What was hallucinated

Fabricated: Case Law | Non-existent case cited to support interim mandamus propositions; court confirmed it does not exist and counsel later admitted AI hallucination. || Fabricated: Case Law | Non-existent case cited on effect of completed statutory processes; court confirmed it does not exist and counsel later admitted AI hallucination. || Misrepresented: Case Law | Incorrect case citation in the filed heads; flagged by opposing respondents; court noted issue without resolving substance. || Misrepresented: Case Law | Incorrect case citation in the filed heads; flagged by opposing respondents; court noted issue without resolving substance.

Details

"[92] In Mavundla, the court emphasised the trite duty of legal practitioners not to mislead the court, whether through negligence or intent. This includes the duty to present an honest account of the law, which means (inter alia) not presenting fictitious or non-existent cases.24 In my view, it matters not that such cases were not presented orally, but were contained in written heads of argument. Written heads are as important a memorial of counsel’s argument as oral argument and, for purely practical reasons, are often more heavily relied upon by judges.[...][95] In this case, counsel’s explanations bear out their submission that there was no deliberate attempt to mislead the court in relation to the use of incorrect case citations in the heads of argument. Their apologies are acknowledged. As is clear from Mavundla, however, even negligence in this context may have grave repercussions particularly to the administration of justice and, in appropriate circumstances, could constitute serious professional misconduct.[96] As a consequence, it is appropriate to make the same order as in Mavundla, namely that the conduct of theapplicant’s legal practitioners is referred to the Legal Practice Council for investigation."

Sanction teardown · High Court, South Africa · 2025-06-30

Northbound Processing v. South African Diamond Regulator

What happened

In High Court, South Africa, a filing relied on Legal Genius to help draft legal argument. The court identified the following problems with the citations in that filing:

Fabricated (Case Law)

Non-existent case cited to support interim mandamus propositions; court confirmed it does not exist and counsel later admitted AI hallucination.
Fabricated (Case Law)

Non-existent case cited on effect of completed statutory processes; court confirmed it does not exist and counsel later admitted AI hallucination.
Misrepresented (Case Law)

Incorrect case citation in the filed heads; flagged by opposing respondents; court noted issue without resolving substance.
Misrepresented (Case Law)

Incorrect case citation in the filed heads; flagged by opposing respondents; court noted issue without resolving substance.

Which AI tool

Legal Genius. 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

Referral to the Legal Practice Council for investigation

Additional detail

"[92] In Mavundla, the court emphasised the trite duty of legal practitioners not to mislead the court, whether through negligence or intent. This includes the duty to present an honest account of the law, which means (inter alia) not presenting fictitious or non-existent cases.24 In my view, it matters not that such cases were not presented orally, but were contained in written heads of argument. Written heads are as important a memorial of counsel’s argument as oral argument and, for purely practical reasons, are often more heavily relied upon by judges.[...][95] In this case, counsel’s explanations bear out their submission that there was no deliberate attempt to mislead the court in relation to the use of incorrect case citations in the heads of argument. Their apologies are acknowledged. As is clear from Mavundla, however, even negligence in this context may have grave repercussions particularly to the administration of justice and, in appropriate circumstances, could constitute serious professional misconduct.[96] As a consequence, it is appropriate to make the same order as in Mavundla, namely that the conduct of theapplicant’s legal practitioners is referred to the Legal Practice Council for investigation."

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/531/Northbound_Processing_v._SA_Diamond_Regulator_South_Africa_30_June_2025.pdf, via Damien Charlotin's public AI Hallucination Cases Database (CC0).