Rachel Nickell: Six mistakes in hunt for serial killer

The failure to heed the warning of Robert Napper's own mother was only the first in a catalogue of errors which left a loner free to stalk, rape and kill with rare brutality

In November 1989, Pauline Lasham called the Metropolitan Police and told them her son had confessed to a rape two months earlier on Plumstead Common, south-east London. She was right. Her son, Robert Napper, had raped a woman, the first of an estimated 106 sexual assaults he would commit. But crucially, his mother had got one bit of information wrong. The attack was not on Plumstead Common, but in a house near by.

Lacking this piece of information, the police found no record of the crime and did not act upon the tip-off. Three years later, in 1992, Rachel Nickell was murdered. The police's failure to act on his mother's warning in 1989 was the first of six chances they had to arrest Napper. But they missed every one. So Napper was still free when he raped and killed Samantha Bissett, 27, and her four-year-old daughter Jazmine in November 1993.

Robert Clive Napper was born in February 1966 in a maternity hospital in Erith, south-east London, to Brian Napper, a driving instructor, and his wife Pauline. His childhood was marred by violence between his parents and he was sexually abused by a family friend when he was 10. As a teenager, Napper was a reticent, obsessively tidy, lonely boy who bullied his brother and spied on his sister as she undressed.

After school he pursued a series of manual jobs, leaving home aged 21 to live in a bedsit in Plumstead. His workmates considered him dull and boring: he turned up on time and did not speak much. But undetected by his colleagues and later, the police, his sexual deviancy became ever more extreme. It started with flashing and voyeurism, then it escalated into rape and finally into murder.

Before he killed Ms Nickell, Napper was suspected of four rapes, and he has since been convicted of three of them. Those rapes were part of a series of 106 sexual assaults known as the Green Chain rapes, in south London in the early 1990s near where he lived. While Napper has admitted his involvement in four of them (one never got to trial), it is suspected, although has never been proved, that he committed all of them.

Apart from his mother's suspicions, which were never acted on, there were five other occasions when police could have apprehended Napper. The first came in August 1992, a year before the Bissett killings and a month after Rachel Nickell's when an E-fit of the Green Chain rapist was issued and a neighbour and work colleague alerted the police to Napper. Officers asked him to visit to a police station on 2 September 1992 and give a DNA sample, but he never turned up. The following day, he was again identified as the man in the E-fit by a caller who identified him as "Bob Napper". Again police visited and asked him to attend a police station to give a sample. An appointment was scheduled for 8 September 1992, but again he failed to turn up.

Despite his unwillingness to provide the police with DNA, knowing it would match samples found on the three rape victims, Napper was then ruled out of the rape inquiry simply because he was 6ft 2in and police believed the man they were looking for was 5ft 9in.

Three days later he was arrested for possession of a firearm and sentenced to two months in prison. In April 1993, a pistol with his fingerprints was found on Winns Common, south London, yet police did not pursue him for this. Seven months later, he murdered Samantha and Jazmine Bissett. Commander Simon Foy, of the Metropolitan Police, admitted that police errors had contributed to the death of the mother and her daughter. "If any of these opportunities had been taken, it is probable that he would have been in custody and would not have murdered Samantha and Jazmine," he said. "We have been absolutely honest about this to Samantha and Jazmine's family and we have told them that we deeply regret that this happened and have apologised to them."

But despite the same sickening brutality in the murders of the Bissetts and Ms Nickell, officers did not see a link and continued with the wrongful prosecution of Colin Stagg for Ms Nickell's murder. Mr Stagg had been charged in August 1993, two weeks before Samantha and Jazmine Bissett were killed, and went on trial the following year. But he was acquitted in September 1994 after the judge, Mr Justice Ognall, condemned the police tactics used to arrest and prosecute him.

These included the honeytrap set up by the Metropolitan Police in which an undercover officer, using the pseudonym Lizzie James, contacted Mr Stagg, who was been awarded compensation of £735,000 this summer, and encouraged him to fantasise about sex and violence. The judge threw out the case saying that the police were guilty of "deceptive conduct of the grossest kind". Now the police were back to square one. It was only a chance misprint in a London A to Z which threw the light of the Rachel Nickell investigation on Napper.

He had been charged with the Bissett murders in May 1994 after his fingerprints were found at the scene. After searching his flat, police found two London A-Zs with certain locations marked in pen by Napper. These correlated to where he had committed the two murders, one rape and two attempted rapes that he would plead guilty to in October 1995.

But one of the markings was on Wimbledon Common, leading officers to suspect that he had perhaps murdered Rachel Nickell too. But the mark was not made by Napper: it was a printing error by the manufacturer.

Nevertheless, officers decided to visit Broadmoor and interview Napper about the Nickell case in December 1995. But he refused to answer questions, telling the police he would discuss or admit his involvement in the case only if they had forensic evidence to link him to the crime. They did not. But in 1999 more sophisticated DNA techniques were developed, and the forensic teams began work on identifying fibres and hair, found on Ms Nickell's body and preserved.

Eventually, in November 2007, a positive DNA match from the body to Napper was found. He was charged with the murder in December and yesterday admitted killing Ms Nickell.

Commander Foy accepted the criticism of his force for allowing Napper to evade justice for so long. He said: "No system is perfect and investigating a murder is not a precise or exact science. These events I have described are a constant reminder that we should never be complacent and always be aware of our unique responsibility to catch and convict those who commit the most serious of all crime. As this case clearly shows, we never gave up in our search for who murdered Rachel."

Napper to be asked about other rapes

As well as the crimes to which he has confessed, Robert Napper is suspected of committing 106 rapes and sexual assaults in the five years before he was caught.

The assaults began in 1989 when he attacked a mother of two in her home in Plumstead. He is thought to have gone on to attack 86 women before he was finally arrested for the murder of mother and daughter Samantha and Jazmine Bissett in January 1994.

By then, he had already killed Rachel Nickell, stabbing her 49 times, raping her and leaving her under a tree on Wimbledon Common in July 1992. He raped again in 1992 and attempted two more rapes, pleading guilty to them in 1995 and to the manslaughters of Ms Bissett and Jazmine.

Officers believe this handful of crimes is the tip of the iceberg. They think Napper was the notorious Green Chain rapist who stalked women in south-east London in the early 1990s. Detectives have identified 106 incidents involving 86 women for which they believe he is responsible.

Police will re-interview Napper in the hope that he will confess to these crimes but he has said before that he will not admit to any crime unless there is forensic evidence to link him to it.

Napper committed his last known crime in November 1993 when he murdered and raped Ms Bissett, 27, stabbing her up to 20 times. After killing Samantha, he went to four-year-old Jazmine's room. She was found smothered in her bed, surrounded by toys, having been sexually assaulted.

The injuries to Ms Bissett and Jazmine were so horrific that a police photographer who recorded images of the crime scene could not work again for months.

Napper pleaded guilty to manslaughter on the grounds of diminished responsibility in October 1995, on the grounds that he suffered from paranoid schizophrenia and Asperger's syndrome. He was sent to Broadmoor and upon his arrival, his psychiatrist, Natalie Pyszora, noted that he was delusional. Napper thought he was a millionaire who had won a Nobel Peace Prize and was featured in Who's Who.

He also claimed he had been awarded medals for fighting in Angola and that an IRA parcel bomb had blown off his fingers, but he had inhaled "sparkle fumes" to make them grow back.