What ethics duties apply when a Missouri firm uses AI software that listens to depositions and suggests questions in real time?

Plain-English summary

A firm considered web-based AI software that listened during depositions, produced searchable real-time transcripts, suggested follow-up questions, and compared testimony with uploaded exhibits, pleadings, and prior statements. The vendor promised confidentiality, no training on firm data, and continuing protection after termination.

The ethics office did not endorse the product or approve a firm policy. It required the firm to understand changing capabilities and risks, verify outputs independently, charge only reasonable fees reflecting efficiencies, obtain informed consent before uploading confidential information, and keep professional judgment independent.

Management duties required clear policies, training, secure data practices, and reasonable investigation of the vendor's credentials, security, confidentiality commitments, and available forum for legal relief. The firm also had to prevent one client's data from being used for another.

Whether real-time listening required notice to the client, court, opposing counsel, or deponent depended partly on substantive privacy law, discovery rules, local rules, and court orders, which the office did not interpret. The lawyer at minimum could not misrepresent the tool's use or make a partially true but misleading omission.

In practice

Under the published summary, vendor promises were inputs to the firm's continuing assessment, not a substitute for it. The lawyer retained responsibility for informed consent, security, output verification, legal compliance, and independent judgment.

Common questions

Q: Did the opinion approve the particular vendor?

A: No. The office expressly declined to endorse software or develop firm policy.

Q: When was client consent required?

A: Before confidential client information was entered into the AI system.

Q: Could the lawyer rely solely on generated questions or analysis?

A: No. The lawyer had to verify output accuracy and maintain independent judgment.

Q: Did a deposition notice automatically authorize AI listening?

A: The opinion did not decide that legal question.

Q: When did other participants need notice?

A: When applicable privacy law, discovery rules, local rules, or court orders required it, and whenever silence or a partial statement would be materially misleading.

Background and rules framework

The opinion applied duties of competence, communication, reasonable fees, confidentiality, court-order compliance, truthfulness, respect for third-party rights, management, vendor supervision, and professional independence.

Citations and references

Missouri Rules of Professional Conduct:

• Rules 4-1.1, 4-1.4, 4-1.5, and 4-1.6
• Rules 4-3.4(c), 4-4.1(a), and 4-4.4(a)
• Rules 4-5.1, 4-5.3, and 4-5.4

Other opinions cited:

• Missouri Formal Opinion 123
• Missouri Informal Opinions 2018-09, 2021-03, and 2024-11

See also

• Missouri Formal Op. 123: Secret recording
• New Mexico Ethics Op. 2024-004: Generative AI
• Missouri Formal Op. 127: Electronic client files

Source

• Landing page: Missouri Informal Opinion 2026-09

Original opinion text

Reproduced from the official source for research purposes. The linked source is authoritative.

Question: Lawyer asks about the ethical propriety of Law Firm’s possible use of a particular web-based, artificial intelligence (“AI”) deposition assistance software (“Software”). The Software “listens” while depositions are ongoing and provides real-time searchable transcripts. It also provides follow-up questions to lawyers and cross-references deponents’ statements with prior testimony, exhibits, and pleadings that have been uploaded into the Software’s system. Software Company, a vendor, has made numerous representations to Lawyer and Law Firm regarding how it operates and its security measures, and will agree in its contract that: (1) all data submitted to the Software Company is confidential and privileged material and will be treated in compliance with the Rules of Professional Conduct; (2) none of the Law Firm’s data will be used to train AI; and (3) Software Company will maintain confidentiality of the uploaded information into perpetuity even if Law Firm cancels its contract.

Lawyer asks the following questions:

• Whether it is ethically permissible for Law Firm to use this Software?

a. If so, what ethical issues should Law Firm consider when developing a policy for the Software’s use?

• Whether the Software’s real-time “listening” feature complies with the Rules of Professional Conduct? This includes addressing whether:

a. a deponent’s general consent to the taking of a deposition is sufficient consent to encompass the use of real-time AI analysis of the deponent’s testimony; and

b. it is necessary to disclose the Software’s use to the client, court, opposing counsel, and the deponent prior to or during the deposition?

Answer to Question 1:

This office does not endorse or approve the use of a particular software or vendor by a lawyer or law firm. Software terms and conditions, as well as third-party vendors, may change throughout the term of a contract between Law Firm and Software Company. Law Firm will have to use its independent professional judgement in determining whether the Software’s use is permissible under the Rules of Professional Conduct. Similarly, this office does not develop or approve specific policies for lawyers or law firms and cannot give legal advice.

Law Firm should consider the following Rules when deciding whether to use Software and for developing policies for use of any AI for deposition assistance software.

• Rule 4–1.1 – Competence. This rule requires a lawyer to have a reasonable understanding of the capabilities and limitations of AI software, including the risks posed by the use of the software. This is an ongoing obligation, and a lawyer must stay abreast of any changing risks or benefits. It also requires a lawyer to independently verify the software’s output for accuracy and to consider whether the use of the software meets the client’s interests and objectives. See also Rule 4–1.1, Comment [6].

• Rule 4–1.5 – Fees. This rule requires a lawyer to communicate to the client at the time of commencing the representation or soon thereafter, preferably in writing, any charge or fee to be assessed to the client for the use of the AI software. Any hourly fees charged to the client by lawyers or paralegals using the software must be reasonable, i.e., the amount of time charged must reflect the efficiencies provided by the use of the software.

• Rule 4–1.6 – Confidentiality. Whether AI software may be ethically used requires an assessment of the risk that confidential client information may be revealed or accessed by others outside the firm. It also requires an assessment of the risk that confidential information may be improperly used by others in the law firm. See also Missouri Informal Opinion 2018–09. This could occur when the AI software uses confidential information from one client to assist another client. A lawyer must obtain informed consent from the client to the use of the AI software before inputting confidential client information into the AI software.

• Rule 4–1.4 – Communication. A lawyer should discuss the use of the AI software with the client as part of obtaining informed consent as required by Rule 4–1.6.

• Rule 4–3.4(c) – Court Orders. Use of AI deposition software requires compliance with any court rules or orders addressing the use of AI and compliance with all discovery rules.

• Rule 4–5.1 – Managerial Responsibilities of Other Attorneys. This rule requires clear policies regarding the permissible use of Software by lawyers in the firm. It also requires training for Software’s use, including the best practices for secure data handling, complying with privacy laws, and complying with Rule 4–1.6.

• Rule 4–5.3 – Managerial Responsibilities Concerning Nonlawyer Assistants. This rule requires a law firm to make sure that Software Company takes reasonable steps to ensure work is done competently and to protect client confidences. This would require a reference check of a vendor’s credentials, understanding the vendor’s security policies and protocols, using confidentiality agreements, and ensuring the availability and accessibility of a legal forum for legal relief for violation of the vendor agreement. See also Missouri Informal Opinion 2021–03.

• Rule 4–5.4 – Professional Independence. A lawyer must maintain independent judgment when using AI software and not rely solely on content created by the generative software.

Lawyer should also refer to Missouri Informal Opinion 2024–11 for additional guidance under the Rules of Professional Conduct for development of a generative AI use policy.

Answer to Question 2:

The issue of whether the Software’s real-time “listening” feature complies with the Rules of Professional Conduct is a complex issue which involves the application of evolving substantive law, court rules, and various Rules of Professional Conduct.

This office cannot comment or opine on the specific issue of whether the notice of deposition constitutes consent by the deponent to use of the Software. This would require interpretation of substantive privacy laws, procedural discovery rules, and other rules, all of which are beyond the scope of the Rules of Professional Conduct.

The Rules of Professional Conduct do not specifically address whether a lawyer must advise the client, the court, opposing counsel, or the deponent of the use of AI software. As discussed above, it is necessary to obtain informed client consent for the use of AI software if confidential client information is uploaded into the AI system.

There are several Rules of Professional Conduct that may need to be considered regarding providing notice to the other entities Lawyer has listed in the question. Rule 4–3.4(c) requires a lawyer to obey court rules or orders. Rule 4–4.4(a), in turn, provides that in representing a client, a lawyer shall not use methods of obtaining evidence that violate the legal rights of a person. Thus, if local rules, standing court orders, discovery rules, or privacy laws require notice to any of the entities set forth in your question, a lawyer must provide such notice.

If there are no local rules, standing court orders, discovery rules, or privacy laws requiring disclosure, Rules 4–4.1(a) should be considered. Rule 4–4.1(a) requires that a lawyer not knowingly make a false statement of material fact to a third person. Under this rule, partially true, but misleading statements or omissions as to the use of AI software, may violate the Rule. See Rule 4–4.1, Comment [1].

Formal Opinion 123 also may offer insight into the application of the Rules of Professional Conduct to the questions Lawyer poses. This opinion addresses a lawyer recording a conversation without notification to the other party. This could be viewed as similar to the use of the “listening” feature of the Software without providing notice to all interested parties. The Missouri Advisory Committee opined that in some circumstances an attorney may record a conversation, to which the attorney is a party, without notifying the other party to the conversation if that is consistent with other law. The Missouri Advisory Committee noted that there were certain circumstances when notification was required. These include when: (1) laws prohibit the recording in the jurisdiction in which the recording would occur, (2) the attorney states or implies that the conversation is not being recorded, and (3) the conversation is between the attorney and the client. The Missouri Advisory Committee noted that the list of exceptions is not exhaustive.

Based upon the requirements of Rule 4–4.1 and Formal Opinion 123, at a minimum, a lawyer should not misrepresent the use of any AI software. In accordance with Rules 4–3.4(c) and 4–4.4(a) and Formal Opinion 123, a lawyer should also review substantive law, procedural rules, and court orders to ensure that there are no disclosure requirements. If any disclosure requirements exist, a lawyer must comply with the requirements.