What was hallucinated

Fabricated: Case Law | Plaintiff cited a nonexistent Seventh Circuit case; the reporter citation corresponds to an unrelated decision. || Fabricated: Legal Norm | Plaintiff cited a nonexistent FCRA statutory provision; the Court inferred she meant § 1681e(b). || Fabricated: Legal Norm | Plaintiff cited a nonexistent FCRA statutory provision in the complaint. || Fabricated: Case Law | Plaintiff cited a nonexistent Ninth Circuit case; the reporter citation corresponds to an unrelated decision. || Fabricated: Case Law | Plaintiff cited a nonexistent Ninth Circuit case; the reporter citation corresponds to an unrelated decision.

Details

AI UsePlaintiff, opposing motions to dismiss, filed a brief containing three fake federal case citations. Defendants raised the issue in their reply, suggesting use of ChatGPT or a similar tool. Plaintiff did not deny the accusation.Hallucination DetailsThree nonexistent cases were cited. Each cited case name and number was fictitious; none of the real cases matching those citations involved remotely related issues.Ruling/SanctionThe court issued a formal warning to Plaintiff: any future filings containing fabricated citations or quotations will result in sanctions, including striking of filings, monetary penalties, or dismissal. No sanction imposed for this first occurrence, acknowledging pro se status and likely ignorance of AI risks.Key Judicial ReasoningReliance on nonexistent precedent, even by pro se litigants, is an abuse of the adversarial system. The court cited Mata v. Avianca and Park v. Kim as establishing the principle that hallucinated case citations undermine judicial integrity and waste opposing parties’ and courts' resources. Plaintiff was formally warned, not excused.

Sanction teardown · S.D. New York, USA · 2024-07-26

Dukuray v. Experian Information Solutions

What happened

In S.D. New York, 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)

Plaintiff cited a nonexistent Seventh Circuit case; the reporter citation corresponds to an unrelated decision.
Fabricated (Legal Norm)

Plaintiff cited a nonexistent FCRA statutory provision; the Court inferred she meant § 1681e(b).
Fabricated (Legal Norm)

Plaintiff cited a nonexistent FCRA statutory provision in the complaint.
Fabricated (Case Law)

Plaintiff cited a nonexistent Ninth Circuit case; the reporter citation corresponds to an unrelated decision.
Fabricated (Case Law)

Plaintiff cited a nonexistent Ninth Circuit case; the reporter citation corresponds to an unrelated decision.

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

No sanction; Formal Warning Issued

Additional detail

AI UsePlaintiff, opposing motions to dismiss, filed a brief containing three fake federal case citations. Defendants raised the issue in their reply, suggesting use of ChatGPT or a similar tool. Plaintiff did not deny the accusation.Hallucination DetailsThree nonexistent cases were cited. Each cited case name and number was fictitious; none of the real cases matching those citations involved remotely related issues.Ruling/SanctionThe court issued a formal warning to Plaintiff: any future filings containing fabricated citations or quotations will result in sanctions, including striking of filings, monetary penalties, or dismissal. No sanction imposed for this first occurrence, acknowledging pro se status and likely ignorance of AI risks.Key Judicial ReasoningReliance on nonexistent precedent, even by pro se litigants, is an abuse of the adversarial system. The court cited Mata v. Avianca and Park v. Kim as establishing the principle that hallucinated case citations undermine judicial integrity and waste opposing parties’ and courts' resources. Plaintiff was formally warned, not excused.

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/242/Dukuray_v._Experian_US_DC_SDNY_July_26_2024.pdf, via Damien Charlotin's public AI Hallucination Cases Database (CC0).