Cagefighter murdered teacher ex-partner after discovering her relationship with boy, court hears

Paul Robson may have stamped on and kicked Caroline Kayll, leaving her with fatal brain injuries, jurors told

CCTV shows Paul Robson at a service station on the M74 travelling from Glasgow towards Linton, Northumberland, where Caroline Kayll was murdered (Crown Prosecution Service/PA)

A cagefighter murdered his teacher ex-partner after blackmailing her about a sexual relationship she was having with a 15-year-old boy, a court has heard.

Former convict Paul Robson, 50, carried out a vicious attack on Caroline Kayll, 47, and the teenager at her home in Linton, Northumberland, last November, Newcastle Crown Court heard.

He may have stamped and kicked on her, leaving her with unsurvivable brain injuries, as well as chopping off her hair in clumps, cutting up her clothes and slashing her buttocks, jurors were told.

Injuries to her eyes and neck bruising indicated she may also have been strangled, the court heard.

Mr Robson also repeatedly attacked the boy with scissors and a meat cleaver, and sprayed both him and Kayll with ammonia. He then stole their phones and later updated her social media, pretending to be her, while he was on the run, jurors were told.

The former MMA fighter denies murdering the former prison officer, with whom he had a secret relationship while he was behind bars in HMP Northumberland, as wakk as blackmail and the attempted murder of the boy, who cannot be identified because of his age.

Caroline Kayla, 47, worked as a prison officer and then prison teacher (Northumbria Police/PA)

The case has been heard throughout the week but can only be reported now after a judge lifted reporting restrictions following the completion of the evidence given by the teenager.

Mr Robson claims it was the boy who attacked Kayll, something the teenager denied when he was cross-examined.

The defendant and Kayll, who was separated from her prison officer husband, had lived together in Linton but split up weeks before the murder. He found out she had started a relationship with the boy, whom she said in texts that she loved.

Nicholas Lumley QC, prosecuting, said Mr Robson then had a hold over her, saying: "He knew things about her which she would not want to be made public."

She confided in a friend that Mr Robson was blackmailing her for £35,000 and that her ex was "going to ruin her" and tell her school, the jury heard.

In a period of just 10 days in November, she transferred £29,000 to Robson and took out a £10,500 loan, having previously been solvent.

Days later, Mr Robson sent a series of messages telling their former neighbour about Kayll's relationship with the boy, adding that he was "losing his rag", Mr Lumley said.

On 15 November, Mr Robson drove three hours from Glasgow to Linton, having bought a locksmith's bar, a magnetic GPS car tracker, screwdrivers, pliers, a wrench and the ammonia which he decanted into a washing up bottle.

The powerfully built defendant wore heavy boots and CCTV showed him "prowling" outside her house, the court was told.

Witnesses heard a female voice shout "get out" and later that evening Mr Robson knocked on his former neighbour's house to say "Caroline was in a bad way", Mr Lumley said.

Nurse Barbara Lee immediately went round and she told the court she saw lots of blood and hair in the house, and found Kayll face-down.

Also in the house was the teenage boy, who was in shock and was vomiting blood, "scared and frightened", she said.

Ms Lee attempted CPR until police and paramedics arrived, and Kayll was taken to hospital in Newcastle where tests showed her brain was catastrophically injured.

Mr Robson stole his two victims' phones leaving them no way to call for help, the court heard.

"The actions of a vindictive man, but a jealous man as well," Mr Lumley said.

Mr Robson wanted to use their phones to find out what they had been saying to each other, and posted messages on her Facebook account about the affair with the schoolboy, Mr Lumley said.

Robson also emailed her ex-husband, posing as Kayll, while she was on a life-support machine in hospital, the court heard.

Estranged husband Ian Kayll told the court receiving the email was "quite chilling".

When Mr Robson was arrested and interviewed, he did not answer detectives' questions but in a prepared statement said he was "broken" by her death and claimed someone attacked him when he visited her home.

Mr Lumley told jurors the way Mr Robson and Kayll got together was "a little unusual," saying their relationship behind bars had been secret and "clandestine".

She had worked as a prison officer and then prison teacher and separated from her husband in 2018.

Kayll and Mr Robson "resumed" their relationship "in the outside world" when he was released in autumn 2018, the prosecution said. But they split in 2020, leaving her upset.

Mr Lumley told the jury her subsequent relationship with the 15-year-old was against the law, and she told "white lies" to hide the truth.

Under cross-examination the boy agreed they had argued on the day she died over her plans to meet a male friend.

Kayll texted him: "There's no-one else, I love you."

James Mulholland QC, defending, asked the teenager a series of questions, suggesting the boy had attacked Kayll, which he denied.

Additional reporting by PA