Amarsingh v. Frontier Airlines: 10th Circuit sanctions attorney $1,000 for ChatGPT-fabricated citations

The problem

Attorneys are increasingly filing court briefs whose case citations were produced by generative-AI tools and never verified. When those tools “hallucinate,” they generate citations that look real, properly formatted and plausible, but refer to cases that do not exist. In Amarsingh v. Frontier Airlines, Inc., the Tenth Circuit’s review of the appellant’s opening brief “revealed serious flaws, including citations to nonexistent cases and attribution of propositions or quotations to two real cases that did not stand for the propositions or contain the quotations” (source [1]).

What was built

Kusmin L. Amarsingh, an attorney representing herself, used a generative-AI tool to research and draft her appeal (source [1]). After the court ordered her to correct the citations or explain them, she admitted she “had used ChatGPT, which generated the seven fabricated case citations,” and that she had not verified them (source [3]; the same admission, “which generated the seven fabricated case citations,” appears in the source [1]). Colorado Politics likewise reported the brief rested on “unverified ChatGPT” citations (source [2]). The panel held that it would “also impose sanctions on Amarsingh for her misuse of generative artificial intelligence in researching and drafting her appellate brief” (source [1]).

The outcome

In an unpublished Order and Judgment filed February 9, 2026, the Tenth Circuit affirmed the dismissal of Amarsingh’s claims and, electing “to proceed under Rule 38,” concluded “this appeal is, in part, frivolous as argued” and that her failings were “quite serious and warrant a significant sanction” (source [1]). The court ordered that “Amarsingh must pay $1,000 to Frontier to offset attorney fees and costs Frontier incurred in responding to the problems” in her brief, within 30 days and with a sworn certification of compliance (source [1]). As a second sanction, the court directed the Clerk’s Office to transmit the order “to the appropriate attorney-disciplinary authority of the State of Maryland,” where she is licensed (source [1]). Colorado Politics reported the court ordered the lawyer to “pay $1,000 to the opposing side” and to “forward the order to the attorney regulators in Maryland” (source [2]); Bloomberg Law reported that “Kusmin L. Amarsingh on Monday was sanctioned $1,000 by the US Court of Appeals for the Tenth Circuit” (source [3]).

A note on sourcing

The load-bearing evidence here is the strongest kind: a signed, public Tier 1 federal appellate order that states the $1,000 sanction, the seven fabricated citations, the ChatGPT admission and the Maryland referral in its own words, not a party’s self-report. The weakest load-bearing source is Bloomberg Law [3], a subscription/paywalled report that could not be captured to the Wayback Machine (its page is login-gated); it is saved only as a live local capture, so a reader cannot independently re-pull it from a public archive. That matters little to the record, because every figure it carries is also stated in the Tier 1 order [1] and in the Wayback-archived Colorado Politics report [2]; Bloomberg is corroboration, not the sole support for any claim.

How this was verified

Method: The primary source is the Tenth Circuit’s signed Order and Judgment (No. 24-1391, filed February 9, 2026, Judge Harris L. Hartz), byte-tied to its Wayback capture via a CDX/SHA-1 digest match. Every quoted figure, the $1,000 FRAP 38 sanction, the seven fabricated citations, the ChatGPT admission, the Maryland referral, was re-checked verbatim against the archived order and against two independent newsroom captures (Colorado Politics, Wayback-archived; Bloomberg Law, live capture). No figure rests on any party’s self-report. Date: Re-verified 2026-08-18.

Sources

1. Tier 1. U.S. Court of Appeals for the Tenth Circuit · Amarsingh v. Frontier Airlines, Inc., No. 24-1391 · Order and Judgment (unpublished; opinion by Judge Harris L. Hartz) · February 9, 2026 · https://www.ca10.uscourts.gov/sites/ca10/files/opinions/010111382504.pdf (archived: https://web.archive.org/web/20260209193841/https://www.ca10.uscourts.gov/sites/ca10/files/opinions/010111382504.pdf)
2. Tier 2. Colorado Politics · “10th Circuit orders lawyer to pay $1,000 for faulty AI citations” · February 9, 2026 · https://www.coloradopolitics.com/2026/02/09/10th-circuit-orders-lawyer-to-pay-1000-for-faulty-ai-citations/ (archived: https://web.archive.org/web/20260315194901/https://www.coloradopolitics.com/2026/02/09/10th-circuit-orders-lawyer-to-pay-1000-for-faulty-ai-citations/)
3. Tier 2. Bloomberg Law · “Appeals Court Sanctions Lawyer Over AI-Hallucinated Errors” (Sam Skolnik) · February 9, 2026 · https://news.bloomberglaw.com/litigation/appeals-court-sanctions-lawyer-over-ai-hallucinated-errors (subscription/paywalled; no public Wayback capture, held as a live local capture only)

Related case files

• Fletcher v. Experian (5th Cir.): a sibling federal appellate sanction for AI-fabricated citations, imposed under the appellate rules.
• Ayinde v. Haringey (UK High Court): the same fact pattern in another jurisdiction, wasted-costs order plus a regulator referral over fabricated authorities.
• McCarthy v. DEA (3d Cir.): a precedential first-impression appellate response to AI-fabricated citations, choosing a public reprimand rather than a fine.
• Arabyads v. Alam (ADGM): the same conduct penalized commercially, via an indemnity-costs award, in a common-law court outside the U.S.