Italy's Supreme Court fines an appellant €5,000 for AI-hallucinated case citations

The problem

A defence lawyer’s appeal to Italy’s Supreme Court of Cassation (a criminal-execution matter seeking revocation of a demolition order) supported its argument with three Court of Cassation precedents. On verification, none of the three said what the appeal attributed to them — the Court found the cited rulings and their principles “inesistenti e non riferibili alle richiamate sentenze” and concluded they “appaiono il frutto di un evidente fenomeno di allucinazione informatica” (an evident phenomenon of computer hallucination), “probabilmente dovuta all’impiego di sistemi di intelligenza artificiale.” No specific AI product was named or adjudicated.

What was built

Not a build. This is a court-origin precedent on AI accountability in litigation. The Terza Sezione Penale (President Luca Ramacci; reporting judge Alessio Scarcella) decided the case on 11 June 2026 and filed judgment no. 23006/2026 on 22 June 2026 (R.G.N. 14371/2026).

The outcome

The Court declared the appeal inadmissible and, under art. 616 cod. proc. pen., ordered the appellant to pay a sum “determinata in via equitativa, di euro 5.000,00 in favore della Cassa delle Ammende” — an amount above the ordinary measure. Its reasoning: “la citazione di giurisprudenza inesistente generata dall’intelligenza artificiale non attenua, ma anzi accentua il giudizio di colpevolezza processuale.” Using an AI tool does not create a liability-free zone; the professional who signs the brief keeps full responsibility to verify the truth, relevance and specificity of the sources. (The €5,000 falls on the appellant/party under art. 616, not as a Bar disciplinary sanction.)

Path to green

A human confirms the record against the Corte di Cassazione register / Cancelleria of the Third Criminal Section: the official raccolta-generale number (23006/2026), the filing date (22 June 2026), and the €5,000 art. 616 order. Both critical facts are already stated verbatim in the signed judgment (byte-tied to Wayback capture 20260725103717) and independently reported by two archive-bound Italian legal-news outlets — EC News (Euroconference) and Servicematica — each stating the €5,000.