During the mid-1980s, train stations were a place of fear after three horrific murders in and around London, including Brookmans Park.
Known as The Railway Murders, the first killing took place on December 29, 1985, when 19-year-old Alison Day was raped, strangled and dumped in a river near Hackney Wick station in London.
The shocking murder was followed by a second on April 17, 1986, this time close to West Horsley station in Surrey. As well as rape and strangulation, 15-year-old Dutch schoolgirl Maartje Tamboezer had been hit with a rock and an attempt had been made to set her body on fire.
Police had linked the two deaths and a string of rapes in 1982 and 1984, but this was not enough to save the final victim, Anne Lock.
The 29-year-old was entering an exciting time in her life, having just married and returned from her honeymoon in the Seychelles.
She worked as a secretary at London Weekend Television, and was called to work on May 18, 1986, leaving her bicycle at Brookmans Park station before catching a train to the capital.
She left work at 8.30pm, called her grandmother to say she was coming home, and then caught a commuter train from London King's Cross at 9.45pm.
Anne was supposed to arrive at Brookmans Park around 11pm, but when she failed to return home, her husband Lawrence rushed to the station where she was nowhere to be seen.
Earlier in the day, her bike had been hidden by the murderers, and when she arrived, she was grabbed and led down the railway tracks to a nearby field.
Here, she was strangled to death and an attempt was made to set her body on fire, much like the second victim Maartje.
Miscommunication between Hertfordshire and the Met Police meant her body wasn’t found for nine weeks. By that time, it was badly decomposed and any evidence as to who had killed Anne had been destroyed.
By this time, police had already started to close in on a suspect, former railway carpenter John Duffy.
He had already been charged with the rape of his estranged wife and he had knowledge of the railway, but evidence truly began to mount against him when a rare type of string called somyarn was found in his parents' house, a string which had been used in a tourniquet found at the scene of the first two murders.
On November 26, 1986, Duffy was arrested after following a woman in a secluded park. He was found with evidence linking him to the murder of Maartje and other rape victims.
He was then charged with the murders of the 15-year-old, Alison Day and Anne Lock, and stood trial in February 1988, where he was convicted of two murders and four rapes and sentenced to 30 years in prison – which was later extended to life.
Duffy was, however, acquitted of raping and killing Anne. The mix-up and nine-week search for her body meant forensics could not be used to link him to the murder.
“Due to a major error in planning the search, there was a breakdown in communication between the Hertfordshire police and the Metropolitan Police,” said crime correspondent Jeff Edwards in the Channel 5 series, The Railway Killers.
“Both thought each other was going to cover this 200m section of embankment and it didn't get searched.”
Although Duffy was now behind bars, the case was far from over, and in 1998, he began to talk to police.
During interviews with Les Bolland, he admitted to murdering Anne Lock, but he could not be re-tried due to double jeopardy, which prevents an accused person from being tried again on the same or similar charges following an acquittal.
The time it took to find Anne’s body is a deep regret for detective Paul Dockley, who worked on the case.
“I was pretty devastated. I understood how the judicial system worked, I knew that because of double jeopardy, we couldn't ever charge John Duffy with the murder of Anne Lock ever again,” he said.
Duffy also admitted that David Mulcahy had committed the murders too, and the police finally had the second person they long-suspected had been involved.
Mulcahy would be convicted of three counts of murder, seven counts of rape and was given three life sentences, providing some closure for Anne’s friends and family after Duffy’s acquittal.
“That was difficult to deal with, because our Anne hadn't got any justice, it felt like,” said her best friend, Lesley Campion.
“Having to then deal with that as well on top of losing her, and then the fact that it's just open-ended was very difficult.”
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