Missouri.
Attorney AI ethics guidance status for Missouri as of May 9, 2026. Informal bar guidance.
Missouri bar AI ethics status. #
The Missouri Bar issued Informal Opinion 2024-11 in 2024, providing guidance on attorney AI use. Informal opinions in Missouri are advisory rather than binding but are routinely treated as persuasive in disciplinary proceedings.
Authoritative source: https://mo.legalethics.us/
Last verified: . If this row text disagrees with the linked source, the source controls.
What this means in practice. #
For practitioners admitted in Missouri, the formal guidance above is the binding professional-conduct anchor for AI use. The recurring duties: (1) maintain competence in the AI tool, (2) protect client confidentiality (do not submit confidential material to public-version AI tools), (3) supervise AI output, and (4) verify all factual and legal content before submission.
Cross-jurisdictional consideration: ABA Formal Opinion 512 (July 2024) is broadly consistent with the Missouri guidance and serves as a federal anchor for multi-state practitioners. Where Missouri guidance is more specific or more restrictive than ABA Op. 512, the Missouri guidance controls within Missouri.
Comparison to ABA Op. 512. #
Missouri Informal Op. 2024-11. Informal opinions in Missouri are advisory, not binding. The opinion tracks ABA Op. 512 closely. Note that disciplinary committees and courts in Missouri routinely treat informal opinions as persuasive, so the practical effect approximates a formal opinion.
Federal court AI standing orders affecting Missouri practitioners. #
No widely-noted court-wide or individual-judge AI standing orders affecting Missouri's federal districts have surfaced as of May 2026. Individual judges may have issued orders that are not in our representative list. Practitioners should consult each assigned judge's standing orders before filing in any federal matter. The comprehensive corpus of federal-judge AI orders is maintained by Bloomberg Law and Law360 (both paywalled).
Last verified: . The comprehensive corpus of federal-judge AI orders is maintained by Bloomberg Law and Law360.
AI case-law context for Missouri. #
Missouri sits within the 8th Circuit (United States Court of Appeals for the 8th Circuit). Decisions of the 8th Circuit are binding on the federal courts within Missouri; state-court decisions of the Missouri appellate system bind Missouri's state courts; Supreme Court decisions are binding on everyone. The Supreme Court has not yet issued a decision directly addressing attorney AI use, so the controlling case law is at the circuit and district levels:
has yet directly addressed AI use in legal practice. Persuasive authority comes from Mata v. Avianca (S.D.N.Y.), Park v. Kim (2d Cir.), and Tremblay v. OpenAI (N.D. Cal. 2024).
Several E.D. Mo., W.D. Mo., D. Minn., and D. Neb. judges have issued individual standing orders on AI use. Practitioners should consult each assigned judge's orders before filing.
Practitioners in Missouri should treat the cases above as the operating framework for AI-related conduct until Missouri-specific binding precedent or Missouri bar guidance controls a particular question. The verification duty under Mata and Park v. Kim has been routinely cited in sanctions matters across all federal circuits including the 8th Circuit.
Missouri legal landscape. #
- Eastern District of Missouri (E.D. Mo.)
- Western District of Missouri (W.D. Mo.)
The Missouri Bar is a mandatory unified bar. Two federal districts.
Most US states have adopted the substance of ABA Model Rule 1.1, Comment 8 — that the duty of competence requires lawyers to keep abreast of the benefits and risks of relevant technology. Whether Missouri has adopted Comment 8 verbatim, in modified form, or relies on the underlying Rule 1.1 text alone, the substantive duty of technological competence applies to AI-related practice in Missouri.
Missouri-specific FAQ.
Has the Missouri bar issued formal AI ethics guidance?
Yes. Missouri has issued: Informal Opinion 2024-11 (2024). The opinion applies the Missouri Rules of Professional Conduct to attorney AI use. The primary source link in §01 above is authoritative; the comparison to ABA Op. 512 in §03 highlights where Missouri aligns with or diverges from the ABA framework.
Which federal districts cover Missouri?
Missouri has 2 federal districts: Eastern District of Missouri (E.D. Mo.) and Western District of Missouri (W.D. Mo.). Federal AI standing orders are typically issued at the individual-judge level. The Bloomberg Law and Law360 trackers maintain the comprehensive corpus of federal-judge AI orders nationwide.
Does Missouri have a mandatory unified bar?
Yes. The Missouri bar is a mandatory unified bar — all licensed attorneys must be members. AI ethics guidance issued by the bar applies to all admitted practitioners. Discipline for AI-related misconduct flows through the bar's formal disciplinary regime under the Supreme Court of Missouri's plenary supervisory authority.
Does AI vendor diligence apply in Missouri?
Yes. The supervisory duty under Missouri's analog to Rule 5.3 (responsibilities regarding nonlawyer assistance) applies to AI vendor relationships. North Carolina's 2024 FEO 1 frames AI vendors explicitly under Rule 5.3, and that framing has been treated as persuasive in other jurisdictions including Missouri. Vendor diligence — privacy-policy review, data-retention terms, training-on-customer-data clauses — is a precondition to selecting an AI tool for client work.