In 2023, a New York court sanctioned lawyers who filed a brief citing cases that did not exist — invented, confidently and fluently, by a chatbot (Mata v Avianca, S.D.N.Y. 2023). It was not the last such case. Courts in several countries have since dealt with AI-fabricated authorities, and the pattern is always the same: the citations look perfect.

Why language models invent cases

A general-purpose language model predicts plausible text. A plausible-sounding citation — right format, right reporter, right era — is often more statistically likely than the messy truth. The model is not lying; it is doing exactly what it was built to do, in a domain where “plausible” and “true” must never be confused.

Why it matters more in law

In most fields a wrong reference is an embarrassment. In law, authority is the argument. A contract analysis that says “this clause is unenforceable” is worthless unless the statute or case behind that statement exists and says what it is claimed to say.

The engineering answer: a verified authority bank

Our approach is structural, not aspirational:

• A curated bank of authorities — the statutes and leading cases for each jurisdiction we cover — checked against primary sources: legislation.gov.uk, the National Archives’ Find Case Law, CourtListener, and official legislature sites.
• Verbatim citation only. The engine may cite from the bank word-for-word. It is instructed, hard, never to invent a citation.
• Visible flags for everything else. If the analysis draws on an authority outside the bank, it is marked for verification — a name and year, never a fabricated law report reference, and never presented as checked.

In our validation testing across contracts, full court judgments and legislation, this design produced zero fabricated citations. Not because the underlying model is incapable of inventing one — but because the system is built so that invented citations have nowhere to hide.

The honest limit

None of this makes an AI report legal advice. It makes it something more modest and more useful: a preliminary analysis you can actually check — every citation either verified or visibly flagged. That checkability is the entire difference between decision support and a confident guess.

Check your document before you sign it. Legal Case Analyst reads contracts, leases, judgments and legislation under the law of your specific jurisdiction and returns severity-ranked issues with verifiable citations — as a Word/PDF report within 24 hours. Founding reports are £12 (normally £24) for the first 100 customers.

This article is general information, not legal advice. No solicitor/attorney–client relationship is created by reading it. For advice on your situation, consult a licensed practitioner in your jurisdiction.