook a mass sampling strategy in which saliva samples were gathered from more than 5,000 local men. Eventually, one of the samples showed a match. Local man Colin Pitchfork confessed to both killings when confronted with the DNA evidence. He was sentenced to life in prison, the first criminal ever to be caught using the forensic analysis of DNA.

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