What must a Missouri lawyer do after learning that a client gave material false deposition testimony?

Plain-English summary

A client testified in a deposition that the client was employed and stated an income, consistent with what the client had previously told the lawyer. Days later, the client admitted having been unemployed for at least three months.

Rule 4-3.3 applies to depositions because they are ancillary proceedings conducted under a tribunal's adjudicative authority. If the lawyer actually knows the client's material evidence was false, Rule 4-3.3(a)(3) requires reasonable remedial measures. The lawyer resolves doubts in the client's favor but cannot ignore an obvious falsehood.

The lawyer first remonstrates with the client, explains the candor duty, and seeks cooperation in withdrawing or correcting the testimony. If the client refuses and withdrawal would not undo the falsehood's effect, further measures include disclosure to the tribunal if necessary, despite Rule 4-1.6 confidentiality. Any disclosure is limited to what is reasonably necessary.

The client's plan to testify truthfully at a later hearing does not remedy the earlier deposition. Rule 4-3.3 compliance normally does not require withdrawal, but Rule 4-1.16(a) does require seeking leave if remedial measures cause such extreme relationship deterioration that competent representation is no longer possible.

In practice

Under this opinion, later truthful testimony does not substitute for correcting known material false deposition evidence. The remedial sequence moves from client consultation and voluntary correction to necessary, limited tribunal disclosure, with withdrawal required only under the deterioration condition the opinion identifies.

Common questions

Q: Does Rule 4-3.3 apply to a deposition?

A: Yes. The opinion treats a deposition as an ancillary proceeding under a tribunal's adjudicative authority.

Q: What level of certainty triggers the duty?

A: The lawyer must know the material evidence is false. Knowledge means actual knowledge and may be inferred, while doubts are resolved for the client and obvious falsehoods cannot be ignored.

Q: What is the first remedial step?

A: The lawyer explains the candor duty and seeks the client's cooperation in withdrawing or correcting the false testimony.

Q: May confidentiality prevent disclosure to the tribunal?

A: No, if disclosure is necessary to remedy the false evidence. The disclosure must be limited to what is reasonably necessary.

Q: Does truthful testimony at the next hearing satisfy the duty?

A: No. The opinion says that does not relieve the lawyer of the duty to remedy the deposition testimony.

Background and rules framework

Rule 4-3.3(a)(3) governs false evidence and reasonable remedial measures; Rule 4-3.3(c) makes the duty controlling over confidentiality when necessary. Rules 4-1.2(g), 4-1.4, 4-1.6(c), and 4-1.16(a) govern consultation, limited disclosure, and possible withdrawal.

Citations and references

Rules of Professional Conduct:

• Missouri Rules 4-1.0(f), 4-1.2(g), 4-1.4, 4-1.6, 4-1.6(c), 4-1.16(a), 4-3.3(a)(3), and 4-3.3(c)
• Missouri Rule 4-3.3 Comments [1], [8], [10], and [15]

See also

• Rhode Island Ethics Op. 91-76: False Deposition Testimony
• Washington Advisory Op. 1149: Client's False Deposition Testimony
• Missouri Informal Op. 2026-03: False Discovery Document

Source

• Landing page: Missouri Informal Opinion 2020-24

Original opinion text

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

QUESTION: Client testified at a deposition that Client was currently employed and testified as to the income Client was earning. The testimony was consistent with what Client had told Attorney before the deposition. A few days after the deposition, Client informed Attorney that Client had not been employed for at least three months. Documentation of Client’s employment has not been requested in discovery. If Client testifies truthfully about the issues at an upcoming hearing, does Attorney have an ethical duty to take any action regarding the deposition testimony?

ANSWER: Rule 4–3.3, Candor Toward the Tribunal, governs the conduct of a lawyer representing a client in the proceedings of a tribunal, including ancillary proceedings conducted pursuant to a tribunal’s adjudicative authority, such as a deposition. Rule 4–3.3, Comment [1]. Rule 4–3.3(a)(3) prohibits a lawyer from offering evidence the lawyer knows to be false. “Knows” denotes actual knowledge of the fact in question and may be inferred from the circumstances. Rule 4–1.0(f). Attorney should resolve any doubts about the veracity of Client’s testimony in favor of Client, but Attorney cannot ignore an obvious falsehood. Rule 4–3.3, Comment [8]. If Attorney has come to know that material evidence offered by Client in the deposition is false, Rule 4–3.3(a)(3) requires Attorney to “take reasonable remedial measures, including, if necessary, disclosure to the tribunal.” Attorney should remonstrate with Client, advising Client of Attorney’s duty of candor toward the tribunal and seeking Client’s cooperation in withdrawing or correcting the false testimony. See Comment [10]; see also Rules 4–1.2(g) and 4–1.4. If Client will not cooperate, and if withdrawing from the representation will not undo the effect of Client’s false testimony, Attorney must take further remedial measures, including, if necessary, disclosure to the tribunal, even if the disclosure requires Attorney to reveal information that otherwise would be protected by Rule 4–1.6. Rule 4–3.3(c) and Comment [10]. Any disclosure to the tribunal would be limited to what is reasonably necessary to remedy the situation. Rule 4–1.6(c) and Comment [10]. Client’s agreement to testify truthfully about the issue at an upcoming hearing does not relieve Attorney of the duty to take reasonable remedial measures as to the deposition testimony, as required by Rule 4–3.3(a)(3). Normally, Attorney’s compliance with Rule 4–3.3 does not thereafter require Attorney to seek leave to withdraw from the representation. See Rule 4–3.3, Comment [15]. However, if the remedial measures result in an extreme deterioration of the client-lawyer relationship such that competent representation cannot be provided, Rule 4–1.16(a) requires Attorney to seek leave to withdraw.