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Kertesz v. Colony Tire Corp. et al.

U.S. District Court, District of New Jersey · D.N.J. · New Jersey bar guidance

Court sanction

Verified May 14, 2026

Citation
Kertesz v. Colony Tire Corp., No. 20-12364, 2025 WL 2779094 (D.N.J. Sept. 30, 2025) (Semper, J.)
Decided
September 30, 2025

Summary

Counsel for a party in this matter conceded that erroneous citations and fabricated quotations appearing across multiple briefs resulted from the attorney's use of a generative AI tool, the specific name of which was not disclosed in the order. The court declined to impose monetary sanctions but issued a formal warning, noting that uncritical reliance on generative AI may run afoul of the New Jersey Rules of Professional Conduct. The court further refused to consider the attorney's amended briefs and treated propositions unsupported by genuine authority accordingly.

AI tool:
Unspecified generative AI
This case summary is informational only. Verify the underlying opinion or order against the primary source before relying on it in any filing or client matter.

What sanction did the court impose?

Warning issued in lieu of monetary sanctions. The court declined to consider amended briefs submitted to cure the defective citations and treated unsupported propositions as unsupported on the merits. No suspension, fee award, or bar referral was ordered.

Why does Kertesz v. Colony Tire Corp. et al. matter for law firms using AI?

Kertesz illustrates the lighter end of the federal sanctions spectrum for AI-generated citation errors: a warning rather than a fee award, but with real consequences. The court’s refusal to consider the attorney’s amended briefs meant the underlying propositions were treated as unsupported, which is a substantive litigation loss layered on top of the reputational hit. For a managing partner, the lesson is that “no monetary sanction” is not the same as “no harm.” A court that loses confidence in counsel’s citations may simply stop reading the corrections.

Sources

Primary sources

Further reading

Source PDF is a Westlaw printout mirrored from the Damien Charlotin hallucination database. We are working to add the underlying court docket (PACER, CourtListener, or court website) as a second source.