How a murderer was betrayed by his victim’s fingernails

Two murderers who killed their partners in Valentine’s Day attacks tried to hide their crimes but were betrayed by their own body language, a sensational new documentary reveals.

The first is Paul Dyson who strangled girlfriend Joanne Nelson at their home in Hull, in 2005, before dumping her body 75 miles away. Days after reporting her missing, Dyson appeared in an emotional TV interview, appealing for help to find her. But fresh expert analysis reveals how it was all for show. Dyson was in fact ‘squeezing’ out tears – and exaggerating his sobs in an attempt to conceal his heinous crime.

The interview also gave detectives investigating the disappearance a key piece of evidence: the camera picked up crescent-shaped fingernail marks on Dyson’s hands that had been left by Joanne as she desperately fought for her life. 

The second case is of John Tanner, who murdered his Oxford University girlfriend Rachel McLean in 1991 after claiming he flew into a rage when she accepted his proposal but later changed her mind. He then hid her body under the floorboards.

Days after she was last seen, Tanner took part in a police press conference in which he played the role of the distressed boyfriend desperate to find her. However body language experts reveal how he was unconsciously signalling his deception – including a head shake that indicated he knew she was dead. 

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Paul Dyson strangled girlfriend Joanne Nelson, pictured together, at their home in Hull, in February 2005, before dumping her body 75 miles away. He claimed she had gone missing

John Tanner murdered his Oxford University girlfriend Rachel McLean, pictured, in 1991 after claiming he flew into a rage when she accepted his proposal but later changed her mind

John Tanner murdered his Oxford University girlfriend Rachel McLean, pictured, in 1991 after claiming he flew into a rage when she accepted his proposal but later changed her mind

The startling revelations are among those made in Friday night’s episode of Faking It: Tears of a Crime, which examines how killers tried to get away with murder in some of the world’s most high profile criminal cases.

Experts in linguistics, body language and criminal profiling analyse press conferences and interviews to reveal how even the most calculated and confident killers can still give away clues to their guilt. 

Paul Dyson 

Fighting back tears, Paul Dyson made a tearful plea for his girlfriend Joanne Nelson’s safe return just days after he had reported her missing from their home in Hull. 

However his emotional appearance was not all it seemed – and not even his tears were real, according to body language expert Cliff Lansley.  

Emotional: Days after reporting girlfriend Joanne missing from their Hull home, Dyson agreed to a TV interview with a local news crew in which he tearfully appealed for her safe return

Emotional: Days after reporting girlfriend Joanne missing from their Hull home, Dyson agreed to a TV interview with a local news crew in which he tearfully appealed for her safe return

Deception: However expert analysis of Dyson's body language reveals he was not closing his eyes but 'squeezing' them in order to force out tears and convince others of his innocence

Deception: However expert analysis of Dyson’s body language reveals he was not closing his eyes but ‘squeezing’ them in order to force out tears and convince others of his innocence

Analysing the footage, he said: ‘He is squeezing [his eyes] and one of the tactics that an individual can use is to squeeze the eyes to try and create the tears to try and get them to run down the cheek to support the display of sadness. 

‘He is [also] snivelling. He is attempting to show sadness but we will notice now the brows have dropped. He is not in a sad state anymore but he is trying to continue the act of portraying he’s distressed and concerned and sad. 

‘He is clearly attempting to make himself cry or to create tears or create sounds which people might judge to be sadness.’ 

The fingernail marks that reveal his victim’s desperate struggle for life 

Dyson did not notify police before he agreed to take part in a televised interview with a local news team. The first time detectives knew it had taken place is when they saw the report on TV.

However the interview provided Ray Higgins, the head of the major incident team in Humberside Police, with a crucial piece of evidence: a shot of Joanne’s fingernail marks on the back of his hands.

He explained: ‘In the interview, there was two marks on his thumbs. I knew from dealing with other previous assaults and murders that involved strangulation the first thing a victim will do is to try and pull those hands away from their neck. 

Crucial evidence: While watching a recording of Dyson’s TV interview Ray Higgins, the head of the major incident team in Humberside Police, also spotted what appeared to be two crescent-shaped fingernail marks on the back of Dyson’s hand (one circled)

Final moments: It later emerged that Miss Nelson, pictured in fancy dress, left the marks as she struggled to remove Dyson's hands from her neck

Final moments: It later emerged that Miss Nelson, pictured in fancy dress, left the marks as she struggled to remove Dyson’s hands from her neck

‘Sometimes in doing so, they can leave sort of crescent shaped fingernail marks in the skin of the offender and certainly in this particular case, when the news crew zoomed in on Dyson’s hands, you could see quite clearly what appeared to me, to be two similar crescent shaped marks on the back of his thumbs.

‘That was the first time I’d been aware of those marks on the back of his thumbs.’

Dyson, then 31, was eventually turned into police after he told a friend he strangled Miss Nelson after an argument about the laundry at their home.

Calculated: After killing Miss Nelson, pictured, Dyson he went to a nearby shop and bought bin bags, rubber gloves and disinfectant, in a bid to conceal her body and any traces of the killing at their home

Calculated: After killing Miss Nelson, pictured, Dyson he went to a nearby shop and bought bin bags, rubber gloves and disinfectant, in a bid to conceal her body and any traces of the killing at their home

His friend then told Dyson’s mother who contacted police with her concerns. 

Shortly after murdering Miss Nelson, Dyson he went to a nearby corner shop and bought bin bags, rubber gloves and disinfectant spray, in a bid to conceal her body and any traces of the killing at their home. 

He then drove to his mother’s and collected a garden fork, in order to bury the body. 

Agonising wait: Dyson claimed he could not remember where he had buried Miss Nelson's body, sparking a widespread police search, pictured 

Agonising wait: Dyson claimed he could not remember where he had buried Miss Nelson’s body, sparking a widespread police search, pictured 

Dyson drove from Hull to Howden to fill up with petrol and from there took the body 75 miles away, to isolated woodland near Hovingham in North Yorkshire, where he carried her body around 250 yards until he found a concealed dip in the pine trees. 

He later claimed he could not remember where he had buried the body, sparking a massive police search and prolonging the agony for Miss Nelson’s family.

In November 2005, Dyson pleaded guilty to murdering Joanne, and was jailed for life, with a minimum term of of 16 years. The judge said he’d carried out an unforgivable and callous act of deception. 

 

John Tanner

Colin Sutton, Ex-Senior Investigating Officer for the Metropolitan Police, explained how John Tanner was almost ‘cocky’ when he came to face the press, some 15 days after Rachel, his girlfriend of two years, had apparently gone missing. 

He said: ‘He was almost making jokes while he was there, he was smiling and smirking, I think taken as a whole his behaviour was just too confident.’

However unbeknownst to Tanner, police officers had tipped off reporters that he was under suspicion and encouraged them to put him on the spot. 

Under pressure: Tanner at the press conference days after Rachel was murdered. Reporters were tipped off by police that they had suspicions about his involvement with the murder

Under pressure: Tanner at the press conference days after Rachel was murdered. Reporters were tipped off by police that they had suspicions about his involvement with the murder

While Tanner remains calm and collected on the surface, the first cracks begin to show as soon as he is under pressure. 

Body language expert Cliff Lansley explained: ‘We can immediately see a rolling of the lips. This is a reliable indicator of anger. He’s pressing them together… but he’s also rolling the lips in, so the margins, the red margins of the lips have disappeared inside the mouth. 

Widespread search: Rachel McLean was reported missing by a university tutor

Widespread search: Rachel McLean was reported missing by a university tutor

‘This is very hard to do without pressing the lips tightly, so to move them in and press them is a reliable indicator of anger.’

The signals continue when he begins to describe Rachel, who was an English student at St Hilda’s college. 

Analysing the footage, Mr Lansley continued: ‘He’s going to describe her personality, and he’s closed his eyes. When you see an eye closure and you hear a positive statement, it almost cancels that statement out. 

‘It’s a distancing technique, that when we’re saying something unpleasant, one way of managing and handling that is to remove ourselves away from it, either physically, with a low volume, or by closing the eyes. Here we see the eye closure.’

One of the most telling moments is when Tanner unconsciously shakes his head while talking about Rachel’s future. 

Mr Lansley added: ‘He’s saying she’s got everything to go forward for her, now she’s dead, that’s not the case, and he gives that away with a little head shake, “no”. So while he’s saying she’s got everything to live for and everything to go forward for, his body is saying this is all wrong and it’s lies.’

Bold: Tanner, left, took part in a re-enactment of Rachel's final moments with an actress, right

Bold: Tanner, left, took part in a re-enactment of Rachel’s final moments with an actress, right

Possessive rage: How John Tanner murdered girlfriend Rachel McLean

Bright future: Rachel Mclean

Bright future: Rachel Mclean

In 1989, Rachel McLean, then 18, moved to Oxford from her home in Blackpool, Lancashire, to take up her place to study English at St Hilda’s College. 

On her 19th birthday, Rachel met John Tanner, a British-born New Zealander who was two years older and studying at Nottingham University more than 100 miles away. 

While they initially appeared happy to be in a long-distance relationship, Rachel’s passions faded as the months wore on. Tanner was possessive and grew increasingly suspicious of what Rachel might have been doing when he was not there.

Forensic psychologist Kerry Daynes explained it was likely this possessiveness that led Tanner to kill Rachel, explaining: ‘He was driven by two things: one, jealousy… and, rage – rage at being rejected.’

Tanner strangled Rachel at her Oxford student home before wrapping her body in a carpet and stashing it beneath the floorboards of the house. She was reported missing by a tutor when she failed to turn up for an exam five days later. When the police searched her flat it seemed she had vanished. 

Tanner claimed he last saw Rachel when she dropped him off at the train station and kissed him goodbye.

Rageful: Forensic psychologist Kerry Daynes explained was likely to be Tanner's possessiveness that led him to kill Rachel. Pictured, the couple together

Rageful: Forensic psychologist Kerry Daynes explained was likely to be Tanner’s possessiveness that led him to kill Rachel. Pictured, the couple together

Police had their suspicions and organised a press conference where they tipped off reporters, hoping Tanner would crack under pressure. However he only grew more confident and even took part in a reconstruction of how Tanner had described Rachel’s final moments at the train station.

However a viewer phoned in and said she had seen Tanner at the station but that he had been alone. It was then his story started to unravel. 

Two weeks after police initially searched Rachel’s house they returned to rip up the floorboards and found her body wrapped in a carpet.  

At his trial, Tanner pleaded not guilty to murder – arguing that he’d strangled Rachel as a result of extreme provocation when she had accepted his marriage proposal and later changed her mind. 

A jury found Tanner guilty of murder and he was sentenced to life in prison. He was freed in 2003 after serving 12 years and has moved back to New Zealand. 

Faking It: Tears of a Crime airs Friday, 10pm on Investigation Discovery 

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