Missouri: AI Ethics Guidance for Law Firms

Bottom line for a 5-50 attorney Missouri firm: Missouri has a non-binding informal advisory opinion (Informal Opinion 2024-11, April 25, 2024) interpreting the binding Missouri Rules of Professional Conduct, paired with two published Court of Appeals sanctions decisions for AI-hallucinated citations in 13 months. Citation verification before filing is the single most actionable obligation, given Kruse v. Karlen’s $10,000 sanction and Stevens v. BJC’s “abuse of the adversary system” language. The biggest risk is filing in a Missouri judicial circuit with a local AI disclosure rule (reported in the 46th, 17th, 20th, and 7th) without checking; non-disclosure plus an unverified citation is the documented sanctions pattern.

Start with: a written AI use policy, a citation verification protocol signed annually, and a circuit-by-circuit disclosure compliance check before each filing.

Missouri Informal Opinion 2024-11

Citation: Missouri Informal Opinion 2024-11, issued April 25, 2024, by the Office of Legal Ethics Counsel and Advisory Committee of the Supreme Court of Missouri. Indexed at the informal opinions search.

Status: Informal advisory opinion. Non-binding. Published as “initial guidance” and “not intended to be an exclusive list of ethical considerations.” The underlying Missouri Rules of Professional Conduct cited in the opinion are binding.

What it requires

• Competence (Rule 4-1.1): Attorneys must educate themselves on the types of generative AI available, understand the risks and benefits, and keep abreast of changes in practice including technology.
• Confidentiality (Rule 4-1.6(a), (c)): Before using any generative AI platform, a lawyer must assess the platform’s terms of service, security measures, data usage policies, and data sources to ensure client information is protected. The lawyer must also make reasonable efforts to prevent inadvertent or unauthorized disclosure of client information.
• Verification: All AI-generated content must be reviewed and verified for accuracy before use; the opinion states that generative AI tools are not always accurate.
• Candor (Rule 4-3.3(a)): A lawyer must not submit AI-generated content containing false statements of material fact or law without verification.
• Court orders (Rule 4-3.4(c)): When courts have standing orders or local rules restricting or requiring disclosure of AI use, attorneys must comply.
• Professional independence (Rule 4-5.4): A lawyer cannot rely solely on AI-generated content; independent professional judgment must be maintained.
• Supervision (Rules 4-5.1, 4-5.3(c)): Supervisory attorneys must ensure subordinates and nonlawyer staff comply; partners who know of noncompliant conduct and fail to take remedial action bear ethical responsibility.

What it recommends

• Develop a firm-wide AI use policy.
• Provide training to lawyers and nonlawyer staff.
• Review data privacy laws beyond the Rules of Professional Conduct.

Rules cited

Rules 4-1.1 (Competence), 4-1.5(a) (Fees), 4-1.6(a), (c) (Confidentiality), 4-3.3(a) (Candor), 4-3.4(c) (Fairness to Opposing Party and Counsel), 4-5.1 and 4-5.3(c) (Supervision), 4-5.4 (Professional Independence).

Notable gaps

Several gaps stand out. The opinion does not require client disclosure that AI was used. Client consent for use of confidential information in AI platforms is not required either. Fee implications under Rule 4-1.5(a) get raised but no analysis follows. A reasonable data security assessment is left undefined.

What federal courts in Missouri require for AI use in filings

The U.S. District Court for the Eastern District of Missouri has published an AI accountability policy. Under the policy, by presenting any pleading, written motion, or other paper, attorneys and self-represented parties acknowledge they will be held responsible for its contents, including any portion generated with artificial intelligence. The policy is enforceable through Federal Rule of Civil Procedure 11(b). The Western District of Missouri has not published an equivalent district-wide statement; the operative federal default there is Fed. R. Civ. P. 11.

What Missouri state courts require for AI use in filings

As of April 2026, no statewide Missouri rule requires AI disclosure. There is no Supreme Court of Missouri AI standing order equivalent to mandatory disclosure orders in some federal districts. At least four Missouri judicial circuits have adopted local AI disclosure rules. The 7th Judicial Circuit (Clay County) Local Rule 3.3.1 (adopted July 25, 2024) is verified verbatim in the circuit’s published local rules. Any person submitting a pleading or filing using a generative AI tool to conduct legal research or to draft a pleading or document must disclose the use, identify the specific tool used, and describe the manner in which it was used. The rule also reminds parties that Missouri Supreme Court Rule 55.03(c) continues to apply and that mere reliance on an AI tool will not be presumed to constitute reasonable inquiry. Analogous local rules at Rule 3.3 are maintained by the 17th and 46th Judicial Circuits (indexed by the Missouri Courts office at file IDs 51228 and 135553 respectively). In the 20th Judicial Circuit, Local Rule 17 applies. Verbatim text for the 17th, 20th, and 46th Circuit rules should be confirmed by direct review of each circuit’s published local rules before filing.

Has anyone been sanctioned for AI use in Missouri?

Kruse v. Karlen, 692 S.W.3d 43 (Mo. Ct. App. E.D. 2024)

In an opinion decided February 13, 2024 (No. ED111172), the Missouri Court of Appeals, Eastern District, dismissed an appeal. Of the 24 case citations in the appellant’s brief, 22 were entirely fictitious AI-generated citations. The court awarded $10,000 in sanctions to the respondent under Missouri Supreme Court Rule 84.19 (frivolous appeals). The court warned that it would “not permit fraud on this Court” by represented or self-represented parties. Rules cited: Mo. Sup. Ct. Rules 84.04, 84.19, 55.03(c)(3).

Stevens v. BJC Health Sys., No. ED112759 (Mo. Ct. App. E.D. Mar. 18, 2025)

The Missouri Court of Appeals, Eastern District, addressed a brief containing six cases the court could not locate, suggesting AI use. It characterized the conduct as “an abuse of the adversary system.” The court warned that “the use of AI in drafting legal documents may lead to sanctions if the party fails to perform a critical review of the end-product.” It decided the appeal adversely to appellant in part because unsupported citations undermined brief credibility. No S.W.3d bound-reporter citation has been located as of this entry’s date; cite by docket. Docket page: ED112759 (Justia mirror).

What AI-related rules are pending in Missouri?

As of April 2026, no Missouri legislation directly regulating attorney AI use, court disclosure, or bar rules has been enacted or is pending. Adjacent pending bills address other AI domains, not attorney conduct: HB 1769 on AI non-sentience and responsibility, SB 1117 on nonconsensual intimate deepfakes, and SB 1012 on AI-generated depiction consent and watermarks.

How do malpractice carriers in Missouri treat AI use?

The Office of Legal Ethics Counsel did not include explicit carrier language in Opinion 2024-11. Carriers active in Missouri have taken the position that if an attorney blindly relied on AI hallucinations without validation, no professional service may have been rendered, potentially eliminating coverage. Verification, supervision, and confidentiality obligations in Opinion 2024-11 map directly onto LPL coverage conditions. Together, the Kruse and Stevens decisions create a documented Missouri-specific exposure path from unverified AI citations to appellate sanctions and bar exposure.

What does my Missouri malpractice carrier ask about AI at renewal?

The dominant Missouri LPL carriers have not published Missouri-specific AI application items as of this entry’s date. The substantive standard the firm should prepare against is Opinion 2024-11 plus the binding Rules of Professional Conduct it interprets, supplemented by the verification expectation made explicit in Kruse and Stevens. Firms should be ready to produce a written AI policy, platform security review documentation for each approved tool, a citation verification protocol, training records, and matter-level AI use logs (full list below). Firms practicing in circuits reported to have local AI disclosure rules should also be ready to show a circuit-by-circuit disclosure workflow.

What documentation should a Missouri firm keep on file?

Month one (foundational)

1. (Owner: managing partner + firm administrator) Written AI use policy covering approved tools, permitted uses, verification requirements before submission, and the responsible attorney; updated annually or when material new tools are adopted. Anchored in Rules 4-5.1 and 4-5.3.
2. (Owner: litigation lead) Citation verification protocol requiring every legal citation to be verified against a primary source before filing, signed annually by each attorney. Directly addresses the Kruse v. Karlen and Stevens v. BJC sanctions pattern under Rule 4-3.3(a).
3. (Owner: litigation lead) Circuit-by-circuit disclosure compliance check tracking whether each court the firm files in has an AI disclosure rule (the 46th, 17th, 20th, and 7th Judicial Circuits as currently reported). Retain completed disclosure certifications for each filing in those circuits. Required by Rule 4-3.4(c).

Months two and three (operational documentation)

1. (Owner: firm administrator + outside IT) Platform security review documentation for each approved AI tool: a written record that the firm reviewed the platform’s terms of service, data security practices, and data retention or deletion policies before adoption, with the version of the terms reviewed and the date retained. Required by Rule 4-1.6(c) and Opinion 2024-11.
2. (Owner: firm administrator) Staff AI training records showing lawyers and nonlawyer staff received training on AI risks and verification obligations. Supports Rules 4-5.1 and 4-5.3.

Months four to six (per-matter discipline)

These are recurring practices, not one-time projects: each new matter exercises them.

1. (Owner: matter lead attorney) Matter-level AI use log for any matter where AI was used in drafting, research, or analysis: what tool was used, for what purpose, and who performed the verification review.
2. (Owner: managing partner) Annual professional liability insurance review confirming the firm’s LPL policy covers AI-assisted work product and that no AI-specific exclusion has been added by endorsement.
3. (Owner: managing partner) Periodic review schedule for updated Office of Legal Ethics Counsel guidance, new circuit court AI rules, and additional Missouri appellate decisions following Kruse and Stevens.

We are building practitioner resources for firms working through this list. The monthly update covers new resources as they ship.