May a Missouri lawyer join a firm adverse to a client the lawyer substantially represented at the old firm?

Plain-English summary

The lawyer had represented Client A through depositions and motions, even without entering an appearance or handling daily communications. Rule 4-1.9(a) therefore governs after the move.

Same-or-substantially-related representation of materially adverse Client B requires Client A's informed consent confirmed in writing. Without it, Rule 4-1.10(a) imputes the conflict to the new firm. The opinion states Missouri does not recognize screening under Rules 4-1.9 or 4-1.10; waiver of firm disqualification must satisfy Rule 4-1.7 through Rule 4-1.10(c).

In practice

Under this opinion, substantive work creates former-client duties despite no appearance or daily role, and a screen does not protect the new firm.

Common questions

Q: Did the lawyer represent Client A? A: Yes, through depositions and motions.

Q: Can a screen cure the conflict? A: No under the rules applied.

Q: Can the former client consent? A: Yes, through informed consent confirmed in writing.

Background and rules framework

Rule 4-1.9(a) governs the lawyer, Rule 4-1.10(a) imputes the conflict, and Rules 4-1.10(c) and 4-1.7 govern waiver.

Citations and references

• Missouri Rules 4-1.7, 4-1.9(a), 4-1.10(a), and 4-1.10(c)

See also

• Texas Ethics Op. 598: Lateral-Hire Imputed Conflict
• Missouri Informal Op. 2020-20: Of-Counsel Imputed Conflicts

Source

• Landing page: Missouri Informal Opinion 2017-07

Original opinion text

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

Question: Does Attorney have a conflict of interest in joining a firm that represents Client B, where Client B has interests adverse to Client A represented by Attorney’s current firm, while Attorney has not entered an appearance on behalf of Client A, and Attorney did not handle Client A’s matter on a day-to-day basis or communicate with Client A, but Attorney represented Client A at depositions and filed motions on behalf of Client A?

Answer: Because Attorney has represented Client A, Rule 4–1.9(a) governs Attorney’s duty to Client A after Attorney leaves the firm representing Client A and joins the firm representing Client B. Rule 4–1.9(a) prohibits Attorney from representing Client B in the same or substantially related matter in which Client B’s interests are materially adverse to those of Client A unless Client A gives its informed consent, confirmed in writing. Unless Client A gives that consent, Attorney’s conflict of interest will be imputed to the other lawyers at the new firm by Rule 4–1.10(a). Missouri does not recognize screening under Rules 4–1.10 or 4–1.9. The new firm’s disqualification may be waived by Client A under the conditions stated in Rule 4–1.7. See Rule 4–1.10(c).