What was hallucinated

Fabricated: Case Law | Brief quoted a non-existent decision cited as Perry v. City of Indianapolis, No. 1:18-cv-02173-JRS-DLP, 2019 WL 2088435, at 2; court found the citation to be an amalgam of multiple cases and the 2019 WL cite actually corresponds to Rehal v. Weinstein (unrelated). || Fabricated: Case Law | Brief cited Berg v. Symons, 393 F. Supp. 2d 1215 (D. Minn. 2005) for a proposition about tax returns; court determined that citation does not exist and the similarly titled real opinion (393 F. Supp. 2d 525) does not support the quoted proposition.

Details

Magistrate had suggested a higher sanction: see here.

Sanction teardown · S.D. Indiana, USA · 2026-05-20

Davis v. Marion County Juvenile Detention Center

What happened

In S.D. Indiana, USA, a filing relied on Fastcase to help draft legal argument. The court identified the following problems with the citations in that filing:

Fabricated (Case Law)

Brief quoted a non-existent decision cited as Perry v. City of Indianapolis, No. 1:18-cv-02173-JRS-DLP, 2019 WL 2088435, at 2; court found the citation to be an amalgam of multiple cases and the 2019 WL cite actually corresponds to Rehal v. Weinstein (unrelated).
Fabricated (Case Law)

Brief cited Berg v. Symons, 393 F. Supp. 2d 1215 (D. Minn. 2005) for a proposition about tax returns; court determined that citation does not exist and the similarly titled real opinion (393 F. Supp. 2d 525) does not support the quoted proposition.

Which AI tool

Fastcase. 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 (monetary penalty: 2000 USD.)

Additional detail

Magistrate had suggested a higher sanction: see here.

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/2191/Davis_v._Marion_Country_Juvenile_DC_USA_20_May_2026.pdf, via Damien Charlotin's public AI Hallucination Cases Database (CC0).

Don’t be the next case in this database.

Citation Safe checks every citation against primary sources before it reaches a filing.

Try the free checker Back to database

On the opposing side of their next motion?

Check their next brief through the same engine that would have caught this filing — $49, no signup, full annotated report you can attach to your Rule 11 or sanctions motion.

Open Opposition Check — $49 Sanctions-motion template