Summary
Lawyers engaging in mediation have ethical obligations, whether they are advocates representing clients or third-party neutrals facilitating settlement. These obligations derive from statutes, regulations, and other sources such as American Bar Association (ABA) Model Rules and Formal Opinions and Model Standards of Conduct for Mediators, adopted by the American Arbitration Association, ABA Section of Dispute Resolution, and Association for Conflict Resolution. Generally, lawyer advocates owe duties of competence, diligence, and communication to their clients and may engage in overstatements to advance client interests. In contrast, lawyer mediators must be neutral, communicating that they do not provide legal advice or act in a party’s best interests. Even if not lawyers, mediators are expected to abide by ethical parameters.
ABA Formal Opinion 518 Spotlights Mediation Ethics
On October 15, 2025, the American Bar Association (ABA) Standing Committee on Ethics and Professional Responsibility issued Formal Opinion 518 - A Lawyer’s Duties to Avoid Misleading Communications When Acting as a Third-Party Neutral Mediator. Directed to third-party neutrals, the Opinion also has implications for lawyer advocates. Further, the Opinion and Model Rules it discusses do not apply to mediators who are not lawyers, but it is instructive for all neutrals. They provide a foundation, but there are additional sources of ethical guidance.
The Opinion advises that lawyer mediators must: (1) not represent parties in mediation and cannot provide legal advice to participants; (2) ensure unrepresented parties and parties unfamiliar with mediation understand the neutral’s role; and (3) refrain from statements involving dishonesty, fraud, deceit, or misrepresentation.
ABA Model Rules, discussed in the Opinion, provide a template on which individual jurisdictions promulgate rules governing lawyer conduct. Lawyers should consult the rules applicable to them. Regardless of profession, mediators should also be aware of the Model Standards of Conduct for Mediators, adopted by the American Arbitration Association, ABA Section of Dispute Resolution, and Association for Conflict Resolution. Mediators should also be knowledgeable about other applicable rules.
Lawyer Advocate Ethical Duties to Clients in Mediation
Formal Opinion 518 emphasizes that a mediator’s duty is to remain neutral towards all parties, in contrast with an advocate’s duties to the clients they represent in mediation. A lawyer owes clients duties of care, including Model Rules 1.1 (Competence), 1.3 (Diligence), and 1.4 (Communications), that are not implicated when a lawyer serves as a mediator.
Rule 1.1 states: “A lawyer shall provide competent representation to a client. Competent representation requires legal knowledge, skill, thoroughness, and preparation reasonably necessary for the representation.” (Italics added.) Rule 1.3 provides: “A lawyer shall act with reasonable diligence and promptness in representing a client.” (Italics added.) Rule 1.4 provides in part:
(a) A lawyer shall:
(1) promptly inform the client of any decision or circumstance with respect to which the client's informed consent, …;
(2) reasonably consult with the client about the means by which the client's objectives are to be accomplished;
(3) keep the client reasonably informed about the status of the matter; …
(b) A lawyer shall explain a matter to the extent necessary to permit the client to make informed decisions regarding the representation. (Italics added.)
Lawyers owe duties of competence, diligence, and communication to their clients. For advocates, competence includes selecting a mediator with the right experience and temperament for clients in the particular case, and assuring the selected mediator fulfils their ethical obligations. Advocates should ensure that clients understand the mediator’s unbiased role, so clients do not have unrealistic expectations or expect the mediator to be protecting them. Diligence requires advocates not to abdicate their responsibilities to clients. They should not enlist a mediator to convince a client that a settlement is in the client’s best interests. Communicating with clients about the merits of a resolution falls on the advocate and is beyond the mediator’s purview.
The mediator’s professional responsibilities do not derive from a lawyer-client relationship. They derive from Rule 2.4 (Lawyer Serving as Third-Party Neutral), which provides:
(a) A lawyer serves as a third-party neutral when the lawyer assists two or more persons who are not clients of the lawyer to reach a resolution of a dispute or other matter that has arisen between them. Service as a third-party neutral may include service as an arbitrator, a mediator, or in such other capacity as will enable the lawyer to assist the parties to resolve the matter.
(b) A lawyer serving as a third-party neutral shall inform unrepresented parties that the lawyer is not representing them. When the lawyer knows or reasonably should know that a party does not understand the lawyer's role in the matter, the lawyer shall explain the difference between the lawyer's role as a third-party neutral and a lawyer's role as one who represents a client. (Italics added).
Mediators, whether or not they are lawyers, may also be bound by the Model Standards, including Self-Determination, Impartiality, Conflicts of Interest, (Competence), and Quality of Process. “Self-Determination is the act of coming to a voluntary, uncoerced decision in which the party makes free and informed choices as to process and outcome.” Standard I(A). “Impartiality means freedom from favoritism, bias or prejudice.” Standard II(a). “A lawyer should avoid a conflict of interest or the appearance of a conflict of interest during and after a mediation.” Standard III(A). Competence requires that a mediator “only mediate when the mediator has the necessary competence to satisfy the reasonable expectations of the parties.” Standard IV(A). The obligation to ensure the Quality of the Process requires the mediator to abide by the Model Standards. Standard IV(A).
Mediators should ensure all parties, even those represented by counsel, understand that the mediator is nonaligned. The mediator must communicate that they will not provide parties with legal advice or act to protect a party’s interests. The mediator should ensure parties have sufficient opportunity to probe the parameters of a mediator’s role. These constraints do not preclude the mediator from sharing an opinion on legal issues or on how a tribunal might rule. However, the mediator should not encourage a party to accept a deal. Assessment of how a case might result should be done by counsel. If a party is unrepresented, the mediator cannot advise them other than to urge the party to seek independent legal advice. Even if a mediator is not a lawyer, as Standard VI (A)(10) provides, “If a party appears to have difficulty comprehending the process, issues, or settlement options, or difficulty participating in a mediation, the mediator should explore the circumstances and potential accommodations.”
Ethical Duties of Avoiding Misconduct
Formal Opinion 518 highlights ethical issues surrounding mediator communication with parties. Lawyer advocates have leeway on what they communicate compared to communications made by the neutral. Model Rule 8.4 (Misconduct) applies to lawyers as counsel and as neutral, providing in part:
It is unprofessional misconduct for a lawyer to:
(a) violate or attempt to violate the Rules of Professional Conduct, knowingly assist, or induce another to do so, or do so through the acts of another; …
(c) engage in conduct involving dishonesty, fraud, deceit, or misrepresentation; …. (Italics added.)
Rule 8.4 is not limited to advocates or mediators, but the rule’s application differs depending on the hat a lawyer is wearing. For example, Rule 4.1 (Truthfulness in Statements to Others), which applies to advocates and not to mediators, highlights the different expectations of lawyers in each role. It provides in part, “In the course of representing a client a lawyer shall not knowingly (a) make a false statement of material fact or law to a third person; … (italics added). Comment [2] to Rule 8.4 states:
This Rule refers to statements of fact. Whether a particular statement should be regarded as one of fact can depend on the circumstances. Under generally accepted conventions in negotiation, certain types of statements ordinarily are not taken as statements of material fact. Estimates of price or value placed on the subject of a transaction and a party’s intentions as to an acceptable settlement of a claim are ordinarily in this category, and so is the existence of an undisclosed principal except where nondisclosure of the principal would constitute fraud. Lawyers should be mindful of their obligations under applicable law to avoid criminal and tortious misrepresentation.
An advocate may take liberties in negotiations, including how they characterize a client’s likelihood of success or receptivity to settlement. Counsel representing a client may engage in puffery, express opinions, or issue ultimatums in mediation, and such statements are not considered material factual misstatements. A lawyer representing a client in mediation does not violate Rule 8.4 by making negotiation-type statements to advance the client’s interests.
A mediator does not have the same license. They must be disciplined in how and what they communicate. Comment [2] to Rule 8.4 does not shield mediators who engage in negotiation tactics invoked by advocates. Formal Opinion 518 condemns “exaggeration or concealment” as a strategy for mediators to persuade parties to reach an agreement. Parties expect that the mediator is impartial, and any statements they make are credible. Lawyer mediators must avoid conveying information that could be interpreted as material fact when the mediator doubts the veracity. Neutrality requires a mediator to refrain from urging a party to accept an offer as being in their best interests. Assessing whether a proposal is best for a party should be made by the party in consultation with their counsel. Even for non-lawyer mediators, these boundaries make sense. As Model Standard I (A)(2) Self-Determination states, “where appropriate, a mediator should make the parties aware of the importance of consulting other professionals to help them make informed choices.” In addition, Standard VI(A)(10) requires a mediator to “promote honesty and candor between and among all participants, and a mediator shall not knowingly misrepresent any material fact or circumstance in the course of a mediation.”
Ethical Duties if a Deal is Reached
If parties reach a resolution during mediation, before the parties adjourn, attorneys should prepare a memorandum of understanding, if not a full agreement. An advocate should discuss with the client the desired terms of a deal beyond merely discussing numbers. Counsel should come prepared with a checklist of terms to be included and be ready to memorialize the deal. This is consistent with counsel’s ethical duties of competence, diligence, and communication.
The mediator does not have the same role here. Generally, mediators should not comment on settlement terms; that is the purview of the advocates. Mediator input on papering the deal crosses the line. Standard III (a) states, “A conflict of interest can arise from involvement by a mediator with the subject matter of the dispute or from any relationship between a mediator and any mediation participant, whether past or present, personal or professional, that reasonably raises a question of a mediator’s impartiality.” When the mediator injects themselves in crafting or memorializing terms, the mediator can create an actual conflict or appearance of conflict, as the input could be perceived as favoring one party over another. Jurisdictional rules may vary as to where the mediator must draw the line with respect to memorializing settlement terms.
Conclusion
The Model Rules and ABA Formal Opinion 518 provide guidance on the professional responsibility of lawyers in mediation, whether serving as client representatives or neutral facilitators. Lawyers in both capacities should consider these issues as well as any other applicable materials to remain within ethical boundaries. Mediators, whether lawyers or not, should also consider the Model Standards in their neutral practice, as well as additional ethical requirements based on forum or governing bodies.