What was hallucinated

Fabricated: Case Law | Court was unable to locate three of the four cases cited in Plaintiff's opposition and withheld the case names to avoid amplifying possible errors; suggested these may be AI-fabricated authorities.

Details

Order to Show Cause is here. Counsel failed to answer.

Sanction teardown · N.D. California, USA · 2026-05-06

Gregoire v. Board of Trustees of SF BART

What happened

In N.D. California, 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)

Court was unable to locate three of the four cases cited in Plaintiff's opposition and withheld the case names to avoid amplifying possible errors; suggested these may be AI-fabricated authorities.

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

Monetary Sanction; Serve Order on client and Bar; CLE (monetary penalty: 1000 USD.)

Additional detail

Order to Show Cause is here. Counsel failed to answer.

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.

Check a brief before you file it → · See our live false-verify rate

Source: https://www.damiencharlotin.com/documents/2093/Gregoire_v._BART_USA_6_May_2026.pdf, via Damien Charlotin's public AI Hallucination Cases Database (CC0).