However, the review made 13 recommendations, four of which relate to psychological profiling, used controversially in the investigation into the stabbing of Ms Nickell in front of her two-year-old son on Wimbledon Common, south London, in 1992.
The role of psychological profiling in the murder investigation and the use of an undercover policewoman who tried to trap Mr Stagg into confessing was heavily criticised by Mr Justice Ognall at the Old Bailey when the trial collapsed.
The review, set up by Sir Paul Condon, the Metropolitan Police Commissioner, said that the use of offender-profiling was justified when all other traditional methods of investigation had been tried.
But it recommended that when psychological opinion is the basis for undertaking undercover operations a second opinion should be sought.
It also said that the trial ruling should not discourage future use of offender-profiling, that further research into such profiling should be carried out, and that a senior officer should act as an independent adviser.
The inquiry is to be reactivated with fresh detectives assigned to supplement a core of officers involved in the original investigation. But officers warned that little fresh evidence had emerged and held out little hope that the new investigation would lead to a breakthrough in the case.
Assistant Commissioner Ian Johnston countered suggestions that the new investigation was merely a 'paper exercise' going through the motions because of the publicity the murder had attracted. He said the review had been carried out in a professional manner.
Commander Tom Williamson, who will lead the investigation, said: 'This is going to be a bit like looking for a needle in a haystack, except in this case the needle may not exist.'Reuse content