What did this opinion require before suing former clients on unrelated matters?

Plain-English summary

A lawyer was representing clients in matters adverse to people the lawyer had represented at a previous firm. The new matters were unrelated to the old ones.

The opinion required the lawyer, under Rule 4-1.9(b), to determine in each case whether confidential information from the former representation could be used to the former client's detriment. It said confidentiality under Rule 4-1.6 was broader than attorney-client privilege and included any information acquired as a result of the prior representation. The published answer did not decide particular cases because it lacked their facts.

Currency note

This 1995 opinion predates Missouri's 2007 amendments to its Rules of Professional Conduct. An official reference note identifies July 1, 2007 amendments to Rules 4-1.9 and 4-1.10. Subsequent rule amendments or later opinions may have changed the analysis. Treat this page as historical context and verify current rules before relying on it.

Common questions

Q: Did unrelated subject matter end the inquiry?

A: No. The opinion still required a case-by-case confidential-information assessment.

Q: Was confidentiality limited to attorney-client privilege?

A: No. The opinion said Rule 4-1.6 reached more broadly to information obtained through the earlier representation.

Background and rules framework

The opinion applied Missouri Rule 4-1.9(b) to new work adverse to former clients and used Rule 4-1.6's broad confidentiality concept to define the information the lawyer had to consider.

Citations and references

Rules of Professional Conduct:

• Missouri Rule 4-1.9(b)
• Missouri Rule 4-1.6

See also

• Missouri Informal Op. 970082: Firm former-client conflict
• Missouri Informal Op. 960014: Joint bankruptcy client divorce

Source

• Landing page: https://mo-legal-ethics.org/informal-opinion/950199/

Original opinion text

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

QUESTION: Attorney is representing clients against former clients whom Attorney represented when Attorney was in another firm. The current matters are not related to the matters on which Attorney represented the former clients. May Attorney continue representation of the current clients? ANSWER: Under Rule 4–1.9(b) Attorney must determine, for each case, whether Attorney obtained confidential information in the course of the previous representation that could be used to the previous client´s detriment in the current case. Confidentiality under Rule 4–1.6 is much broader than the attorney-client privilege which is a statutory evidentiary rule. Any information which came into Attorney´s possession as a result of the previous representation would be included under the ambit of confidential information.