Channel 4's gripping new drama Deceit has had true-crime fans glued to their sofas since it got underway earlier this month.
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The four-part series, starring Niamh Algar, Sion Young and Eddie Marsan, tells the true story of one of the UK's most catastrophic police operations which saw an innocent man accused and charged with the murder of Rachel Nickell.
But how did the police catch Rachel's real killer Robert Napper and where is he now? Keep reading to find out…
WATCH: Have you be watching the gripping new drama? Check out the trailer here
Rachel Nickell was assaulted and murdered in broad daylight during a walk on Wimbledon Common with her dog and two-year-old son. Her body was eventually discovered by passers-by, who reportedly found her son repeating the words: "Wake up, Mummy".
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The brazen crime shocked the nation and in a desperate attempt to catch her attacker, the police launched a major investigation that ended up pinning the crime on the wrong man.
In 2002, ten year's after Rachel's murder, Scotland Yard reopened the case, determined to give Rachel's family answers. A breakthrough came in 2006 when advances in DNA testing led to Napper being identified as Rachel's attacker.
Robert Napper eventually confessed to killing Rachel after DNA linked him to the scene
By that point, Napper was already serving time for the murder of Samantha Bisset and her four-year-old daughter Jazmine - which took place just 16 months after Rachel's attack. He had been incarcerated at Broadmoor Hospital due to the fact that he suffered from schizophrenia and Asperger syndrome. Other notorious previous inmates at the high-security facility include Yorkshire Ripper Peter Sutcliffe, Charles Bronson and Ronnie Kray.
Colin Stagg was the man who was wrongly accused of Rachel's murder
After being interviewed by police, Napper confessed to the Wimbledon Common murder and was formally charged in 2007. When the case reached court, he originally pleaded not guilty but changed his plea to guilty on the grounds of diminished responsibility.
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At the time, Colin Stagg, who was the man who had been accused of Rachel's murder and forced to stand trial at the Old Bailey in 1994, received a public apology from the Metropolitan Police. He had previously been given £706,000 compensation after suing the force on the grounds of malicious prosecution and wrongful arrest.
Today, Napper is 55 years old and remains behind bars. It seems unlikely that he will ever be released, as the judge presiding over his case recommended he be detained indefinitely due to the fact he remains "a very dangerous" individual.
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