Brianna Ghey: How could two bright children from stable homes go on to commit such a brutal murder?

Brianna was stabbed 28 times – Chris Neill

In the dock of a Manchester courtroom, two 16-year-olds sit staring at their feet. The girl shakes with fear, the boy fidgets with a toy. Neither one looks at the other. Over four weeks they will each cast themselves as an innocent bystander, manipulated by a murderer. They’ll blame each other, they’ll twist the truth, they’ll seem at times like frightened, disturbed children – at others like pure fantasists. No matter how extensive the evidence of a calculated murder plot, no matter the paper trail they left lying around so casually (the unhinged texts, the hunting knife covered in blood, the handwritten plan to kill), boy Y and girl X will continue to deny murdering Brianna Ghey. In the end, a jury will have heard more than enough to be convinced of their guilt.

But as the pair now face life sentences for the brutal killing of an anxious young girl – an outsider, like both of them – the question remains: why? Why would two bright teenagers from what were, by all accounts, stable homes go on to become killers?

It’s impossible to make sense of how a child could be moved to murder, and children boy Y and girl X both were. As minors, they were given more leeway than an adult defendant would be in court, from shorter days to frequent breaks and fidget toys when they felt anxious. But characterising boy Y and girl X (as they will be known for just six more weeks, before a judge names them for the first time in February) isn’t straightforward.

Should they be seen as vulnerable innocents whose young minds were corrupted by the horrific things they encountered while stumbling around the dark web? Were they complicated young people with untreated neurodiversity? (Both were diagnosed after their arrest with autism spectrum disorder.) Was she the brains and he the helpless accomplice acting on her whim? Were they both violent and angry; were they of sound mind when they stabbed Brianna 28 times; were they just plain evil?

The contents of their phones reveals a friendship of two halves. The pair had known each other since they were 11. Both have been described as clever and “high functioning” – boy Y, particularly, was a high achiever. Since his arrest he has passed eight GCSEs, is teaching himself his A-Levels and wants to study for a university degree in prison. They attended the same school in Culcheth before girl X was expelled over a “cannabis incident” – she had given drugs to a younger pupil.

They were teenagers who talked about all the usual obsessions: crushes, friends, teachers. They were close. Close enough to share the darkest possible secrets – the “less innocent topics”, said Deanna Heer KC, prosecuting. Among all the usual memes and gossip, there were also darkly casual discussions of murder.

The pair meticulously planned Brianna’s murder – CPS

“The messages they exchanged show that they were preoccupied with violence, torture and death and record them discussing how they wanted to kill people they knew.

“If that was not an unusual way for two teenagers to speak to one another, the messages demonstrate how, over time, they encouraged one another to think about how they would actually carry out a killing.”

They spoke about murder as carelessly as if they were talking about their homework. Their possible targets extended beyond Brianna. In November 2022, the pair discussed killing a teenage boy, known as boy M, after boy Y became worried he was getting too close to a girl he fancied. Girl X told him: “You can restrain him as I kill him so it’s easier.” In December, she confided that she had been watching videos of people being murdered and tortured on the dark web. Far from being shocked, the pair discussed whether potassium cyanide, sarin or ricin was a better way to kill someone.

In court, girl X admitted enjoying “dark materials” online and said she often fantasised about murdering someone. She bonded with boy Y, she said, over their “similar interests”.

Brianna, who girl X had become friends with after she complimented her eyeliner and who she hung out with after school, was first mentioned in their messages on December 15, 2022. Girl X sent a message to boy Y, which read: “I’m obsessed over someone I know but don’t have feelings for them… She’s called Brianna… I don’t know how to explain. Also she has a d— lol”.”

Boy Y responded: “I don’t think you’re necessarily in love but I think you’re more curious and intrigued by its unnatural nature.”

Girl X later admitted to the court that she was attracted to Brianna, though she was adamant she did not target her because she was transgender. Three days later, she messaged boy Y, saying she had hallucinated that she was covered in the blood of a murder victim and could “hear him screaming” while she stood by “smiling and holding the knife”. Two weeks later, on January 1, boy Y sent her a picture of a knife. It was the first step in turning their fantasies into reality. The 5in-long hunting knife would later be used to stab Brianna.

Girl X wrote out a plan. On February 3, 10 days before the murder, she sent a photo of it to the boy. It was headed: “Saturday 11 February 2023. Victim: Brianna Ghey.”

The hunting knife used to kill Brianna – PA

“Meet [Y] at wooden posts 1pm. Walk down to library … bus stop. Wait until Brianna gets off bus then the 3 of us walk to linear park. Go to the pipe/tunnel area. I say code word to [Y]. He stabs her in the back as I stab her in the stomach. [Y] drags the body into the area. We both cover up the area with logs etc.”

They carried out that plan exactly.

Det Ch Supt Mike Evans of Cheshire Police said it became clear early on in the investigation that the pair believed they wouldn’t be found out – their “arrogance” was startling. “Their downfall has been their confidence or arrogance around the fact that they thought they could take another human life and then thought there would be no comeuppance.”

One message shows girl X reassuring boy Y he wouldn’t be caught as the police in their area were useless. On the day after they murdered Brianna, she posted a tribute to her “amazing friend” on Snapchat. “Brianna was one of the best people I have ever met and such an amazing friend it’s so f—— sickening what got done to her.”

But was it callous arrogance or a sign of genuine delusion – a symptom of trauma, perhaps, or undiagnosed autism? The court heard girl X had traits of autism and ADHD; boy Y had been diagnosed with selective mutism. Both were given those assessments after their arrest.

“People who have autism can still differentiate between right and wrong, they can still feel guilt,” says Dr Dara Mojtahedi, an expert in forensic and criminal psychology at the University of Bolton. “They fit the signs of individuals who are sadistic.”

When considering sentencing, the extent to which the murder they carried out was planned should be taken into account, says Dr Ava Green, lecturer in forensic psychology at City, University of London.

“What was particularly striking for me was how much detail and planning the murder took before it actually happened. That suggests there was a sadistic, malicious intent – a very meticulous plan to murder this girl in the most heinous way possible. […] They were so delusional that not only did they murder, they thought they were going to get away with it.”

They were planning more attacks too – when police searched their homes they uncovered a kill list. When sentencing in February, that “sadistic urge to kill” should be considered, says Green, along with “the ruminations, the arrogance, the blame-shifting tactics”.

Neither showed remorse in court, though girl X seemed more fearful, more obviously moved by what was happening. One assessment of boy Y and girl X put forward by his defence is that she was the cold mastermind while he was the vulnerable one, manipulated into carrying out her bidding. Richard Littler KC, defending boy Y, said: “He believed she was a fantasist. He went along with her stories.

“She did turn her fantasy into reality. She wrote the play, she directed it, she produced it, she stage-managed it. Boy Y was an extra.”

In court, she dressed demurely in cardigans and dresses, her hair down, a locket around her neck, her voice so quiet she had to be told to raise her voice. The boy appeared largely emotionless. Jurors were told that following his arrest, he had “gradually stopped speaking” to anyone apart from his mother. He sat behind a desk in a sideroom off the court, typing his answers on a keyboard which were then spoken by an intermediary sitting next to him.

However they appeared in court, the pair’s internet searches in the hours after the murder are striking. Boy Y’s: “Six ways to calm your fight or flight response.” Girl X’s: “Leather flare pants and leather bell bottoms.”

Whoever stabbed Brianna (it is still not known which one physically killed her), there is a sense that neither one would have acted alone. This was a coming together of two fantasists who were at their most dangerous when they egged each other on. In cases where there are two killers, it’s common to have a ringleader, says Dr Mojtahedi. “There is often one person leading from the front and one person being carried through the process.

“I think that’s the case here. I think there was one person who was more motivated.”

Det Ch Supt Evans was asked what he believed boy Y and girl X’s motive was. “Fun,” he suspected, could be the word. “I think they killed her because they wanted to prove that they could.”

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