That’s the lesson of Quinteros v. Harbor Distributing, LLC (Cal. Ct. App., 1st Dist., June 11, 2026), where the First District affirmed sanctions against a law firm and three of its attorneys after a brief filed under their names turned out to be built on citations to cases that don’t exist and quotations nobody ever wrote. The firm’s defense was that an outside contract attorney did the drafting and apparently used AI to do it. The court wasn’t moved.

How a Routine Motion Became the Worst Misconduct the Judge Had Ever Seen

The underlying dispute was ordinary. The Lipeles Law Group filed a wage-and-hour class action in Los Angeles, then filed a nearly identical one in San Francisco against the same defendants six months later. The defense moved to stay the second as a duplicate. That’s a routine request. The firm opposed it, and that’s where everything came apart.

The trial court found the brief contained two case citations that were entirely fabricated, meaning the cases simply do not exist, plus no fewer than eight quotations falsely attributed to real cases. The judge called it the worst attorney misconduct he had seen from the bench. He sanctioned the firm and its three attorneys $6,000, jointly and severally, meaning each is on the hook for the full amount, and flagged the matter for the State Bar.

When confronted, the firm pointed at its contract attorney, who had signed a declaration swearing he used a legitimate research tool, ran a citation check three times, and never touched AI. The lawyers whose names were on the brief said they trusted him. Two admitted they never read it before it went out.

Generative AI Doesn’t Change Who Answers for It

On appeal, the firm raised three arguments and lost all three, though not all the same way. Two of them, the procedural timing complaint and the objection to paying the other side, the court wouldn’t even reach, on forfeiture, the rule that you can’t raise on appeal an objection you didn’t make in the trial court first. The firm never invoked the statute’s 21-day safe harbor, a window to withdraw a bad filing and avoid sanctions, while it was before the trial judge. It buried its central request in a footnote. It even stipulated to the tentative ruling it later attacked. The third argument, that the conduct didn’t merit sanctions, the court did reach, and rejected on the merits as within the trial judge’s discretion.

The part that matters for everyone else is what the court said about responsibility. Drawing on a fast-growing line of California decisions about AI-fabricated authority, the panel held that the duty to verify every citation cannot be handed off to any technology, or to any other person. The lawyers’ names were on the brief. One of them signed it. That signature certifies that the contents are warranted by existing law, and you don’t get to walk it back because a contractor or a chatbot did the typing.

Why This Matters Beyond the Courtroom

The holding is about lawyers, but the principle reaches any business that uses AI or outside vendors. If your team uses AI to draft a contract, a compliance filing, or a regulatory submission, accountability for the result sits with the human who releases it. The fluent, confident, fabricated output is the dangerous one, because it reads as authoritative right up until somebody checks.

For in-house counsel and executives who supervise outside firms and vendors, the case is a prompt to ask one question. Who actually reads the work before it carries our name? “We trusted the vendor” lost here, and it loses anywhere the buck is supposed to stop with you.

For anyone wiring AI into a workflow, the rule is simple. A human who understands the subject reviews the output before it goes anywhere, every time. The speed is real. So is the exposure when nobody checks.

The Bottom Line

AI is now part of how work gets produced, and courts have stopped treating “the AI did it” as an excuse. Quinteros confirms that delegation, whether to a contractor or to a machine, doesn’t move responsibility off the person whose name is on the result. The businesses that get hurt by this won’t be the ones that banned the tools. They’ll be the ones that used them without deciding, in advance, who reads the output and signs off. That decision is far cheaper as a policy than as a sanction. Horst Legal Counsel advises businesses on AI governance, professional responsibility, and litigation risk. If you want to pressure-test how AI-assisted work moves through your organization before it becomes a problem, we’re glad to talk it through.

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Horst Legal Counsel | March 2026

If you have been following California’s growing body of appellate authority on AI-generated legal citations, you have watched the courts build a wall, one published opinion at a time.

• First came the warnings to attorneys.

• Then came the sanctions.

• Then, in Torres Campos v. Munoz, the consequences reached the bench itself when fabricated case law made it into a signed court order.

Now the First District Court of Appeal has laid another brick. In Sheerer v. Panas (2026) ___ Cal.App.5th ___ (A171804), the court extended the prohibition against unverified AI-generated citations to self-represented litigants, and it made clear that the available penalties go well beyond striking a deficient brief.

The message is no longer limited to the bar. It applies to everyone who files a document in a California court.

What happened

The underlying dispute was a family law matter involving child support. Anna Sheerer appealed a trial court order that failed to account for her ex-husband Thomas Panas’s bonus and restricted stock unit compensation when calculating support. The Department of Child Support Services agreed with Sheerer that the trial court had erred. On the merits, the Court of Appeal reversed. That part of the opinion is unpublished.

What the court chose to publish was something else entirely.

In his respondent’s brief, Panas:

• Cited at least two cases that do not exist.

• Fabricated quotations that appear nowhere in the real cases he did cite.

• Referenced hearings in the proceedings below that the appellate court could not locate in the record.

When Sheerer moved to strike the brief, Panas filed a declaration explaining that his “error” resulted from using a generative AI tool without verifying the output. The court was not persuaded by his framing.

The court’s reasoning

The First District began where you would expect: with the principle that self-represented litigants are held to the same standards as attorneys. Citing Kobayashi v. Superior Court and Keitel v. Heubel, the court rejected the notion that pro se status provides any shelter from the obligations that attach to every filing.

As our Supreme Court put it more than three decades ago, a doctrine permitting exceptional treatment for self-represented parties “would lead to a quagmire in the trial courts, and would be unfair to the other parties to litigation.”

The court then situated Panas’s conduct within the line of authority developing since generative AI tools became widely available:

1. Noland v. Land of the Free, L.P.: The Second District decision warning attorneys about unverified AI citations.

2. People v. Alvarez: Holding that honesty in court filings is paramount.

The opinion includes a passage that captures the court’s concern precisely: The rule of law depends on courts impartially applying law to facts. That foundation is threatened when litigants falsify the truth, “especially when done by using technological innovations that can spin persuasive webs of untruths and invent legal principles or authorities.”

Consequences and Penalties

Having disregarded Panas’s brief in its entirety, the court turned to consequences. It noted that under California Rules of Court, rule 8.276(a)(4), the court may impose monetary sanctions on its own motion for unreasonable violations. While the court declined to impose sanctions here due to the interests of the children involved, it published the warning as a deterrent.

Why this matters beyond family court

Sheerer v. Panas is a narrow case on its facts, but the published portion carries broad implications. Three things stand out:

• Universal Obligations: The court closed the gap. Sheerer makes explicit that the same obligations apply to every litigant, represented or not.

• Escalating Consequences: The court has put all parties on notice that monetary sanctions are available for AI-related citation failures. Future litigants should not expect the same restraint shown to Panas.

• No “Ignorance” Defense: The court’s response to Panas’s claim that he didn’t “knowingly” submit false info was direct: his lack of knowledge resulted from a failure to verify. The duty is to confirm every citation exists and says what you claim it says.

What businesses and individuals should take away

If your company uses AI tools in any part of a legal workflow—whether for research, drafting, or document review—Sheerer v. Panas adds to the growing authority that verification is not optional.

Key Takeaway: The obligation runs to the person whose name is on the filing, regardless of whether that person is an attorney, a corporate representative, or a self-represented individual.

• For Litigants: If you suspect an opposing party is submitting AI-generated work product without verification, you now have clear authority to seek relief.

• For Self-Represented Parties: Understand that the tools you use do not change the standard you are held to. The consequences are getting sharper.

Bottom Line

Sheerer v. Panas confirms what the California appellate courts have been building toward for the past two years: The duty to verify every citation in every court filing is universal. Horst Legal Counsel tracks AI-related litigation developments as part of its commitment to responsible AI integration in legal practice. For questions about how these decisions affect your business or your case, contact Jason Horst at jason@horstcounsel.com.

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