Rachel Nickell: Murder on the Common examines the circumstances surrounding the murder of the 23-year-old mum.
But why was she killed and how? And where is her attacker now?
Here’s everything you need to know about the devastating crime.
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Who was Rachel Nickell and when did she die?
Rachel Jane Nickell was a 23-year-old mum-of-one who died on July 15, 1992.
Robert Napper murdered her when she was walking with her two-year-old son on Wimbledon Common.
At the time of her death, she was living near Wimbledon Common with partner André Hanscombe and their son, Alexander Louis.
How did Rachel Nickell die?
Napper stabbed Rachel to death; he attacked her while she passed through a secluded area of the common.
He killed her by repeatedly stabbing and slashing her with a knife, then sexually assaulted her, before fleeing the scene.
Napper did not harm Alexander, but the boy witnessed his mother’s murder.
A passer-by found him clinging to his mother’s body, repeating the words, “Wake up, Mummy”.
Read more: Son of Rachel Nickell recalls witnessing her murder as a toddler
Why was Colin Stagg wrongly accused of her murder?
Police launched a lengthy investigation to find the perpetrator.
As a result of public outrage, the Metropolitan Police were under pressure to solve the case.
Police questioned 32 men in connection with the killing, and the investigation quickly targeted Colin Stagg.
Stagg often walked his dog on the Common at that time, and lived nearby in Roehampton.
As there was no forensic evidence linking him to the scene, the police asked criminal psychologist Paul Britton to create an offender profile of the killer.
The police then decided that the profile ‘fit’ Stagg.
They subsequently asked the psychologist to assist with designing a covert operation, code-named Operation Ezdell, to see whether he would eliminate or implicate himself.
The media and trial judge later criticised the operation, calling it a “honeytrap”.
Operation Ezdell
An undercover policewoman from the Metropolitan Police Special Operations Group contacted Colin Stagg.
She posed as a friend of a woman with whom he used to be in contact via a Lonely Hearts’ column.
Over five months, she attempted to obtain information from him by feigning a romantic interest.
During a meeting in Hyde Park, they spoke about Rachel’s homicide but he later claimed that he had only played along with the topic because he wanted to pursue the romance.
The undercover female police officer won his confidence and drew out violent fantasies from him but he did not admit to the killing.
Police subsequently charged Colin Stagg with the murder in a grave miscarriage of justice.
A judge eventually acquitted him and the case went cold – but not before Stagg spent 13 months in prison on remand.
The police force reopened the case in 2002 when more advanced forensic techniques were available.
Colin Stagg trial
When the case reached the Old Bailey, Mr Justice Ognall ruled that the police had shown “excessive zeal” and had tried to incriminate their suspect by using “deceptive conduct of the grossest kind”.
He excluded the entrapment evidence and the prosecution withdrew its case.
The judge acquitted Colin in September 1994 when he threw the case out of court.
Colin is reportedly working at a Tesco store now, years after picking up a £700,000 payout for what police put him through.
He also received a public apology from the Metropolitan Police.
How was Robert Napper caught?
Scotland Yard opened a cold case investigation into Rachel’s murder in 2002.
The cold case review team used refined DNA techniques only recently made available.
A small team of officers examined the possibility that the case was linked to other crimes, as well as looking into witness statements and potential suspects.
Officers compared the injuries suffered by Rachel Nickell with other attacks and consulted forensic scientists about improvements in DNA matching.
Police eventually identified Robert Napper and charged him in November 2007.
He was subsequently convicted in 2008.
On December 18 of that year, he pleaded guilty to Rachel’s manslaughter on the grounds of diminished responsibility.
He was already detained at Broadmoor High Security Hospital in Berkshire for a 1993 double murder.
He had been convicted of the murder of Samantha Bisset and her four-year-old daughter Jazmine in November 1993, 16 months after Rachel’s homicide.
Where is Robert Napper now?
Robert Napper was already in prison for double murder when he was convicted of killing Rachel.
The judge ordered that he be detained at Broadmoor High Security Hospital in Berkshire indefinitely.
Mr Justice Griffith Williams said that Robert Napper would be detained indefinitely at Broadmoor because he was “a very dangerous man”.
It is highly unlikely that the convicted murderer and rapist will ever be released.
Napper, now 55, is a paranoid schizophrenic with Asperger syndrome.
Rachel Nickell: Murder on the Common airs on Thursday May 13 2021 at 11.05pm.
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