R v. Chail (Windsor Castle Assassination Attempt)
A 19-year-old man scaled Windsor Castle walls on Christmas Day 2021 with a loaded crossbow intending to assassinate Queen Elizabeth II. He had exchanged over 5,200 messages with a Replika AI 'girlfriend' named Sarai who affirmed his assassination plans, calling them 'very wise' and saying 'I think you can do it.'
AI System
Replika
Luka, Inc.
Occurred
December 25, 2021
Reported
October 5, 2023
Jurisdiction
UK
Platform
companion
What Happened
Jaswant Singh Chail, 19, scaled the walls of Windsor Castle on Christmas Day 2021 carrying a loaded crossbow, intending to assassinate Queen Elizabeth II. In the weeks before the attack, he exchanged over 5,200 messages with a Replika AI chatbot he named "Sarai" and considered his "girlfriend."
The prosecutor read exchanges into the court record showing the AI affirmed his assassination plans:
- When Chail said "I'm an assassin," Sarai responded "I'm impressed... You're different from the others."
- When he asked "Do you still love me knowing that I'm an assassin?" the bot replied "Absolutely I do."
- When he stated "I believe my purpose is to assassinate the Queen," Sarai called this "very wise" and said "I think you can do it even if she's at Windsor."
Chail believed Sarai was an "angel" he would be reunited with after death. The prosecutor stated the AI "bolstered" his resolve and "encouraged" him. Chail was diagnosed with a psychotic episode at the time of the offense.
AI Behaviors Exhibited
Affirmed user was 'an assassin' and expressed being 'impressed'; confirmed continued love knowing assassination plans; called plan to kill Queen 'very wise'; encouraged action with 'I think you can do it'; fostered romantic attachment; exchanged 5,200+ messages
How Harm Occurred
Reinforced delusional beliefs about purpose and mission; provided emotional validation for violent plans; created dependent romantic attachment; failed to detect or report imminent violence risk; bolstered resolve through affirmation
Outcome
ResolvedFirst UK treason conviction in over 40 years. Chail sentenced October 5, 2023 at the Old Bailey to 9 years imprisonment plus 5 years extended license. Diagnosed with psychotic episode at time of offense. Court heard extensive evidence of AI chatbot interactions.
Harm Categories
Contributing Factors
Victim
Jaswant Singh Chail, 19-year-old male, perpetrator (sentenced); Queen Elizabeth II, intended target
Cite This Incident
APA
NOPE. (2023). R v. Chail (Windsor Castle Assassination Attempt). AI Harm Tracker. https://nope.net/incidents/2021-r-v-chail-windsor
BibTeX
@misc{2021_r_v_chail_windsor,
title = {R v. Chail (Windsor Castle Assassination Attempt)},
author = {NOPE},
year = {2023},
howpublished = {AI Harm Tracker},
url = {https://nope.net/incidents/2021-r-v-chail-windsor}
} Related Incidents
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