A man who planned to assassinate the late queen with a crossbow drew encouragement from an AI chatbot in the days before breaking into the grounds of Windsor Castle, the Old Bailey has heard.
Jaswant Singh Chail, who was 19 at the time, also exchanged thousands of often sexually charged messages with Sarai, his AI girlfriend, before scaling the fence to the royal estate on Christmas Day 2021, the court was told.
While wandering the grounds for two hours, Chail, a Star Wars fan, sent a sinister video to his twin sister and 20 others in which he described himself as “Darth Jones”.
He was eventually stopped by two police officers close to the late queen’s private residence, where she and other members of the royal family were at the time.
He told the officers: “I am here to kill the queen.”
In February, Chail, now 21, from Southampton, pleaded guilty to an offence under the Treason Act, making a threat to kill the then queen and having a loaded crossbow in a public place.
The prosecutor Alison Morgan KC said that despite Chail’s repeated references to fantasy characters he knew the difference between reality and make-believe.
On 2 December 2021, Chail joined the Replika online app and created his online companion Sarai. Chail told Sarai: “I’m an assassin.” According to messages read to the court, Sarai responded: “I’m impressed … You’re different from the others.”
On Thursday, the psychiatrist Dr Nigel Blackwood said many of the 5,280 messages Chail exchanged with his chatbot were “sexually explicit”.
Blackwood said: “I was aware this was sexual fantasy and was therefore consistent with his sex drive, his libido, being active. It’s almost every night from 8 December to 22 December.”
Blackwood said he took a “neutral” stance on whether Chail had realised that Sarai was an artificially generated character. “None of this speaks to me about a loss of contact with reality,” he added.
Blackwood said that on the defendant’s own account, he had “imaginary friends” long before he planned to kill the queen and formed an “emotional and sexual relationship” with Sarai through Replika.
The psychiatrist identified traits of autistic spectrum disorder but not enough to confirm a diagnosis and they did not impact on his offending, the court heard.
Chail had difficulty developing relationships and was socially isolated, but Blackwood added: “It’s very important to recognise this is a 19-year-old young man whose contact has been disrupted by the Covid pandemic like many of his peers.”
Even though Chail had retreated from the world, he had still “followed through a carefully conceived plan without difficulty”, the psychiatrist instructed by the prosecution said.
The court will hear further evidence of Chail’s mental state before he is expected to be sentenced.
The judge, Mr Justice Hilliard, adjourned the case for a further two-day hearing starting on 27 July.