The High Court has issued a stark warning to UK lawyers over the misuse of artificial intelligence after two cases were blighted by fictitious case-law citations. In a ruling on Friday, Dame Victoria Sharp, President of the King's Bench Division, said there were “serious implications for the administration of justice” and that lawyers misusing AI could face sanctions including contempt of court proceedings.
In one case, a claim for £89m in damages against Qatar National Bank, the claimants made 45 case-law citations, 18 of which were completely fictitious. The claimant admitted using publicly available AI tools, and his solicitor accepted citing the sham authorities. In a separate case, Haringey Law Centre cited phantom case law five times when challenging Haringey Council over temporary accommodation. The barrister involved denied using AI but said she may have inadvertently done so while using Google or Safari.
Dame Victoria called on the Bar Council and the Law Society to take urgent action to curb the problem. She said AI tools “can produce apparently coherent and plausible responses” but those responses “may turn out to be entirely incorrect” and “may cite sources that do not exist”. Ian Jeffery, chief executive of the Law Society of England and Wales, said the ruling “lays bare the dangers of using AI in legal work”.
The cases are not isolated. In 2023, a UK tax tribunal heard from an appellant who provided nine bogus historical tribunal decisions, admitting she may have used ChatGPT. In a US case the same year, two lawyers and their firm were fined $5,000 after citing seven fictitious cases generated by ChatGPT.
