A fabricated legal citation is a case reference that does not exist, or that says something the real decision never said. When one makes it into a brief and then into a court's ruling, the consequences are serious: the ruling can be reversed on appeal, and the attorney who filed the fake authority can be sanctioned and reported to the State Bar. California courts now treat both outcomes as live risks, driven in part by the rise of generative AI tools that invent citations with total confidence.
TL;DR
- A fabricated citation is a nonexistent case, or a real case quoted for something it never held. Either can undermine a ruling.
- In 2026, California's Fifth Appellate District reversed a trial court order that relied on a fake citation, finding the error was an abuse of discretion. Wanger Jones Helsley PC represented the prevailing party.
- In 2025, California's first published opinion on AI-hallucinated citations sanctioned an attorney $10,000 after 21 of 23 quotes in his brief turned out to be fabricated.
- Every attorney who signs a brief must personally read and verify each authority in it. That duty does not change because a tool wrote the draft.
- Opposing parties who catch a fake citation should flag it to the court in writing, promptly and specifically.
What is a fabricated legal citation?
A fabricated legal citation is a reference to a court decision, statute, or other authority that either does not exist or does not say what the citing party claims. The two forms matter equally:
- Nonexistent authority: a citation to a case that was never decided. This is the obvious version.
- Misquoted real authority: a genuine case paired with a quotation or holding it never contained. This is subtler and more common, which is why verification means reading the decision, not just confirming the case name resolves.
Fabricated citations reach courts through more than one path:
- Careless copying or misremembered holdings.
- Generative AI tools that produce fluent, authoritative-looking citations that are simply made up, a failure mode the industry calls a hallucination.
The source of the error does not change the legal consequence. A court that rests a decision on authority that does not exist has relied on nothing, and an attorney who presents that authority has put unverified material before the court.
The stakes are highest when the fabrication is not caught before a ruling issues. At that point the error is baked into an order that affects real parties, and correcting it usually requires an appeal.
How can a fabricated citation get a ruling reversed?
A ruling can be reversed when a court's decision rests on authority that does not exist, because relying on a nonexistent case is an abuse of discretion. That is precisely what happened in a 2026 child protective order matter decided by California's Fifth Appellate District, where Wanger Jones Helsley PC represented the prevailing party on appeal.
Here is how the error unfolded:
- A mother sought a protective order for her young son.
- In his closing brief, the father's counsel cited a nonexistent 2005 decision to argue the conduct did not meet the legal standard for abuse.
- The client's team spotted the fabricated authority and alerted the court before any ruling issued.
- The trial court nonetheless entered an order against the mother that repeated the fake citation, appearing to copy it directly from the father's filing. H.C. v. Contreras, No. F089316 (Cal. Ct. App. 5th Dist. May 28, 2026)
On appeal, the Fifth Appellate District reversed. Quoting an earlier California decision, the court explained that the error "seriously undermines the integrity of the outcome and erodes public confidence in our judicial system," and concluded that "the court's ruling is without doubt an abuse of discretion." It assigned the matter to a new trial judge and separately found that the lower court had misstated the law governing abuse, wrongly suggesting the standard required more than the law actually demands. H.C. v. Contreras, No. F089316 (Cal. Ct. App. 5th Dist. May 28, 2026)
One practical note on that decision: it is an unpublished opinion, so under California Rules of Court, rule 8.1115 it generally cannot be cited as precedent in other cases. Its value here is as a concrete illustration of how a fabricated citation, left uncorrected, can travel from a losing brief into a court order and then into a reversal.
Do California lawyers get sanctioned for AI-generated fake citations?
Yes. In September 2025, the California Court of Appeal issued the state's first published opinion addressing AI-fabricated citations and sanctioned the responsible attorney $10,000. The case, Noland v. Land of the Free, L.P., involved an appellate brief in which 21 of 23 case quotations were fabrications, which counsel acknowledged resulted from his reliance on generative AI sources including ChatGPT, Claude, Gemini, and Grok. Noland v. Land of the Free, L.P., 114 Cal.App.5th 426 (2025)
The court imposed several consequences that show how far the fallout reaches:
- A $10,000 monetary sanction on the responsible attorney.
- A ruling that the appeal was frivolous because it rested on negligible legal foundation and was peppered with fabricated citations, violating the fundamental duty attorneys owe to read the authorities they cite.
- A finding that the briefing failed to support its points with citations to real authority, in violation of California Rules of Court, rule 8.204(a)(1)(B).
- An order directing counsel to serve the opinion on his own client, and a referral to the State Bar. Noland v. Land of the Free, L.P., 114 Cal.App.5th 426 (2025)
The court published the decision as an explicit warning to the bar, noting that no California court had previously addressed AI-generated fake authority. It wrote that no brief, pleading, motion, or other paper filed in any court should contain any citation, whether provided by generative AI or any other source, that the responsible attorney has not personally read and verified. That single sentence is the clearest statement of the standard California lawyers are now held to. Noland v. Land of the Free, L.P., 114 Cal.App.5th 426 (2025)
Where did the AI citation problem start?
The defining case came out of federal court in 2023, when a New York judge sanctioned two attorneys and their law firm $5,000 for submitting a brief full of ChatGPT-invented decisions. In Mata v. Avianca, Inc., the lawyers cited cases like "Varghese v. China Southern Airlines" that did not exist, then doubled down by filing purported copies of the fake opinions after the tool assured them the cases were real and available on Westlaw and LexisNexis. Mata v. Avianca, Inc., 678 F.Supp.3d 443 (S.D.N.Y. 2023)
Judge P. Kevin Castel found the attorneys had acted with subjective bad faith sufficient for sanctions under Federal Rule of Civil Procedure 11, and ordered them to send letters to each real judge who had been falsely named as the author of a fabricated opinion. The case became the reference point for every AI-citation ethics advisory that followed, and it established the core lesson that later California decisions build on. Mata v. Avianca, Inc., 678 F.Supp.3d 443 (S.D.N.Y. 2023)
The through-line from Mata to Noland to the Fifth District's 2026 reversal is consistent. Courts do not accept "the AI wrote it" as an excuse, because the duty runs to the human who signed the filing.
How do these cases compare?
The table below summarizes the three leading decisions on fabricated and AI-hallucinated citations that California practitioners should know.
| Case | Court and year | What happened | Outcome |
|---|---|---|---|
| Mata v. Avianca | S.D.N.Y., 2023 | ChatGPT invented multiple fake cases in a brief | $5,000 sanction under Rule 11 |
| Noland v. Land of the Free | Cal. Ct. App., 2025 | 21 of 23 quotes in appellate brief were AI-fabricated | $10,000 sanction; State Bar referral |
| H.C. v. Contreras | Cal. Ct. App. 5th Dist., 2026 | Trial court order relied on a fabricated citation | Order reversed; new judge assigned |
Read together, the three cases show two distinct consequences of the same problem. The lawyer who files a fabricated citation faces sanctions and bar referral. The party who loses because a court relied on one faces the cost and delay of an appeal to undo the damage.
What is a lawyer's duty to verify citations in California?
California lawyers have an affirmative duty of candor toward the court, and a fabricated citation cuts directly against it. Rule 3.3 of the California Rules of Professional Conduct prohibits an attorney from knowingly making a false statement of law to a tribunal and from knowingly misquoting the language of a decision, statute, or other authority. California Rules of Professional Conduct, Rule 3.3
Rule 3.3 turns on knowledge, and courts have noted that a lawyer's knowledge may be inferred from the circumstances. An attorney who files AI-generated citations without reading them is not off the hook simply because the fabrication was the machine's; the Noland court described reading the authorities you cite as a fundamental duty attorneys owe to the court and their clients. The practical standard that emerges from these decisions is straightforward and worth stating plainly:
- Every authority cited in a filing must be independently read and verified by the attorney who signs it.
- Verification means opening the actual decision and confirming both that it exists and that it says what the brief claims.
- Confirming a case name or citation resolves in a database is not enough; the quotation and holding must match.
- Generative AI can assist with drafting, but it cannot be the last set of eyes on a citation.
- The duty applies to every paper filed, from a routine motion to an appellate brief.
That diligence is not a formality. In the Fifth District matter, catching the fabricated authority protected the interests of a child and preserved the integrity of the proceeding, even though the trial court initially repeated the error.
What should you do if opposing counsel cites a fake case?
If you believe opposing counsel has cited a nonexistent or misquoted case, bring it to the court's attention promptly, specifically, and in writing. Acting before the court rules is critical, because a fabricated citation is far easier to keep out of an order than to remove from one on appeal.
Take these steps:
- Verify the citation against an official source, such as the California Courts website or a recognized reporter.
- Identify the specific problem in writing, for example that the reporter citation does not resolve or that the quoted language does not appear in the actual decision.
- Attach or reference the real authority where one exists.
- Raise it before the court rules, so the trial court can correct course and the issue is preserved for any appeal.
Timing shaped the outcome in the Fifth District case. The prevailing party's team flagged the fabricated authority before any ruling issued, which built the record that later supported reversal even though the trial court initially repeated the fake citation.
For parties without counsel, the same principle applies in plain terms. If a case someone cites cannot be found in an official source such as the California Courts website or a recognized reporter, that is worth raising with the court rather than assuming the citation is simply obscure.
FAQ
What is a fabricated legal citation?
A fabricated legal citation is a reference to a case, statute, or other authority that does not exist, or a real authority quoted for something it never actually said. Both forms mislead the court. They increasingly originate from generative AI tools that invent realistic but false citations, a failure known as a hallucination.
Can a ruling be overturned because of a fake citation?
Yes. A California appellate court can reverse a ruling that relied on a nonexistent case, because resting a decision on authority that does not exist is an abuse of discretion. In 2026, the Fifth Appellate District reversed a trial court order for exactly that reason and assigned the matter to a new judge.
Do California lawyers get sanctioned for AI-hallucinated citations?
Yes. In 2025, California's first published opinion on the issue sanctioned an attorney $10,000 after 21 of 23 case quotations in his appellate brief proved to be AI-fabricated. The court also referred the matter to the State Bar, showing that consequences extend beyond a monetary fine.
Whose job is it to verify a citation?
The attorney who signs and files the document. California courts have made clear that no filing should contain any citation, from AI or any other source, that the responsible attorney has not personally read and verified. Delegating a draft to a tool does not transfer that duty away from the lawyer.
Does using ChatGPT to write a brief break ethics rules?
Using AI to assist with drafting is not itself a violation. Filing AI-generated citations without independently verifying them can violate the duties of candor and competence under the California Rules of Professional Conduct. The rule is about verification, not about whether a tool was used.
What should I do if the other side cites a nonexistent case?
Verify it against an official source, then notify the court promptly and in writing, identifying the citation and explaining what your check found. Attach the real authority if one exists. Raising it before the court rules is far more effective than challenging a fabricated citation after it appears in an order.
The bottom line
Fabricated citations, whether the product of AI hallucination or old-fashioned error, carry two hard consequences in California: reversal for the party that relied on one and sanctions for the lawyer who filed it. The defense against both is the same discipline courts have repeatedly demanded, which is that a human attorney read and verify every authority before it reaches a judge.
The Fifth Appellate District's 2026 reversal shows the other half of that equation, which is that catching a fabricated citation early, and putting the objection on the record, can be what protects a client and preserves a fair result.
Wanger Jones Helsley PC represented the prevailing party in H.C. v. Contreras. Counsel of record on the appeal were Amanda G. Hebesha, John P. Kinsey, and Stephanie Hosman.