On 26 May 2011, John Cooper was jailed for life at Swansea Crown Court, ending his 25 year-long spree of gruesome violence in a quiet corner of Pembrokeshire, Wales. In that time, he had been responsible for two double murders, several sexual assaults and burglaries, and an armed robbery.
His reign of terror began in December 1985 when he killed Richard and Helen Thomas in a bungled robbery at their Milford Haven home. After tying up Helen Thomas he was disturbed by Richard, her brother, returning to the farm. Both were then shot dead before Cooper set Scoveston Manor alight in an effort to destroy evidence. At the time, he lived less than a mile away in a rented property at Jordanston. But he remained undetected despite a 150-man police operation and extensive media appeals.
But he was hardly in hiding - in May 1989, he brazenly appeared on national television on ITV's Bullseye quizshow. Less than a month later on 29 June 1989, Cooper attacked again in broad daylight. Peter and Gwenda Dixon from Witney, near Oxford were enjoying their last holiday walk on a coastal path near Littlehaven when Cooper attacked them. He tied Peter Dixon up, forcing 51-year old Mr Dixon to reveal his bank card details, he then shot them. Peter was shot three times and Gwenda Dixon twice in an execution-style killing. Their bodies were discovered in thick undergrowth six days later - it was clear that Gwenda had been subjected to a sexual assault.
Cooper withdrew just over £300 from Peter Dixon's bank account after the attack. Police released an artist's impression of the suspect, based on witness sightings of a scruffy man acting suspiciously at cashpoints in nearby towns. Many years later, the jury at the murder trial would be asked to compare this drawing to the footage of Cooper on Bullseye. But the similarities were not noted at the time.
Instead, police followed several false leads. One suggestion was that the Dixons had been killed because they had stumbled upon a secret IRA cache on their walk. Despite two Crimewatch appeals for information about the scruffy man and thousands of police interviews, no concrete leads were found. Slowly, the case was wound down, though it was never closed.
Burglaries and an armed robbery
During the same period, Cooper continued to terrorise communities in Pembrokeshire. He carried out a number of burglaries, stashing the stolen goods in local hedges and bushes. In 1996, he threatened five teenagers with a sawn-off shotgun in Milford Haven, only two fields away from Scoveston Park. Disguised by a balaclava, he demanded money, then subjected two of the girls to serious sexual assaults.
That same year, he also committed an armed robbery at an isolated dwelling nearby, occupied by a lone female in Sardis. But his luck was running out. When the woman raised the alarm, Cooper fled the house, discarding his balaclava, gun and gloves in undergrowth on his way home.
Police found the items, and in January 1998, Cooper was jailed for 16 years for burglary and armed robbery. During the burglary investigation, police took a large amount of evidence from his house and surrounding fields. That evidence would be vital for pinning him to the murders and the rapes later on.
Operation Ottawa: Closing the net
In 2006, police reopened the case files on the murders and the Milford Haven attacks. After two years of sifting through thousands of exhibits, witness statements and images, police noticed similarities between all three cases: a similar geographical area, a rural location, the use of a shotgun and the attempts at robbery. John Cooper became their number one suspect, but police still needed evidence.
Fortunately, police had retained enough evidence from the murders that forensic scientists were able to conduct a thorough re-examination. DNA technology and the process of investigating cold cases had advanced a lot since the 1980s, so scientists could test far more evidence than before.
The evidence: Shorts
Scientists examined a pair of shorts that they had found in Cooper's house while gathering evidence for the burglaries trial. Sensitive DNA technology revealed that a minute fleck of blood on the shorts matched Peter Dixon's profile. In addition, there were fibres on the shorts that were identical to those found on Richard Thomas's sock and on the Milford Haven victims' clothes. This linked Cooper to both murders and the rape.
Forensic scientists found glove fibres from the branches that had been used to hide the Dixon's bodies and on tapings taken from their bodies. This linked Cooper to the murder scene, as it was known that he had thrown away a glove in hedge near his house, found amongst jewellery from his burglaries.Balaclava
Fibres from the balaclava worn by Cooper during the attacks were found amongst floor sweepings taken from a shed belonging to him.
In an interview with Cooper, police were alerted to the potential relevance of the shotgun used in the Sardis robbery. The forensic team found that the gun had been repainted. Below the layers of paint was DNA matching Peter Dixon's profile.
Cooper also stole keys from his victims - 503 sets of keys were recovered from his property and cess pit, including keys stolen during the course of burglaries. They included a key from a property belonging to Richard and Helen Thomas.
Armed with the evidence, police arrested and charged John Cooper. After a nine week trial, the man described as "highly predatory" by the judge was convicted of two double murders, rape and a sexual assault and five attempted robberies. Twenty five years of painstaking work by the police and the forensic team had finally delivered justice to Cooper's victims and families.