Phantom Citations in Real Courts: What NJ RPC 3.3 Requires When Your AI Hallucinates a Case

The case name looked real. The citation looked real. The quoted holding — perfectly tailored to your argument — looked very real. It wasn't.

If you've used ChatGPT, Copilot, or any generative AI tool to assist with legal research, you are operating in an environment where this scenario is not hypothetical. It has happened to experienced attorneys in federal court, state court, and, increasingly, to practitioners who should have known better after the warnings became public. The question for New Jersey lawyers is no longer whether AI can hallucinate a citation — it's what your professional obligations are when one makes it into a filing.

The answer lives squarely in RPC 3.3.

What Mata v. Avianca Actually Established (And What Came After)

In June 2023, U.S. District Judge P. Kevin Castel of the Southern District of New York sanctioned attorneys Roberto Mata and Steven Schwartz — along with their firm — after a ChatGPT-generated brief cited no fewer than six nonexistent cases. The court found violations of Rule 11 and imposed $5,000 in sanctions. The opinion was surgical in its rebuke: the attorneys had not only submitted fabricated citations but had affirmed their existence after opposing counsel flagged them.

Mata wasn't an outlier. It was a starting gun.

Since that ruling, courts across the country have moved from curiosity to active scrutiny. In Gauthier v. Goodyear Tire & Rubber Co. (E.D. Tex. 2023), a plaintiff's attorney was sanctioned after submitting AI-generated citations that didn't exist. In Park v. Kim (2d Cir. 2024), the Second Circuit took the rare step of referring an attorney to its grievance panel after fabricated citations appeared in an appellate brief — escalating the consequences from financial penalty to potential disciplinary referral. Closer to home, the District of New Jersey has not issued a landmark AI-sanctions ruling as of this writing, but it has adopted standing orders in several courtrooms requiring AI disclosure, a clear signal that the bench is watching.

The trajectory is unmistakable: what began as sanctions under procedural rules is migrating toward professional discipline.

RPC 3.3 Is Not Just About Lying. It's About Knowing.

New Jersey's RPC 3.3(a)(1) prohibits a lawyer from making "a false statement of fact or law to a tribunal." RPC 3.3(a)(3) goes further, prohibiting the offering of evidence the lawyer "knows to be false." But the provision that catches most attorneys off guard is the ongoing duty: under RPC 3.3(b), if you discover that you've made a false statement of material fact or law to a tribunal, you are required to take "reasonable remedial measures," up to and including disclosure to the court — even if doing so requires revealing information that would otherwise be confidential under RPC 1.6.

Read that again. The candor obligation can override confidentiality.

This means the moment you discover a cited case doesn't exist — whether opposing counsel flags it, the court asks about it, or your own associate catches it during a subsequent review — your ethical obligation crystallizes. You don't get to quietly amend without disclosure. You don't get to hope no one noticed. RPC 3.3 requires you to act.

A 3-Step Pre-Filing Verification Protocol

The only reliable defense is prevention. Here is a concrete, repeatable workflow that every NJ solo and small firm attorney should implement before any AI-assisted research reaches a filing:

Step 1 — Source, Don't Trust. When AI surfaces a case citation, treat it as a lead, not a source. Your first move is to locate the actual case in Westlaw, Lexis, or Fastcase. If you cannot find the case in a paid, authenticated legal database, it does not go in the brief. Period. Do not Google it. Do not ask the AI to confirm it. Search the primary database.

Step 2 — Verify the Quoted Language. Finding that a case exists is not enough. AI tools routinely fabricate or misattribute quoted language even from real opinions. Pull the actual opinion. Locate the specific page and paragraph. Confirm that the holding or language you intend to cite appears exactly where the AI claimed it does. Pincite it yourself.

Step 3 — Log the Verification. Create a simple citation verification log for every brief — a running document noting each citation, the database used to confirm it, the date verified, and the attorney's initials. This takes under ten minutes for a typical motion brief and creates a defensible record if a judge or bar investigator ever asks whether you checked. In a post-Mata world, "I trusted the AI" is not a defense. A log is.

When Self-Reporting Becomes Required

This is the question attorneys most want to avoid, and the one RPC 3.3 answers most directly.

If you discover a fabricated citation before filing, the answer is simple: remove it, correct your research, and move on. No disclosure required.

If you discover it after filing but before the proceeding concludes, RPC 3.3(b) is triggered. You must take remedial measures, which at minimum means correcting the record with the tribunal. That likely means filing a corrective submission and notifying opposing counsel. Depending on how materially the false citation affected any ruling or the opposing party's litigation posture, more may be required.

If you discover it after the matter has concluded, the analysis becomes more nuanced and fact-specific. At that point, consult with ethics counsel before taking any unilateral action — the ACPE hotline (the NJ Advisory Committee on Professional Ethics) exists precisely for situations like this.

One critical nuance: the duty under RPC 3.3 applies regardless of intent. You don't have to have known the case was fake when you filed it. The obligation attaches upon discovery.

The Bottom Line for NJ Practitioners

Judges in New Jersey and across the federal bench have made clear they view phantom citations as a serious breach — not a forgivable tech glitch. The sanctions record since Mata shows a consistent willingness to impose financial penalties, require corrective filings, and, in escalating cases, refer matters to state bar grievance committees.

RPC 3.3 is your candor obligation. It predates AI by decades. But AI has created a new and highly efficient way to violate it — and the professional consequences are real.

Build the verification protocol. Run it on every filing. And if something slips through, act immediately. The cover-up — the silence, the delay, the hope that no one checks — is always worse than the error.