DNA breakthrough brings murderer to justice
Monica Jepson’s murderer deposited a bizarre clue at the scene of the crime and advances in forensic science eventually identified him from it.
As John Cook, 37, begins a life sentence for the murder seven years ago of the pensioner, the Forensic Science Service explained how he was caught.
Cook had defecated on a fire escape, leading from the victim’s room. The faeces were collected at the time and analysed by scientists.
Dr Jonathan Whitaker said DNA profiling techniques available in 1995 meant that only a limited amount of information could be obtained.
The results were used to eliminate one suspect and proved the material was not Mrs Jepson’s, he said. “In 2001, cutting-edge DNA profiling techniques enabled us to obtain a full DNA profile from the material.
“We were able to ‘clean up’ the DNA we had obtained and get a profile from that and this is the first time a full DNA profile has been obtained from human faeces,” he added.
When the profile was checked against the National DNA Database it matched Cook, whose DNA had been taken as a result of previous convictions for burglary and drugs offences, dating back to his teens.
When his fingerprints were taken they matched those found at the crime scene, Dr Whitaker said. A team of scientists working from the Forensic Science Service’s specialist DNA unit in Birmingham carried out the scientific work using the super-sensitive DNA Low Copy Number technique.
“Many of these crimes were committed before the DNA was even known about and when the police are reviewing unsolved cases they are now looking for material that we can extract a DNA profile from,” he said.
Earlier this year, their forensic evidence jailed for life former army chef Tony Jasinskyj for the murder and rape of 14-year-old Hampshire schoolgirl Marion Crofts in 1981.
The FSS also helped two years ago to convict Richard Lowther for the 1977 murder of Mary Gregson, 39, in West Yorkshire. Dr Whitaker, who gave evidence during Cook’s trial, added: “This case proves how increasingly valuable the National DNA Database is becoming for police investigating crime.
“It also shows how cutting-edge science and traditional detective work hand-in-hand to get results,” Dr Whitaker added.
