May a lawyer represent a father against a mother in custody matters after jointly representing both parents in estate and financial work?

Plain-English summary

The lawyer previously represented both parents in a financial transaction and estate planning, then proposed representing the father against the mother in custody, access, and contempt motions. The opinion identifies the mother as a former client under Rule 4-1.9.

If any pending motion is the same as or substantially related to the earlier work, Rule 4-1.9 requires the mother’s informed consent confirmed in writing. The office cannot decide whether that relationship exists without additional facts. It quotes Comment [3] on the risk that confidential information from the prior matter would materially advance the new client’s position.

Regardless of substantial relatedness, Rule 4-1.9(c) bars use or disclosure of information from the earlier representation of the mother except as the Rules would permit or require for a current client.

In practice

The opinion makes consent turn on the factual relationship between each pending custody matter and the earlier joint work. Its separate former-client confidentiality restriction applies whether or not the matters are substantially related.

Common questions

Q: When is the mother’s written consent required?

A: When any pending matter is the same as or substantially related to the prior representation of the mother, the opinion requires her informed consent confirmed in writing.

Q: Did the office decide whether the custody and estate matters are substantially related?

A: No. It says the answer requires additional facts.

Q: Can the lawyer use information from the mother’s earlier representation if the matters differ?

A: Rule 4-1.9(c) still prohibits use or disclosure except as the Rules permit or require for a client.

Background and rules framework

Rule 4-1.9 governs the proposed representation against a former client. Comment [3] supplies the substantial-relatedness standard, and Rule 4-1.9(c) independently restricts use and disclosure of former-client information.

Citations and references

Missouri Rules of Professional Conduct:

• Rule 4-1.9 and Comment [3]
• Rule 4-1.9(c)

See also

• Missouri Informal Op. 2022-01: Former-Client Information
• Missouri Informal Op. 2021-04: Failed Common Representation

Source

• Landing page: https://mo-legal-ethics.org/informal-opinion/2015-08/

Original opinion text

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

Question: May Attorney represent Father against Mother in various motions related to custody, family access, and contempt, where Attorney previously represented Mother and Father jointly in a financial transaction and for estate planning?

Answer: Mother is Attorney’s former client under Rule 4–1.9. If any one of Father’s pending matters is “the same or a substantially related matter” to any of the previous representations of Mother by Attorney, Attorney must have Mother’s informed consent, confirmed in writing, to represent Father in the matter(s). For purposes of Rule 4–1.9, matters are substantially related “if there . . . is a substantial risk that confidential factual information as would normally have been obtained in the prior representation would materially advance the client’s position in the subsequent matter.” Comment [3]. Whether any one of the actions is substantially related to a prior matter for which Attorney represented Mother is a factual question about which an informal opinion cannot be issued without additional facts. Regardless of whether the matters are substantially related, Attorney is prohibited by Rule 4–1.9(c) from using or revealing information relating to any prior representation of Mother except as the Rules would permit or require with respect to a client.