The events leading to the first forensic DNA case began in 1983. Lynda Mann was only 15 years old when, returning home from babysitting one evening in the Leicestershire village of Narborough, she was raped and murdered as she took a shortcut along a footpath known by villagers as the Black Pad. It was a path that would be unlikely to be known by anyone who wasn’t local, suggesting the killer was someone from the area.
At the time, the biological side of forensic science was still in its infancy, though there were a handful of tests that could help narrow things down in terms of identifying the perpetrator. Investigators could determine from a semen sample that he was blood group A, which is the case for about 40% of the English population. Having established his blood group, they were able to tell that he was a “secretor,” which is true for about 70% of the population. Phosphoglucomutase (PGM) enzyme testing was also carried out. PGM is an enzyme that both men and women carry, and it comes in a number of different forms; hence, determining which type the perpetrator had could also help narrow things down. The perpetrator was found to be type PGM1+, alongside around 40% of people with European ancestry living in England.
As this combination of factors would be found in around 10% of all men, it was clearly not enough to identify the killer, though it would prove to be useful information a few years later. But for the time being, despite a huge police investigation, including door-to-door inquiries in Narborough and the nearby villages of Enderby and Littlethorpe, the trail eventually went cold.
Then, in 1986, another young girl, Dawn Ashworth, was also raped and murdered just off another footpath, Ten Pound Lane, this time in Enderby, very close to Narborough. As in Lynda’s case, the killer’s modus operandi pointed to someone with local knowledge of the area: both the crimes took place in a part of each village that only locals were likely to know about. The similarities in both cases led the police to link the two crimes. There was a serial killer on the loose.
Then came the first twist in the story, and with it, the first time that DNA “fingerprinting” would be used in a forensic case. Richard Buckland, a kitchen porter, aged 17 at the time and with learning difficulties, had been seen in the area on a motorbike, similar to the one that had been seen in the area when Dawn went missing. He also seemed to know, even before the police did, where Dawn might be found. The police brought him in and, under questioning, Richard confessed to Dawn’s murder, but he staunchly protested his innocence when it came to the second murder: He had not killed Lynda.
With Richard in custody, the police were in a quandary. They were pretty convinced they had their suspect for both cases, but they needed new evidence to break the deadlock and also connect Richard to Lynda’s murder. The detective chief superintendent of the Leicestershire Police at the time, David Baker, had read an article in the local newspaper, the Leicester Mercury, about the work of [geneticist and DNA “fingerprinting” pioneer] Alec Jeffreys in the Sarbah case [of matching a mother and son’s DNA]. David had a brainwave.
The police are always looking for new ways to help solve cases, and he recognized that this new technique could be used forensically: DNA fingerprinting could take this broad biological categorization of the perpetrator from being from a group of about 10% of the population, right down to “a group of one.” And if it could do that, it would confirm whether Richard Buckland had killed both girls, and he would go to jail for his crimes.
In the meantime, Alec and his team were fine-tuning the DNA fingerprinting process. While the patterns of blobs and lines generated in the first version of DNA fingerprinting were ideal for telling individuals apart from one another, they were extremely complicated and difficult to explain in court. Alec’s team had been homing in on just some of these genetic stutters to understand more about them. They had been finding more and more of them across the genome, each following the same pattern — a DNA “word” repeated over and over again many times. It wasn’t the same word as before, however, but lots of different words, each of them tandemly repeated over and over again, and some were highly variable. There tends to be a standard range of repeats that you find in a population — say, between 10 and 27. So far from seeing only three possible combinations, the number of possible combinations was in the many hundreds for one marker alone. The team homed in on markers with considerable variation in the number of repeats an individual might have, making them perfect candidates for developing a more convenient test for casework.
Concentrating on these markers, fine-tuning and polishing the technique, was starting to give what the forensic community, and courts, would want: something that was quick to carry out, easy to interpret (important when explaining things to a jury) but still highly specific in terms of telling individuals apart. It became known as DNA profiling. Alongside this, Alec had published a paper showing that DNA could be extracted not only from bloodstains up to four years old, but also from semen stains.
In another breakthrough, it was now possible to separate sperm cells from vaginal cells and extract DNA from them; hence, DNA fingerprinting could be used to identify the perpetrator in a rape case. Each incremental scientific discovery was slowly leading towards the much-needed breakthrough in the hunt for Dawn and Lynda’s killer.
Just as there was progress on the scientific front, so there was in the police investigation. Like Alec, David Baker could see the potential of linking DNA with forensics, and he was about to give Alec his first case. Between them, they would make history not once, but twice.
DNA fingerprinting could take this broad biological categorization of the perpetrator from being from a group of about 10% of the population, right down to ‘a group of one.’
David’s request was simple. Convinced that there would be a DNA match, he asked Alec if he would run a DNA fingerprinting test on Richard Buckland and then on the samples taken from Lynda. A DNA match linking Richard to Lynda would provide the evidence linking him to her murder as well — both cases would be solved in one fell swoop.
Alec agreed to run the test, and samples from Lynda and Richard Buckland were transferred to his lab just weeks later. This was to be his first ever forensic case and Alec was fully aware of the importance of what he was doing. Within a few days, he knew the DNA testing had worked, and he had his results. It was time to ring David with the news — both good and bad.
The good news was that the DNA analysis had worked, but the bad news was that Richard Buckland’s DNA had not been found with Lynda’s. Lynda’s killer and Richard had completely different DNA fingerprints: The police had identified the wrong suspect for that murder. David then asked Alec to repeat the process with samples from Dawn. Again, the news was both good and bad: The DNA testing was successful, but it showed that, despite Richard’s confession, he hadn’t killed Dawn either. The young lad in custody was completely innocent of the crimes he was thought to have committed. On November 21, 1986, three years to the day since Lynda had been murdered, Richard Buckland was duly released. Thus the first time that DNA fingerprinting was used in a criminal case, rather than establishing the suspect’s guilt, as anticipated, it proved their innocence and exonerated them of a crime. Without it, Richard would have been wrongly imprisoned for a double murder, almost certainly spending decades in prison for crimes he hadn’t committed.*
And while Richard Buckland was the first, he certainly hasn’t been the last in all the years since then. The Innocence Project states that, in the United States, at the time of writing, 203 people have been proved to be wrongly convicted on the basis of DNA evidence, including several individuals on death row. Statistics like these help underline the profound implications of the technology pioneered by Alec and his team.
* Author’s Note: DNA forensic evidence would later be used again to help identify Lynda and Dawn’s killer, Colin Pitchfork.
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