McSweeney Cynkar & Kachouroff PLLC
A Colorado federal court sanctions a law firm over a brief with nearly thirty defective citations
In July 2025 a US federal court in Colorado sanctioned a law firm and its lead counsel $3,000 jointly, and co-counsel $3,000, after a trial brief contained nearly thirty defective citations, including cases that do not exist. Lead counsel told the court the draft was run through AI and he did not check it.
Key figures
Copied exactly from the sources. Copy any figure with its citation.
nearly thirty
Defective citations in the filed brief, as counted by the court in its earlier show-cause order1
$3,000
Sanction on the law firm and its lead counsel, jointly and severally1
$3,000
Sanction on co-counsel, individually1
What it took
Cost, team size and timeline were not disclosed in the sources.
The problem
In a civil case in Colorado, the defendants' lawyers filed a brief opposing a pre-trial request to exclude evidence (a motion in limine). The court found that the brief, filed on 25 February 2025, contained nearly thirty defective citations. They included misquoted cases, legal rules that the cited cases do not contain, cases attributed to the wrong court, and cases that do not exist.
What they built
The record does not describe a built system. It shows a law firm using generative AI as part of drafting a court brief. At the pre-trial conference the judge asked lead counsel whether the brief had been generated with AI. He answered that he had written an outline and a draft himself and then ran it through AI. The order records that he personally did not check the citations and accepted responsibility for that. Co-counsel had been given the job of checking citations.
How they did it
The court opened an inquiry after the conference and required counsel to explain in writing why sanctions should not follow. Counsel replied that an earlier draft had been filed by mistake and that a correct version existed. The court compared the file names, email times and edit history. It found that the draft counsel called the final one contained the same errors as the filed brief, including cases that do not exist. It also found that the supposedly correct version still contained errors. It was not persuaded that a different version had been ready to file.
What went wrong
The court held that counsel had not made a reasonable inquiry into whether the brief's legal arguments were supported by existing law, which Rule 11 requires of every lawyer who signs a filing. It said neither counsel explained how the citations got into any draft without the use of generative AI or gross carelessness. It found that blind reliance on another lawyer can be an improper handoff of a duty that cannot be delegated. It also noted that the same lawyers filed corrections for similar errors in another federal case a week after the show-cause order, among them references to cases that are not real. The court described the firm's written response as defiant in tone.
Results
On 7 July 2025 the court sanctioned the law firm and lead counsel, jointly and severally, $3,000, and co-counsel $3,000, payable by 4 August 2025. It did not extend the sanctions to the clients, because lead counsel confirmed he had not told them about the AI tools he uses. The order cites earlier AI-citation sanctions in other US courts, of between $3,000 and $6,000, as comparison points.
Lessons for your project
Make a named person responsible for checking every citation in a filing against the original source. In this case lead counsel accepted that the brief had not been checked, and the court held that handing the check to someone else did not remove his duty.
Set rules for AI use that apply to senior staff too: which tools are allowed, what must be verified by hand and who signs off. The court said using AI does not excuse the duty to check what is filed.
Keep dated drafts and records of who did what. The court tested the firm's claim that the wrong draft was filed against file names and email times, and found nothing to support it.
Answer a regulator or court plainly. The court called the firm's response to its questions defiant and said the explanation was contradicted by the firm's own documents.
Caveats
- The court order is the only source. It records what counsel told the court and what the court concluded. We have not reviewed any later proceedings.
- The order does not say which AI tool produced the citations. The court said the errors had no explanation other than generative AI or gross carelessness. In a declaration quoted by the court, lead counsel said he uses a range of AI tools in his practice; none is identified as the source of these citations.
- The filing date is the day the brief was filed (25 February 2025). The sources do not say when the AI was used.
- Counsel's account was that an earlier draft was filed by mistake. The court did not accept that account on the record before it.
- The sanctions are small in money terms. The significance is the court's ruling that Rule 11, the US rule that makes a lawyer certify a filing is grounded in law, applies fully when AI is used.
Sources
- Order, Coomer v. Lindell et al., Civil Action No. 22-cv-01129-NYW-SBP, Doc. 383
US District Court for the District of Colorado · 2025-07-07 · Filing · storage.courtlistener.com
Summarized in our own words from the sources above. Spotted an error? See corrections.