Colin Pitchfork was the first convicted murderer and rapist found using DNA typing. He was caught as a result of mass DNA screening. Pitchfork lived in a village in the county of Leicestershire, England. He was working in Hampshires Bakery until he was arrested for the crimes.
In 1983, Lynda Mann was sexually assaulted and brutally murdered. In November 1983, Lynda Mann was returning home from her babysitting and took a short cut route instead of her normal route. She was raped and found on the footpath the next day morning. A semen sample was collected from her body to a person with type A blood. In 1986, another 15-year-old girl Dawn Ashworth was found missing. The next day she was found on the footpath raped. Both of these crimes occurred in similar circumstances and the blood type was the same.
Under pressure, Police obtained a confession from one of the local men but his DNA doesn’t match with the semen samples collected from the crime scene. The mass screening was conducted by collecting the blood samples for DNA testing from all adult men in search of the killer from nearby three villages. More than 4000 men were tested without a match. A woman overheard Pitchfork friend’s conversation in a bar where he stated that he gave blood for DNA testing for Pitchfork. The Police collected a blood samples from him and the DNA matched the sample from both the crime scene.
The method used was Alec Jeffrey’s Restriction Fragment Length Polymorphism (RFLP) analysis to identify the murderer. The DNA typing became a significant tool to identify the murderer to bring him to justice and thereby exonerating the innocent.
Important lessons from the first Forensic DNA profiling are
- Linking of two different crimes by the comparison of the biological evidence.
- Linkage of two different crimes from the mode of operation.
- Biological evidence helped in exonerating the innocent.
- DNA is an investigative tool that brings the offender to justice.
Fundamentals of Forensic DNA Typing-John. M. Butler