Detective nabs killer John Cooper after decades of cold cases

In Wales, in 1985, siblings Richard and Helen Thomas were found murdered in their farmhouse. This case remained unsolved for two decades. Four years later, the bodies of Peter and Gwenda Dixon were discovered along the Pembrokeshire coastal path. John Cooper, a local man, was later identified as the killer but evaded justice for many years. It was not until 2011 that he was finally brought to justice for these heinous crimes. This breakthrough was largely due to advancements in DNA testing and evidence linking Cooper to the crime scenes. Detective Superintendent Steve Wilkins led the review of these cold cases starting in 2006. He utilized previous police sketches and modern forensic methods to build a compelling case against Cooper. The evidence included blood from one of the victims found in the hem of Cooper's shorts, which had been altered to hide the stain. Additionally, old footage from the game show Bullseye was instrumental in establishing Cooper's likeness to a police sketch made following the Dixons’ murders. Throughout the series 'The Pembrokeshire Murders', viewers witness Wilkins meticulously assembling this evidence, showcasing Cooper's efforts to mislead the police. For instance, Cooper claimed the police sketch created in 1989 did not resemble him, but the show reveals that the footage from Bullseye proved otherwise. This visual corroboration played a crucial role in highlighting Cooper's guilt and establishing the timeline of the murders. The court proceedings surrounding Cooper's trial were gripping, as the jury deliberated and ultimately found him guilty. Viewers reported that these segments were