After 16 years, Britain's most notorious unsolved murder case was finally closed yesterday when Robert Napper, a paranoid schizophrenic with a history of rape and murder, admitted the 1992 killing of Rachel Nickell on Wimbledon Common.
His conviction forced the Metropolitan Police to apologise to Colin Stagg, the man they had wrongly accused of the 23-year-old's murder.
Police officers missed at least six opportunities to apprehend Napper before finally arresting him in 1994 for the murders of Samantha Bissett and her daughter Jazmine in their home in Plumstead, south London, in 1993.
Their first chance was in 1989, three years before Ms Nickell's killing, when Napper's own mother told police her son had committed a rape.
Yesterday Napper, who is already being held at Broadmoor high security psychiatric hospital for the Bissett murders and three sexual assaults, pleaded guilty to manslaughter on the grounds of diminished responsibility.
The judge, Mr Justice Griffiths Williams told him: "You are, on any view, a very dangerous man."
Ms Nickell was killed on 15 July 1992 as she walked through Wimbledon Common with her two-year-old son, Alex. She was stabbed 49 times and sexually assaulted in front of her child.
Initially police believed that Colin Stagg, now 45, had killed the young model and set up a honeytrap to try to get him to confess. He never did but was charged anyway. The case did not go to trial; the judge threw it out and criticised the police for their tactics in trying to get an admission.
Mr Stagg has been compensated with £706,000. Speaking outside the Old Bailey, Assistant Commissioner John Yates said: "In August 1993, he was wrongly accused of Rachel's murder. It is clear that he is completely innocent of any involvement in that case. I today apologise to him for the mistakes that were made in the early 1990s and we also recognise the huge and lasting impact that this has had on his life and on behalf of the Metropolitan Police today I have sent him a full written apology."
Napper's psychiatrist, Natalie Pyszora, told the court yesterday: "His intent was to find a woman for sex and he went to Wimbledon Common with a knife." His state of mind had been "psychotic" and his two mental conditions – paranoid schizophrenia and Asperger's syndrome – "gave him the feeling that he was untouchable".
After Ms Nickell's death, Napper murdered and sexually assaulted Samantha Bissett and her four-year-old daughter Jazmine in Plumstead. He pleaded guilty in 1995 to two counts of manslaughter on grounds of diminished responsibility and also admitted to one rape and two attempted rapes.
He has been in Broadmoor since and yesterday Mr Justice Griffiths Williams sent him back, saying it was "very unlikely" he would be released.
The court heard a victim impact statement from Ms Nickell's parents, Andrew, 68, and Monica, 64, who said the death of their daughter was comparable to being run over by "a very large truck" and said: "We hope the man who committed the crime will spend the rest of his life in prison. That is the sentence he has given us."
That man, Robert Napper, 42, spoke only once to confirm his name and that he wished to plead guilty to manslaughter. His barrister, David Fisher, made a statement on his behalf. Napper had asked him "to say sorry to Rachel Nickell's partner and their son and to other members of her family, particularly her parents and close friends for the dreadful thing that he did. He knows and I know that words cannot mend what he has done, but I hope I will be right in saying that it is better for him to express real sorrow and remorse than for nothing to be said."
During the hearing, Rachel's mother had to be comforted by her husband as details of her daughter's death and her killer were discussed.
Outside court, Mr Nickell said: "Mr Napper has been found guilty of Rachel's murder. That means in total he has murdered two women, one child, raped at least one woman and attempted to rape two others.
"We sincerely hope that whatever the court says, that he will spend the rest of his life in a totally secure environment to protect all other people. A long time ago we came to terms with Rachel's death. Our lives have changed forever but we've learnt to accommodate the changes. We now hope to draw a line and move forward."
Mr Nickell also praised the investigating officers, despite a catalogue of blunders which saw them miss a series of chances to arrest Napper sooner, and the fact that they persisted with a suspect who turned out to be innocent.
Napper's mother said she had disowned her son. "I could not cope with the shame and torment, that I had brought this person into the world."
The greatest loss is your future... The victim impact statement from Rachel Nickell's parents Andrew and Monica
We have been asked to provide an impact statement to try to describe how Rachel's murder has affected us. This is a bit like trying to describe how you felt after being run over by a very large truck. In both cases you come out of a coma months/years later having lived through a period when you were not really conscious of what was going on but you keep on automatically breathing and eating. When you come to you gradually realise what you have lost.
The greatest loss is your future. All the things that any family hopes for and expects are completely smashed. There will be no daughter to talk to in our old age, no grandchildren to love and admire. At a stroke all this has been removed.
The next loss is your anonymity. Your life is trampled on by the media. You are gawked at in supermarkets. You are avoided by so-called friends who think some bad luck will rub off on them. Your son is devastated as he is very close to his sister. He avoids any close relationship because he fears losing someone else. Your mother, in her eighties, cries every day and wishes she had been taken instead.
Your daughter's partner retreats into pain and blame without the guidance and love of your daughter. After a few years he moves abroad and later you are stopped from seeing your only grandson. You become ever more wary of strangers. You reveal nothing because they might be media or have contacts with the media. Copies of your phone bills are obtained and friends abroad ring up to try to discover where your grandson lives.
You fight the Criminal Injuries Compensation Board for recompense for Alex for losing his mother in horrible circumstances and the loss of her love and parenting skills for the 15 years until he is 18. After seven years he is awarded a derisory amount. The Home Secretary tells you that there is no appeal against this award. You deal year after year with the machinery of the Crown and the ever-changing teams of police and specialists. Some of them care deeply but they come and go.
To say one man has destroyed our lives is too strong. But that one man has changed it forever. You learn to accommodate these changes but the pain remains with you every minute of every day. Every day Rachel's name is mentioned, her photograph published or her home videos shown, everything comes flooding back.
We hope the man who committed the crime will spend the rest of his life in prison. That is the sentence he has given us.