AI-hallucinated case citations have moved from novelty to a core challenge for the courts, prompting complaints from judges that the issue distracts from the merits of the cases in front of them.
The growing burden placed by artificial intelligence became clear in 2025, two years after the first prominent instance of fake case citations popped up in a US court. There have been an estimated 712 legal decisions written about hallucinated content in court cases around the world, with about 90% of those decisions written in 2025, according to a database maintained by Paris-based researcher and law lecturer Damien Charlotin.
“It just is metastasizing in size,” said Riana Pfefferkorn, a policy fellow at the Stanford Institute for Human-Centered Artificial Intelligence. “So, it seems like this is something that is actually becoming a widespread enough nuisance that it will merit treatment as a core problem.”
- Date Published:12.29.2025
- Original Publication: Bloomberg Law