Incident Tracker

Harber v Commissioners for HMRC, [2023] UKFTT 1007 (TC)

dismissal

The first reported United Kingdom case of AI-fabricated authorities: before the First-tier Tax Tribunal, litigant in person Felicity Harber cited nine non-existent decisions generated by ChatGPT to argue a reasonable excuse for a capital-gains penalty. The tribunal found the cases fake, dismissed her appeal, and warned of the harm fabricated authorities cause.

Date of decision/order

2023-12-04

Court

First-tier Tribunal (Tax Chamber)

Jurisdiction

UK

AI tool

ChatGPT

Conduct

A litigant in person submitted the names, dates and summaries of nine First-tier Tribunal decisions said to show a reasonable excuse for a late capital-gains disclosure; none of the authorities existed. The tribunal found they had been generated by AI.

Consequence

See outcome

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