The Nebraska Supreme Court has suspended Omaha attorney Greg Lake from practicing law after his appellate brief in a divorce case contained 57 defective citations out of 63 total — including 20 AI-generated hallucinations: fictitious cases, fabricated quotations, and references to statutes that do not exist. Lake repeatedly denied using AI in preparing the brief. The court ruled his explanation “lacks credibility.” The case is the latest and most severe sanction in a rapidly accelerating wave of AI citation errors hitting legal professionals in 2026.
What Happened
Lake filed an appellate brief in a Nebraska divorce proceeding. When opposing counsel and the court began checking his citations, the scope of the problem became clear: of 63 total citations in the brief, 57 were defective. Within those defective citations, 20 were AI hallucinations — cases that do not exist, quotations attributed to cases that say no such thing, and references to statutory provisions that have never been enacted.
AI hallucination in legal citations follows a well-documented pattern: when asked to find cases supporting a legal argument, AI models often generate plausible-sounding citations — correct case name format, correct jurisdiction, correct year — that refer to cases that do not exist or cases that exist but said something entirely different. The output looks authoritative to anyone who doesn’t verify it against the actual legal databases.
When confronted, Lake denied using AI to prepare the brief — a denial the Nebraska Supreme Court explicitly found not credible. The suspension followed a March discipline referral. The court’s ruling establishes that denying AI use when evidence suggests otherwise compounds rather than mitigates the disciplinary consequence.
The Scale of AI Citation Sanctions in 2026
The Lake case is the most severe outcome yet, but it is not an isolated incident. US courts have imposed at least $145,000 in sanctions against attorneys for AI citation errors in Q1 2026 alone. The pattern that has emerged across jurisdictions:
- Attorneys use AI tools — most commonly ChatGPT or similar general-purpose models — to draft briefs or identify supporting cases
- The AI generates plausible but fictitious citations that the attorney either doesn’t verify or verifies inadequately
- The fictional citations appear in filed court documents
- Opposing counsel or the court discovers the errors during routine verification
- The attorney faces sanctions ranging from fines to suspension
The first high-profile case of this type — involving attorneys who filed a brief with AI-hallucinated citations in the Southern District of New York — resulted in $5,000 in sanctions in 2023. The trajectory since then has been toward increasingly severe consequences as courts have made clear that the defense of “I didn’t know AI could do this” is no longer available.
Why This Keeps Happening
The fundamental issue is not that lawyers are using AI — it’s that they’re using general-purpose language models for a task those models handle unreliably. AI models like ChatGPT and Claude are trained to be helpful and to produce confident-sounding, well-formatted responses. Legal citation is a domain where the format of a hallucinated citation (correct case name structure, jurisdiction, year) is indistinguishable from a real citation without independent verification against legal databases like Westlaw or LexisNexis.
The workflow failure is consistent across cases: attorneys use AI to draft, assume the AI has done the research correctly, and submit without running citations through verification databases. For experienced attorneys, this represents a breakdown in professional practice standards that have existed for decades — citation verification is a foundational step in legal brief preparation that AI does not replace, it only introduces new failure modes for.
What the Legal Profession Needs to Do
Bar associations across the US are actively developing AI practice guidelines in response to the growing sanctions wave. The emerging consensus:
- AI can assist with drafting, issue spotting, and research direction — but not with citation generation
- Every citation must be independently verified against authoritative legal databases before filing, regardless of how the first draft was produced
- AI use must be disclosed in jurisdictions with disclosure requirements — and attempting to conceal AI use when evidence suggests otherwise is itself a disciplinary violation
Conclusion
The Lake suspension is a warning that the consequences of AI citation errors in legal filings are now career-ending rather than merely embarrassing. The legal profession is not unique in this risk — any domain where AI-generated outputs are trusted without independent verification faces analogous exposure. The lesson extends to anyone using AI to produce factual claims that will be relied upon in high-stakes contexts. Browse our directory to explore AI writing tools and understand where they work reliably and where they require human verification.
