Quick check
Guess first, no penalty. In a 2025 English High Court case, 18 of 45 citations in one set of papers didn't exist. Who did the court say has to check AI legal research?
A citation is the reference that tells a reader where to find a case. AI tools can produce citations to cases that were never decided, with names, courts and quotes that look real.
In Mata v. Avianca (US District Court, Southern District of New York, 22 June 2023), lawyers "submitted non-existent judicial opinions with fake quotes and citations created by the artificial intelligence tool ChatGPT". The court imposed a $5,000 penalty and said there is "nothing inherently improper" about using a reliable AI tool, but lawyers have "a gatekeeping role" to ensure accuracy (opinion).
In England, the Divisional Court in Ayinde v London Borough of Haringey [2025] EWHC 1383 (Admin) said users have "a professional duty" to check AI research "by reference to authoritative sources" (judgment).
Open every case yourself
So before a brief (a written argument for the court) goes out, open every cited case in an official or trusted source. If you can't find it, treat it as not existing. Never ask the AI to confirm its own citations.
Citation check, draft brief v2:
1. Smith v Jones [citation]: found on the court's site. Pin cite checked.
2. Varghese v China Southern [citation]: not found in any database.
Flagged to the lawyer.
3. [case 3]: found. Quote not in the opinion. Flagged.Fill the gaps
Fill the gaps in the same check.
Check
2. Varghese v China Southern: 3. [case 3]: found.
Try it
Your steps, about 2 minutes
- 1.Add line 4 to your check sheet: "Open every cited case in a trusted source. Not found means not real." Then check two citations from any AI research answer.2 min