Ethics & professional responsibility
Verify every AI-assisted citation and quotation
AI can return plausible but false authority. Before filing, lawyers must independently verify every citation, quotation, and characterization of a holding.
Practice note
Verification is broader than catching a nonexistent case.
AI output is not verified authority
| Factor | Plausible AI output | Verified legal authority |
|---|---|---|
| Existence | A citation may look complete while identifying no real case. | Confirm the case, reporter, court, and citation in an authoritative source. |
| Support | A real case may not support the asserted proposition. | Read the relevant passage and confirm the holding, context, and procedural posture. |
| Responsibility | The model supplies a draft answer. | The lawyer remains responsible for the truthfulness and legal sufficiency of the filing. |
Example conversion prompt
Verify citations and quotations before filing
List every case citation and quotation in the attached draft. For each item, identify the authoritative source, confirm the exact citation and quotation, and flag any proposition you cannot verify. Do not invent or infer authority. I will independently review every result before filing.Edited transcript
Transcript
Hey lawyers, one of the most common questions I get is, “Aren’t you afraid that Claude is hallucinating cases?” And the answer is yes, terrified in fact.
1. AI Can Produce Plausible but Unverified Authority
The State Bar updated its guidance in April 2026 and combined the duty of candor with the duty of supervision of non-lawyers, stating: “the lawyer’s duty of candor to the tribunal cannot be delegated to AI.”
Of course, correctly citing cases squarely falls under the attorney’s duty of competency as well. AI tools can be problematic. They generate plausible answers, not verified ones.
Sometimes that means a citation looks absolutely perfect, but it is to a case that never existed. The Bar states that the duty goes beyond catching hallucinations and that the attorney is personally responsible for the truthfulness and legal sufficiency of everything filed.
2. Verify Every Citation, Quotation, and Characterization
Of course, that is not a new duty. That has always been the duty. So the rule is simple: if AI helped write it, you verify it.
Every cite, every quote, every characterization of a holding, before it goes anywhere near a judge.
3. Use Reliable Sources for the Check
And the good news is verification can be fast. You can use tools like Westlaw Quick Check or Lexis. You can use CourtListener and hook it up to Claude, or you can do it the old-fashioned way and check the cases.
Follow me for more advice on using AI in your legal practice.