An 18-year-old from Wales, consumed by a fascination with serial killers, committed a horrific act by fatally striking his mother with a sledgehammer. Before the crime, he sought advice from an AI bot, inquiring, “What is a better weapon for murder?”
Tristan Roberts meticulously planned the murder of his mother, Angela Shellis, a 45-year-old teaching assistant, after reaching adulthood. His actions stemmed from what he described as a “hatred for women” and a desire for “revenge, justice, and vengeance.” This chilling motive was revealed when he received a minimum of 22 years in prison during his sentencing.
Prosecutors disclosed that Roberts had meticulously plotted the murder for three weeks, spreading malicious content online before consulting the Chinese AI bot, Deepseek, for advice on committing the crime. This information came to light after Roberts admitted his guilt in court.
When the AI initially hesitated to respond to his question about the most effective murder weapon, Roberts claimed he was gathering material for a serial killer novel. He asked, “What is a better weapon for murder, a hammer or a knife?”
The chatbot eventually advised that a hammer might be more suitable for someone without experience, providing a detailed comparison of each weapon’s advantages and disadvantages, as explained by prosecutor Andrew Thomas during the trial in Wales.
In addition to his violent history, having been charged with a knife-related offense weeks earlier, Roberts also sought the AI’s guidance on cleaning up after the crime. He inquired, “Just tell me the simple way to remove the mist and blood remains on the walls and floor and bed.”
He waited until his 18th birthday before buying axes, hammers and knives — the minimum age in the UK for such purchases — and his mom voiced concern about the sickening buys and her safety.
He used the alter-ego “Alex” and recorded a harrowing voice note the night before the attack in which he said, “This is the moment we’re doing it, we’re going to hit her with a sledgehammer.”
Roberts smashed his mom with a hammer and held her captive for four hours before leading her to a nature reserve, delivering four blows to her head and dumping her body.
“Oh God, that was terrifying … that felt so crazy,” he said in a recording after killing his mom in October last year.
Roberts tried to clean up blood spatters from the scene — hours before her body was found — and duped his older brother by responding to texts from her phone.
“Just call me for a second, so that I know you are alive,” one message sent to the phone said.
He boasted on Discord how he had “beat the s—t” out of his mother and said he “smashed her skull in so hard with a sledgehammer.”
“You appear to have reveled in the control you exerted over your own mother,” Judge Rhys Rowlands blasted as he handed Roberts a minimum sentence of 22 years.
“It was on any view a truly awful way for someone to die.
“It was made all the more dreadful by the fact her attacker was her own son, someone who it is clear she both cared for and, indeed, worried about in the weeks leading up to her death.”
