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U.S. District Court for the Eastern District of Louisiana · E.D. La. · Decided March 5, 2026

Citation:

Woodward Harbor LLC v. City of Mandeville, No. 2:23-cv-05824-BSL-EJD, ECF No. 101 (E.D. La. Feb. 5, 2026) (Long, J.) (dismissal); ECF No. 117 (E.D. La. Mar. 5, 2026) (Long, J.) (Rule 11 sanctions); LSU Health Found. New Orleans v. Jones Fussel L.L.P., No. 2026-02562, Sec. 10 (Civ. Dist. Ct. Orleans Par. filed Mar. 27, 2026) (legal-malpractice action).

AI tool:

Westlaw Precision AI and ChatGPT (per Walker's sworn declaration of February 12, 2026, ECF No. 104-1)

Sanction amount:

$1,000 personal sanction against attorney John R. Walker, plus mandatory 2 hours of Generative AI CLE by December 31, 2026, plus voluntary repayment to clients of fees earned drafting the offending brief. The other three signing attorneys received judicial admonition without monetary sanctions.

What happened

Regulatory-takings dispute over the Mandeville City Council's denial of the proposed Sucette Harbor Project on land owned by LSU Health Foundation New Orleans and leased by Woodward Harbor LLC. In opposition (filed June 3, 2025; ECF No. 97) to the City's second Rule 12(b)(6) motion to dismiss the remaining equal protection claim, plaintiffs' counsel filed a brief drafted by John R. Walker (Jones Fussell LLP) and electronically signed by Walker and Michael R. C. Riess (Riess LeMieux LLC), with Johanna Elizabeth Lambert (Riess LeMieux LLC) and Thomas H. Huval (Jones Fussell LLP) also listed in the signature blocks. The brief contained at least eleven citations to cases that either did not exist or were incorrectly summarized, relied on, or quoted from. Identified fabrications included 'Wood v. City of Utica, 890 F.3d 273 (2d Cir. 2018)' and 'Qutb v. Ramsey, 285 F. App'x 251 (5th Cir. 2008)' (the real Qutb is a D.D.C. district court case at 285 F. Supp. 33). The City flagged the hallucinations in its reply brief; plaintiffs' counsel did not withdraw, file a sur-reply, or correct the errors. Walker, a Louisiana attorney with 43 years of practice and no prior disciplinary history, conceded in a sworn 28 U.S.C. Sec. 1746 declaration (Feb. 12, 2026) that he alone drafted and filed the brief using 'WESTLAW Precision AI and ChatGPT' to assist him, that he was 'new to using these tools and did not appreciate the limitations of and potential pitfalls in using such tools, including the risk that ChatGPT would hallucinate.' He further attested that on June 6, 2025 (the same day the City filed its reply brief flagging the fabrications), he underwent an L4-S1 lumbar fusion surgery and 'failed to note defendant counsel's comments regarding the errors.' Post-incident, Walker read ABA Formal Opinion 512 (July 29, 2024) on generative AI and committed to independently locating and verifying every cited authority going forward.

Outcome

Two orders, by Judge Brandon S. Long. (1) DISMISSAL ORDER (Feb. 5, 2026, ECF No. 101): granted the City's Rule 12(b)(6) motion and DISMISSED Plaintiffs' Section 1983 / equal protection claim and declaratory-relief requests WITH PREJUDICE; the court 'chose to ignore most of Plaintiffs' arguments' because of the hallucinated citations; announced a separate Rule 11 show-cause proceeding. (2) SANCTIONS ORDER (Mar. 5, 2026, ECF No. 117), following a Feb. 24, 2026 show-cause hearing: (a) Walker SANCTIONED PERSONALLY $1,000, payable to the Clerk by March 10, 2026; (b) Walker ORDERED to attend 2 hours of CLE on Generative AI by December 31, 2026 and file proof; (c) the court recognized that Walker had agreed to REPAY HIS CLIENTS the fees he earned drafting the opposition brief; (d) the three other signing attorneys (Riess, Lambert, and Huval) were NOT sanctioned, the court accepting their representations that Walker alone drafted the brief, that they were unaware of his AI use, and relied on his case citations; (e) the court commended the Plaintiffs' law firms for adopting AI procedures, mandatory cocounsel practices, and AI-misuse training going forward. Riess and Lambert retained Baker, Donelson, Bearman, Caldwell & Berkowitz to prepare their show-cause response. (3) On March 27, 2026, LSU Health Foundation New Orleans filed a legal-malpractice petition in Civil District Court for Orleans Parish (No. 2026-02562) against Jones Fussell LLP, Riess LeMieux LLC, Michael Riess, Johanna Lambert, and John Walker, alleging the hallucinated brief and the failure to correct it caused dismissal of the underlying claims and exposure to potential Section 1988 fee-shifting.

The Woodward Harbor / LSU Health matter is the Eastern District of Louisiana’s most prominent generative-AI hallucinations decision to date and a clean illustration of the now-standard two-stage federal AI sanctions sequence: (1) a merits order that “ignores” the affected arguments, decides the underlying motion on the surviving record, and dismisses the claim; followed by (2) a separate Rule 11 show-cause proceeding and sanctions order against counsel personally. Judge Long’s two orders (Feb. 5 and Mar. 5, 2026) are notable for three doctrinal points.

First, the court treated counsel’s failure to read and correct the City’s reply brief, which had expressly flagged the fabricated citations, as an independent aggravating factor. The order observes that “Plaintiffs took no action in response to the reply brief: they did not withdraw their opposition, file a surreply, or otherwise contend with Defendant’s claim that they had cited fake authorities.”

Second, the sanctions order is among the first in the Fifth Circuit to address how Rule 11 applies to multi-firm cosigners on an AI-drafted brief. The court accepted Walker’s sworn admission that he alone drafted the brief and that the other three attorneys (Riess, Lambert, Huval) had no knowledge of the AI use, but explicitly cautioned that “when delegating brief-drafting responsibility to a cocounsel, the attorneys must still comply with Rule 11 when they act as cosigners.” Citing Pavelic & LeFlore v. Marvel Entertainment Group, the court underscored that signing creates “personal, nondelegable responsibility.” It declined to sanction the three cosigners under the “least severe sanction adequate” principle, but commended the firms for adopting AI procedures, cocounsel practices, and AI-misuse training in response to the show cause.

Third, the downstream legal-malpractice petition filed March 27, 2026 by LSU Health Foundation New Orleans in Civil District Court for Orleans Parish, against Jones Fussell LLP, Riess LeMieux LLC, Michael Riess, Johanna Lambert, and John Walker, is a notable development: it is one of the first publicly filed legal-malpractice actions in the United States in which a former client sues its lawyers in solido for the consequences of an AI-hallucinated brief, framing the misconduct under Louisiana Rule of Professional Conduct 1.1 (competence). The malpractice petition specifically pleads that even cosigning attorneys who claimed not to have read the City’s reply brief still billed for their time reviewing it. For firms, the case illustrates how the malpractice exposure from unverified AI use can survive the dismissal of the underlying federal action and migrate into a state-court professional-liability claim that includes both the drafting attorney and the signing co-counsel.

Primary sources

• https://www.courtlistener.com/docket/68152489/woodward-harbor-llc-v-city-of-mandeville/

Last verified: April 24, 2026. Verify against primary sources before relying on this in a filing.