A violent sex attacker was caught when police used ground-breaking anti-terrorism powers to covertly recover DNA from a coffee cup he had used at the end of a four-day surveillance operation.
Detectives followed Keith Henderson to a café where they secretly obtained the forensic evidence which linked him to the horrific assault on two teenagers in 2001.
It is believed to be the first time that the legislation has been successfully deployed in a cold case review and police believe it could help revolutionise the way historic crimes are investigated.
Henderson, who was jailed for 12 and a half years in 2012, believed he had got away the attacks in which he knocked a 16-year-old boy unconscious before forcing his girlfriend to perform a sex act at gunpoint on a river path in Salisbury, Wiltshire.
The victims were left deeply traumatised by the assaults whilst Henderson, 59, evaded a major police manhunt. The full details of the case have only just emerged.
Scene of crimes investigators had painstakingly recovered a DNA profile from a single sperm head. More than 1,500 people were questioned in connection with the inquiry which was later featured on Crimewatch but the attacker was never found.
Chief Inspector Sean Memory of Wiltshire Police re-opened the case in 2007 and traced the DNA profile to Henderson’s family through the national database. During the surveillance operation he was followed to a coffee shop where the cup he had been using was seized by officers and swabbed.
The forensic material could then be used to justify the taking of another sample under the 2008 Counter Terrorism Act which was used as evidence in the successful prosecution.
DCI Memory, who last month received the Excellence in Investigation Award from The Investigator magazine for Best Cold Case, along with a colleague for their work on the inquiry, said the process could become a vital tool in the future.
“Once we had that [the coffee cup swab] we knew it was definitely him and knew it was not some other relative. It left me reassured that we had the right person.
“We only use the covert DNA purely for intelligence. Once we had him we could obtain another DNA profile to use as evidence.
“He never knew we were on to him and had been walking around a free man for 10 years. When we caught him you could see the amazement that we had caught up with him,” he said.
Henderson, who was living in Preston at the time of his arrest was found guilty of assault, possession of an imitation firearm, two counts of unlawful imprisonment and indecent assault at Salisbury Crown Court. He was placed on the sex offenders register for life.