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The true story behind ITV drama Code of a Killer

The police drama is based on a chilling true story

code of a killer
Nicky Morris
TV and film writer
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The ITV police drama Code of a Killer returned to our screens last Monday night, telling the story of how a scientist’s discovery of DNA fingerprinting helped catch the killer of two schoolgirls in Leicestershire - but what is the true story behind the drama?

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Set in the 1980s, the two-part drama stars John Simm and David Threlfall as Sir Alec Jeffreys and DCS David Baker, the scientist and police officer working together to solve the murder of two schoolgirls. Using mass DNA screening, the pioneering pair set out to catch the killer.

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Is it based on a true story?

Like many recent crime dramas that have hit the small screen lately, Code of a Killer is based on a chilling true story.

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The series dramatises the police’s investigation into baker Colin Pitchfork, who raped and murdered 15-year-olds Lynda Mann and Dawn Ashworth in 1883 and 1986 respectively.

john sim 1 in grace© Photo: ITV

John Simm plays Sir Alec Jeffreys

DCS David Baker approached Professor Jeffreys after reading about his scientific discovery in the newspaper, which led to the creation of a DNA profile of the murderer using samples taken from the two girls.

Over 5,500 local men were asked to volunteer blood or saliva samples to be investigated. This took six months, and no matches were found.

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However, in 1987, a woman overheard one of Colin’s colleagues, Ian Kelly, revealing to fellow co-workers that he had been asked to give a blood sample while masquerading as Colin. The killer told Ian that he wanted to avoid harassment from the police for his previous convictions of indecent exposure. The woman who overheard the conversation reported it to the police.

Barbara and Robin Ashworth© Photo: Getty Images

Barbara and Robin Ashworth, parents of 15-year-old Dawn Ashworth

Thanks to DNA profiling technology, police arrested Colin in 1987, making him the first person to be convicted of rape and murder using this pioneering technology.

Where is Colin Pitchfork now?

After being sentenced to a minimum of 30 years for his crimes, Colin’s sentence was reduced on appeal to 28 years in 2009. After numerous parole reviews starting from 2016, Colin was released on 1 September 2021.

The Ministry of Justice said Colin would remain under supervision for the rest of his life. A spokesperson said: "Our heartfelt sympathies remain with the families of Lynda Mann and Dawn Ashworth following the independent Parole Board's decision to release Colin Pitchfork.

"Public safety is our top priority, which is why he is subject to some of the strictest licence conditions ever set and will remain under supervision for the rest of his life."

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