LACBA May 27, 2026

When does a California lawyer need informed written consent to jointly represent two or more clients in the same matter?

Short answer: The opinion concludes that informed written consent under Rule 1.7(b) is generally required to jointly represent multiple clients, because joint representations normally carry a significant risk the lawyer's duties to one client will materially limit the representation of another, and that Rule 1.7(b) did not change the consent obligation that existed under former rule 3-310(C).

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This page answers the general question as of 2026. Ezel answers yours: whether it's allowed on your facts, under the current California Rules of Professional Conduct, with citations.

Disclaimer: Advisory only. Not binding precedent.
About this page: The plain-English summary, reader guidance, and Q&A below were written by Ezel based on the official ethics opinion. The original opinion (linked on this page as a PDF) is the authoritative source for any reliance.
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Plain-English summary

The committee addressed when a lawyer must obtain clients' informed written consent under California Rule of Professional Conduct 1.7(b) before accepting a joint representation of multiple clients in the same matter, and whether California's 2018 adoption of Rule 1.7(b) changed the obligation that existed under the former rules. Rule 1.7(b) bars representing a client, without informed written consent from each affected client, when there is a "significant risk" the representation will be "materially limited" by the lawyer's responsibilities to or relationships with another client. The committee concluded that because the situations giving rise to such risk arise so frequently, informed consent to a joint representation is generally required.

To define "materially limited," the committee framed the analysis around four duties a lawyer owes each client: confidentiality (Bus. & Prof. Code section 6068(e), cross-referenced in Rule 1.6); client autonomy and the duty to inform (Rule 1.4 and section 6068(m)); undivided loyalty and independent judgment; and competence (Rule 1.1). A material limitation exists at least when the lawyer cannot concurrently fulfill all duties to one joint client because of conflicting duties owed to another. For "significant risk," the committee treated the standard as prospective and objective, adopting the approach of D.C. Bar Op. 265 (1996): a conflict requiring waiver arises if an objective observer can identify and describe concrete ways one representation may reasonably be anticipated to interfere with the other; the mere possibility of future harm is not enough.

The committee identified a non-exclusive list of six potential conflict situations that could arise in most joint representations (conflicting instructions, conflicting objectives, antagonistic positions, inconsistent confidentiality expectations, a preexisting relationship with one client, and conflicting demands for an original non-electronic document or file after the representation ends). It concluded there is normally a significant risk that one of these or some other conflict could arise, so lawyers normally should comply with Rule 1.7(b) before accepting a joint representation, while recognizing exceptions such as answering a single general question or representing a company and its sole owner. Finally, the committee concluded that Rule 1.7(b), effective November 1, 2018, made no substantive change from former rule 3-310(C)(1) and (2), so appellate decisions and advisory opinions issued under the prior rule remain valid.

In practice

Under this opinion, a California lawyer asked to represent two or more clients in the same matter should, in most cases, obtain each client's informed written consent under Rule 1.7(b) before accepting the engagement, because the committee views the significant-risk threshold as normally met in joint representations. The opinion holds that the test is whether an objective observer can identify concrete ways the representation of one client may reasonably be anticipated to interfere with the lawyer's duties to another, and it treats the company-and-sole-owner situation and a single, general, easily answered question as examples that may not cross that threshold. The opinion also holds that authorities decided under former rule 3-310(C) continue to govern, and it points to LACBA Opinion 471 (1992) for the courses of action available once a material limitation exists.

Common questions

Q: Does a California lawyer always need consent to represent two clients in one matter?

A: The committee concluded informed written consent under Rule 1.7(b) is generally required, because joint representations normally present a significant risk of a material limitation, though some narrow situations do not cross that threshold.

Q: What does "materially limited" mean?

A: The committee explained it is met at least when the lawyer cannot concurrently fulfill all four duties owed to each client (confidentiality, the duty to inform, loyalty, and competence) because of conflicting duties to another joint client.

Q: When is a risk "significant" enough to require consent?

A: The committee adopted an objective, prospective test from D.C. Bar Op. 265: a waiver is required if an objective observer can identify and describe concrete ways one representation may reasonably be anticipated to interfere with the other; a mere possibility of harm is not enough.

Q: Are there joint representations that do not require consent?

A: The committee gave two examples: answering a single, general, easily answered question without one client's confidential information, and representing a company together with its sole owner.

Q: Did the 2018 adoption of Rule 1.7(b) change the consent obligation?

A: The committee concluded no; Rule 1.7(b) made no substantive change from former rule 3-310(C)(1) and (2), so prior California decisions and advisory opinions remain in effect.

Background and rules framework

The opinion interprets California Rule of Professional Conduct 1.7(b) (significant risk of material limitation) and 1.7(d) (conditions for consent), drawing on the duties in Rules 1.1 (competence), 1.2 (scope), 1.4 (communication), and 1.6 (confidentiality), and Business and Professions Code section 6068(e) and (m). It compares Rule 1.7(b) to former rule 3-310(C)(1) and (2). These correspond to ABA Model Rule 1.7 (conflicts of interest), Model Rule 1.6 (confidentiality), and Model Rule 1.1 (competence).

Citations and references

Rules of Professional Conduct:

  • California Rules 1.7(b), 1.7(d), 1.1, 1.2, 1.4, 1.6; former rule 3-310(C)(1) and (2) (applied in the opinion)
  • MR 1.7 (conflicts); MR 1.6 (confidentiality); MR 1.1 (competence)

Statutes:

  • California Business and Professions Code section 6068(e) and (m)

Cases:

  • Anderson v. Eaton (1930) 211 Cal. 113, duty of undivided loyalty
  • Havasu Lakeshore Invs., LLC v. Fleming (2013) 217 Cal. App. 4th 770, conflicts and "significant risk"
  • In re Celine R. (2003) 31 Cal.4th 45; Walker v. Apple, Inc. (2016) 4 Cal. App. 5th 1098, material and adverse effect standard

Other opinions cited:

  • Cal. State Bar Formal Ops. 1999-153, 2019-197, 2021-206: joint representation and conflicts
  • D.C. Bar Op. 265 (1996): the objective test for a "significant risk"
  • LACBA Formal Ops. 471 (1992), 529 (2017): joint-representation conflicts and confidentiality

See also

Source

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