The killer of young mother Rachel Nickell was brought to justice yesterday after 16 years of agony for her family and the man wrongly accused of the crime.
Police apologised for their mistakes in not catching sooner Robert Napper (42), who admitted the frenzied knife attack on Ms Nickell (23) in front of her son.
They apologised to relatives of Ms Nickell and Samantha and Jazmine Bissett, also killed by Napper, for missed opportunities to arrest Napper that could have saved their lives.
Police gave a public apology for the first time to Colin Stagg (45), who spent 13 months in prison before being freed by a judge.
Napper, a deluded killer and rapist, could have been caught as far back as 1989 when his mother said he had confessed to a sex attack. But police could not trace the crime and did not interview him or collect his DNA.
He went on to commit at least four more sex attacks before launching a brutal sex attack on Ms Nickell in which she was stabbed 49 times on Wimbledon Common in July 1992.
Her two-year-old son Alex was dragged aside as Napper stabbed the former model, forced her to her knees and subjected her to a violent attack.
Napper walked away leaving local loner Mr Stagg to become the chief suspect, and later be charged with murder following a flawed "honey-trap" laid by police.
Napper's DNA was again not taken when he was questioned about the original rapes a few months later.
In November 1993, Napper killed Ms Bissett (27) and her daughter Jazmine (four) after climbing into their basement flat near his home in Plumstead, south-east London. He mutilated Ms Bissett and suffocated Jazmine after sexual assaults.
Napper was arrested in May 1994 and sent to Broadmoor for their manslaughters a year later.
Meanwhile, Mr Stagg faced a murder trial but the case was thrown out in September 1994 when police were criticised.
It was not until 2004 that new DNA techniques were able to match a speck of DNA found on Ms Nickell's body to Napper.
Napper yesterday pleaded guilty at the Old Bailey to Ms Nickell's manslaughter on the grounds of diminished responsibility and was ordered to be detained in Broadmoor indefinitely.
Victor Temple, prosecuting, said that when Ms Nickell's body was found, Alex was holding on to her by the arm, crying and saying, "Get up, Mummy".
Mr Temple said an officer described the boy as being covered in blood.
Psychiatrist Prof Donald Grubin said Napper had a "toxic" combination of paranoid schizophrenia and Asperger's syndrome. Another doctor, Natalie Pyszora, said there was a danger he would commit more attacks and it was unlikely he would ever be released.
Ms Nickell's partner, Andre Hanscombe, sat in court in front of her parents, Andrew (68) and Monica (64) Nickell.
Mr Nickell told the judge in a statement: "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."
David Fisher, defending, said Napper wished to apologise to them for "the dreadful thing that he did". He said the killer had also asked him to make an apology to Colin Stagg. "At the time of these events, the arrest and the preliminary trial of that man, this defendant was not in a satisfactory mental state to really appreciate what was going on. He is now.
"He realises how dreadful that period of time in Mr Stagg's life must have been," Mr Fisher said.
The judge, Mr Justice Griffith Williams, told Napper: "You are on any view a very dangerous man. You still present a very high risk of sexual homicide."
Ms Nickell had been killed in front of her son. "Now, 16 years or so later, in early adulthood, Alex knows the man who killed his mother has been brought, albeit belatedly, to justice."
The judge added that he hoped the family could now close a "long drawn-out chapter" in their lives.
Outside court, assistant metropolitan commissioner John Yates and a crown prosecution lawyer apologised to Mr Stagg, and Mr Yates admitted police could have done more to catch Napper. "Had more been done, we would have been in a position to have prevented this and other very serious attacks by Napper," he said. - (PA)