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February 10, 2021

ABA issues new guidance on definition of ‘material adverseness’ in client representation

CHICAGO, Feb. 10, 2021 — The American Bar Association Standing Committee on Ethics and Professional Responsibility released today a formal opinion explaining when ABA model rules prohibit a lawyer from representing a new client against the interests of a former one.

Formal Opinion 497 interprets both Rule 1.9(a) and Rule 1.18(c) of ABA Model Rules of Professional Conduct to find “material adverseness” exists when a lawyer is negotiating or litigating against a former or prospective client or attacking the work done for the former client on behalf of a current client in the same or a substantially related matter.

The formal opinion also lists other specific instances when the model rules related to “material adverseness” would apply, such as if the former client can point to some specific material legal, financial or other identifiable concrete detriment that would be caused by the current representation. “However, neither generalized financial harm nor a claimed detriment that is not accompanied by demonstrable and material harm or risk of such harm to the former or prospective client’s interests suffices,” the opinion said.

The former client can waive the conflict with informed consent, confirmed in writing, the opinion noted.

The ABA Standing Committee on Ethics and Professional Responsibility periodically issues ethics opinions to guide lawyers, courts and the public in interpreting and applying ABA model ethics rules to specific issues of legal practice, client-lawyer relationships and judicial behavior. Recent ABA ethics opinions are available on the ABA Center for Professional Responsibility.

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