Sanction teardown · D. Connecticut, USA · 2026-08-04
Barteca Holdings v. Tacobarn
What happened
In D. Connecticut, USA, a filing relied on Open Law; Claude; ChatGPT to help draft legal argument. The court identified the following problems with the citations in that filing:
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False Quotes (Case Law)Misquoted language attributed to Ashcroft v. Iqbal; quoted terms and pin cites incorrect and did not match the cited pages.
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False Quotes (Case Law)Attributed a non-existent quotation to Landscape Forms; the opinion's wording differs from the quoted passage in the brief.
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False Quotes (Case Law)Attributed language about an 'amorphous overall style' to Yurman; the cited page does not contain that phrasing.
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Misrepresented (Case Law)Mischaracterized Streetwise Maps as addressing incontestability; the case does not address that issue as asserted in the brief.
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Misrepresented (Case Law)Erroneous pin cite for the opinion discussing 1-800 CONTACTS and WARBY PARKER (brief cited page 251; correct citation should be pages 249–50).
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Misrepresented (Case Law)Cited Chambers as supporting judicial notice under FRE 201(b); Chambers does not contain that proposition as represented.
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Misrepresented (Case Law)Mischaracterized Cortec as imposing a blanket rule that documents at Rule 12 may only be considered if plaintiff had notice and relied on them; Cortec's holding is narrower and contextual.
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False Quotes (Case Law)Misquoted Fonte and Friedl regarding Rule 12(b)(6) procedure and treatment of materials outside the pleadings; attributed language does not appear as quoted.
Which AI tool
Open Law; Claude; ChatGPT. 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
Monetary Sanction; Bar Referral (monetary penalty: 3500 USD.)
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/2763/Barteca_v._Tacobarn_USA_4_August_2026.pdf, via Damien Charlotin's public AI Hallucination Cases Database (CC0).