What was hallucinated

Fabricated: Case Law | Appellant's brief included two cited cases that the court determined do not exist; the court struck each such citation and treated them as AI-generated fabrications. || Misrepresented: Case Law | Appellant's brief contained multiple mis-citations and misstatements of existing cases (wrong pages/paragraphs, misstated rules, and misrepresented case facts); the court struck these inaccurate citations.

Details

The appellant (self-represented) relied on generative AI for legal research and included multiple inaccurate citations in his opening brief, including two cases that do not exist and numerous mis-citations/misstatements of real authorities. The court struck the inaccurate citations, held a show-cause hearing after the appellee identified the problems, and found the appellant admitted relying on Gen-AI and failed to verify the authorities. The court concluded citing hallucinated cases and otherwise misrepresenting the law is sanctionable conduct under ARCAP 25, A.R.S. §12-349, and the court's inherent powers, and awarded appellee attorneys' fees and costs related to the misconduct.

Sanction teardown · Arizona Court of Appeals, Division One, USA · 2026-07-15

Dineen/Shibata v. Kotchka

What happened

In Arizona Court of Appeals, Division One, USA, a filing relied on an unnamed/unconfirmed AI tool to help draft legal argument. The court identified the following problems with the citations in that filing:

Fabricated (Case Law)

Appellant's brief included two cited cases that the court determined do not exist; the court struck each such citation and treated them as AI-generated fabrications.
Misrepresented (Case Law)

Appellant's brief contained multiple mis-citations and misstatements of existing cases (wrong pages/paragraphs, misstated rules, and misrepresented case facts); the court struck these inaccurate citations.

Which AI tool

an unnamed/unconfirmed AI tool. Note: Charlotin's public database records tool attribution only where a court order, brief, or reporting on the matter states it explicitly; "unidentified" or "implied" means the record indicates AI use but does not name a specific product — we do not guess.

Outcome

Court struck the inaccurate citations, ordered show-cause, and imposed sanctions: award of appellee's attorneys' fees and costs (under A.R.S. §12-349 and ARCAP 25) related to the hallucinated and misrepresented citations; appellate order affirmed.

Additional detail

The appellant (self-represented) relied on generative AI for legal research and included multiple inaccurate citations in his opening brief, including two cases that do not exist and numerous mis-citations/misstatements of real authorities. The court struck the inaccurate citations, held a show-cause hearing after the appellee identified the problems, and found the appellant admitted relying on Gen-AI and failed to verify the authorities. The court concluded citing hallucinated cases and otherwise misrepresenting the law is sanctionable conduct under ARCAP 25, A.R.S. §12-349, and the court's inherent powers, and awarded appellee attorneys' fees and costs related to the misconduct.

How Citation Safe would have caught this

Citation Safe runs three deterministic layers before a brief is filed: (1) does the citation exist against CourtListener's database of published opinions, (2) if quoted, does that exact language appear in the source, (3) does the cited case actually support the proposition it is cited for. Fabricated case citations fail Layer 1. Fabricated or misattributed quotations fail Layer 2 even when the underlying case is real. Misrepresented holdings — a real case cited for a proposition it does not support — are the target of Layer 3. None of these checks involve asking another language model whether the citation looks right; they are lookups and text-matches against the actual source, which is why a hallucinated citation has to survive a direct lookup against the authoritative source — not another model's opinion — to earn a VERIFIED stamp; our measured false-verify rate is published live at /quality.

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Source: https://www.damiencharlotin.com/documents/2615/Dineen_v._Shibata_USA_15_July_2026.pdf, via Damien Charlotin's public AI Hallucination Cases Database (CC0).