What happened

Felicity Harber used a generative AI system - considered likely to have been ChatGPT - to support her legal case, according to the First-tier Tribunal.

The Tribunal determined that all nine cited cases cited by Harber had been fabricated and lacked any presence in legitimate legal databases.

The citations exhibited characteristics typical of AI-generated content, such as American English spelling and repetitive phrases.

Why it happened

Judge Anne Redston acknowledged that Harber was unaware of the fakeness of the cases and did not know how to verify their authenticity. 

Despite this, her appeal was dismissed on the grounds that her mental health condition did not prevent her from seeking tax advice or contacting HMRC. Harber received a penalty of GBP 3,265 for failing to notify HMRC of her liability after selling a property.