Law360 (June 12, 2026, 4:32 PM EDT) -- A Connecticut attorney could be sanctioned for including fake case quotes and misrepresentations of the law in court filings that seek dismissal of a trademark case against a taco restaurant, a federal judge said Friday in questioning whether the documents were sullied by artificial intelligence.

U.S. District Judge Vernon D. Oliver ordered Greenwich-based solo practitioner Hilary B. Miller to show cause why he should not be sanctioned and why the two motions at issue, filed in April and May, should not be stricken from the District of Connecticut docket. Judge Oliver identified 16 instances of either erroneous citations, misstatements of the law or quotes that do not exist and wrote that it "appears" Miller used generative AI without verifying the outputs.

"In an adversarial system that depends on litigants to candidly present accurate authority, such hallucinations mislead the court, forcing it either to expend substantial resources verifying fabricated material or, worse, risk reliance on an erroneous statement of the law," the order says.

The judge set a Hartford hearing for June 25.

The lawsuit, filed Feb. 19, accuses two Tacobarn entities in Greenwich and Newtown of infringing on the trademark of Bartaco restaurants, a chain of about 31 Latin-inspired locations.

"Defendant Tacobarn is owned and controlled by David Boyajian, a former senior executive of Bartaco who played a leadership role in Bartaco's early growth and expansion and was intimately familiar with Bartaco's brand, operations, and customer experience," the complaint says. "After leaving Bartaco, Boyajian opened a directly competing restaurant concept using the name 'Tacobarn' — a mark composed of the same two words as Bartaco, merely reversed — and offering identical restaurant and bar services."

The defense moved for dismissal April 21, arguing that Bartaco is seeking "an extraordinary monopoly over the combination of two of the most generic terms in the restaurant lexicon" and noting the difference between the words "bar" and "barn."

The defendants said that the parties' names are not confusingly similar and that Bartaco was asserting a spurious trade dress claim based on each side's use of "paper order slips, rectangular metal trays, napkin canisters, salsa bottles, juice presses, and staff aprons."

On May 21, Tacobarn asked the court to exclude an expert report that the plaintiffs filed in opposition to dismissal, calling it improper extrinsic evidence that the court cannot consider at the pleadings stage.

According to Judge Oliver, apparent hallucinations in the filings include a misstatement of the pleading standard laid out in the U.S. Supreme Court's seminal 2009 opinion in Ashcroft v. Iqbal and incorrect page numbers for cited cases. He also called out a misplaced reliance on the Second Circuit case Streetwise Maps Inc. v. VanDam Inc. to argue a point about incontestability, saying the case "doesn't address incontestability at all," numerous quotes that do not appear in the cited cases, and several arguments based on case law that does not support the defendants' point.

The motion to exclude extrinsic evidence cites the 2002 Second Circuit decision in Chambers v. Time Warner Inc. to argue that the "governing rule is settled."

"On a motion to dismiss under Rule 12(b)(6), the court's review is limited to 'the complaint, any written instrument attached to it as an exhibit, any statements or documents incorporated in it by reference, and any document upon which the complaint heavily relies,'" the motion said, purporting to quote from Chambers.

But Judge Oliver wrote in his order that this quote "does not exist."

The motion also claimed that Chambers allowed a court to take "judicial notice of adjudicative facts" under Federal Rule of Evidence 201(b). The judge's order said the case "does not stand for this proposition."

"Nothing about FRE 201(b) appears in Chambers," the judge wrote.

Federal Rule of Civil Procedure 11(b) "imposes an affirmative duty on parties and counsel to ensure that all papers filed with the court are factually and legally well-founded," according to the order. "These obligations take on particular significance in the context of filings prepared with the assistance of generative artificial intelligence."

On June 2, Judge Oliver participated in a panel discussion of artificial intelligence in the legal industry, held as part of the Connecticut Bar Association's annual conference in Hartford. He cautioned an audience of attorneys to use AI only to "verify what you already know" and admonished them to "read the cases" that appear in AI outputs.

Miller declined to comment to Law360 on Friday. Counsel for the plaintiffs did not immediately respond to requests for comment.

The plaintiffs are represented by Gregory S. Kimmel of Berchem Moses PC and Walter B. Welsh of Welsh IP Law LLC.

The defendants are represented by Hilary B. Miller.

The case is Barteca Intermediate Holdings LLC et al. v. Tacobarn Newtown LLC et al., case number 3:26-cv-00250, in the U.S. District Court for the District of Connecticut.

--Editing by Amy French.

Update: This article has been updated with a response from counsel for the defendants.

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