The Fifth Circuit Cited the Wrong Rule: What Citation Checking Has to Catch

In June 2024 the U.S. Court of Appeals for the Fifth Circuit declined to adopt a special rule on generative AI in briefs. It reminded counsel that filings “shall be carefully checked for truthfulness and accuracy as the rules already require,” and closed with a line that has been quoted ever since: “‘I used AI’ will not be an excuse for an otherwise sanctionable offense.”

The notice pointed lawyers to their duties under Federal Rule of Appellate Procedure 6(b)(1)(B). That rule tells you how to read a form reference in bankruptcy appeals. The provision the court meant is Rule 46(b)(1)(B), which allows suspension or disbarment of an attorney who “is guilty of conduct unbecoming a member of the court’s bar.” One missing digit moved the citation from attorney discipline to bankruptcy procedure.

The error was reported on September 22, 2026 by The National Law Review, in a piece by Oliver Roberts crediting Utsav Gupta, a Stanford master’s candidate, with spotting it. The article reported that the notice was still uncorrected more than two years later. That has since changed: the notice now served at the court’s own link cites Rule 46(b)(1)(B), and the file’s metadata shows it was regenerated on the morning of September 24, 2026. There is no correction note on the page.

We think this small episode says more about citation checking than most sanctions orders do.

It was not an AI failure

Nothing suggests AI produced the wrong citation. The National Law Review itself calls it most likely a typographical slip. That is the point: a wrong authority in a filing is the drafter’s problem regardless of how the draft was produced. The court said exactly that about lawyers. It applies to everyone who writes for a court.

The citation would have passed an existence check

Much of the conversation about “hallucinated” citations is about authorities that do not exist. Those are the easy ones. A case that is not in any database, or a reporter page that points nowhere, fails the first lookup.

Rule 6(b)(1)(B) exists. Any check that asks “is this a real rule?” returns yes. What failed was the second question: does this authority say what the sentence claims it says? That question cannot be answered by confirming a citation resolves. Someone has to read the provision against the proposition.

This is the gap that matters most in practice. Fabricated authorities are embarrassing and increasingly easy to catch. Real authorities attached to the wrong proposition are harder to catch, and they are the ones that survive review.

Errors travel through secondary sources

The wrong citation did not stay on the court’s website. Commentary published in June 2024 repeated it. The e-Discovery Team blog quoted the notice with Rule 6(b)(1)(B), and The National Law Review reports that it also appeared in law-firm commentary and in a judge’s discussion of lawyers’ duties.

Each of those writers quoted the court accurately. That is exactly why the error spread: a faithful quotation of a flawed source carries the flaw forward. Anyone who cited the commentary instead of reading Rule 46 inherited it.

The correction teaches the second half of the lesson. Primary sources change, sometimes silently. A citation checked against the notice on September 23 and one checked on September 24 would produce different results, and nothing on the document tells a reader which version they are looking at.

The standard is being enforced anyway

None of this softens the duty. In Fletcher v. Experian Information Solutions, Inc., No. 25-20086, decided February 18, 2026, the same court sanctioned an attorney $2,500 for a reply brief containing fabricated citations and for evasive answers when asked about them. The sanction rested on Rule 46(c) and the court’s inherent authority, and the opinion cites Rule 46(b)(1)(B) correctly. The lack of candor was part of what the court sanctioned, not an afterthought to it.

What a citation check actually has to cover

For firms building a verification step into their workflow, the episode suggests a sequence rather than a single test:

• Existence. Does the authority exist, and does the citation resolve to it?
• Support. Does the pinpoint actually say what the sentence claims? This requires reading, not lookup.
• Rules and statutes, not only cases. Most checking habits and many tools are built around case law. Procedural rules are cited constantly and checked far less often.
• Primary over secondary. Quote the court, the rule or the statute, not an article about them, however reliable the article.
• Version and date. Note when you checked a source that can change. Court websites are updated without notice.
• Candor when something is wrong. Correct it promptly and plainly. Fletcher shows that the response to an error can cost more than the error.

Where Lawnova fits

We build drafting tools for appellate practice, so we are careful about what we claim. COAPP, our Colorado appellate brief tool, grounds record citations in the documents you upload and audits case citations against the CourtListener database before export, marking each one “verified, ambiguous or not found, so no unverified authority reaches a filing unnoticed.”

That is an existence-and-record check. It is not a substitute for the support question above, and we do not describe it as one. Its job is to make the remaining human review smaller and more precise: to show a lawyer exactly which citations still need eyes, rather than to promise that none do.

If your firm is deciding what to disclose about AI use, our note on certificate of AI use language covers the drafting side. For how courts are shifting from asking whether AI was used to asking whether anyone checked, see our earlier analysis.

Source: Oliver Roberts, “The Fifth Circuit Warned Lawyers to Verify Citations, Then Cited the Wrong Rule Itself,” The National Law Review, September 22, 2026. Rule text from the Federal Rules of Appellate Procedure; court notice checked on September 24, 2026.