ABA Model Rules 1.7, 1.9 & 1.10: Conflicts, Waivers, Imputation

ABA Model Rules 1.7, 1.9, and 1.10 govern conflicts of interest for American lawyers: Rule 1.7 restricts taking on work that clashes with a current client, Rule 1.9 restricts working against a former client in a related matter, and Rule 1.10 treats every lawyer in a firm as one unit so that one lawyer’s disqualification usually disqualifies the whole firm. Every state has adopted some version of these rules, though the details vary.¹ Together they define what “loyalty” means in practice, and they follow lawyers across matters, firms, and careers.

Rule 1.7: Conflicts With Current Clients

Rule 1.7 recognizes two kinds of concurrent conflict. The first is direct adversity. You represent Client A, and now you want to represent Client B in a matter where B’s interests are opposed to A’s.¹ Whether the two matters are related does not matter. A lawyer who represents a company in a real estate deal cannot simultaneously sue that same company on behalf of a different client in a personal injury case. In Cinema 5, Ltd. v. Cinerama, Inc., the Second Circuit held that where the attorney-client relationship is ongoing, adverse representation is presumptively improper, and the attorney bears the burden of showing that no actual or apparent conflict will result.²

The second category is material limitation. Nobody is suing anyone else’s client, but the lawyer’s ability to give full-throated advice is constrained by obligations to another client, a former client, a third party, or the lawyer’s own interests.¹ A lawyer negotiating a contract for one client might pull punches on a particular term because pushing hard would hurt a different client’s business. A lawyer with a significant financial stake in a client’s competitor might unconsciously shade advice. These conflicts are harder to spot than direct adversity, which is exactly what makes them dangerous.

Criminal defense is where concurrent conflicts get their sharpest teeth. When two co-defendants share a lawyer, one may benefit from cooperating with prosecutors and testifying against the other. A single lawyer cannot advocate for both people in that situation. Multiple federal circuits require trial judges to conduct an affirmative on-the-record inquiry, advising jointly represented defendants of the risks and confirming that each knowingly waives the right to unconflicted counsel.³

When a Client Can Waive a 1.7 Conflict

Many concurrent conflicts are waivable. Under Rule 1.7(b), a lawyer can proceed despite a conflict if four conditions are satisfied: the lawyer reasonably believes competent and diligent representation is still possible; the representation is not prohibited by law; it does not involve one client asserting a claim against another client of the same lawyer in the same proceeding; and every affected client gives informed consent, confirmed in writing.¹

“Informed” is doing a lot of work in that sentence. Handing the client a form to sign is not enough. The lawyer must explain the specific risks and realistic alternatives clearly enough that the client actually understands what they are agreeing to.

Some conflicts cannot be waived no matter what the client says. When one client is asserting a claim against another current client of the same lawyer in the same litigation, consent will not cure the problem.¹ And if no reasonable lawyer would conclude that the representation could be handled competently despite the conflict, a signed waiver is meaningless. The test is not whether the client wants to proceed; it is whether competent advocacy is realistically achievable.

Advance Waivers

Sophisticated clients, especially large corporate clients with long-standing outside counsel relationships, sometimes sign advance waivers consenting to conflicts that have not yet arisen. These can be valid, but with real limits. Open-ended waivers attempting to cover any future conflict of any kind are generally unenforceable. To hold up, an advance waiver should be limited in scope, preceded by meaningful disclosure of the reasons for the waiver and its potential downsides, and should not extend to substantially related matters unless the conflict arises between jointly represented clients. Clients experienced in legal matters and independently represented are far more likely to produce enforceable advance waivers than unsophisticated individuals.

Revoking Consent

A client who previously consented to a conflict can revoke that consent at any time. But revocation does not automatically force the lawyer to stop representing other clients who relied on the original consent. Whether the lawyer must withdraw depends on the nature of the conflict, whether the revocation was prompted by a material change in circumstances, the reasonable expectations of the other clients, and whether continuing would cause material detriment to anyone involved.⁴ This is why the initial consent conversation matters so much. If the lawyer never explained the possibility, a later revocation can create a mess with no clean resolution.

You Can’t Drop a Client to Escape a Conflict

When a lawyer discovers a concurrent conflict between two current clients, the tempting move is to drop the less lucrative client and keep the bigger one. Courts have consistently rejected that maneuver under what has become known as the “hot potato” doctrine, which traces to Picker International, Inc. v. Varian Associates, Inc. A firm cannot drop a client like a hot potato to take on more profitable work adverse to that client. Once the attorney-client relationship exists, the lawyer cannot escape the concurrent-conflict analysis simply by firing one client. The only clean exits are informed consent from all affected clients or a genuine withdrawal for reasons unrelated to the new engagement.

Rule 1.9: Conflicts With Former Clients

Loyalty does not end when the representation does. Under Rule 1.9, a lawyer who previously represented a client in a matter cannot later represent someone else in the same or a substantially related matter if the new client’s interests are adverse to the former client’s, unless the former client gives informed written consent.⁵

The phrase “substantially related” is the heart of the rule. The landmark case articulating it is T.C. Theatre Corp. v. Warner Bros. Pictures, where the court held that when a former client shows the new matter is substantially related to the old one, the court will presume confidential information was shared during the prior representation. The former client does not have to prove what was actually disclosed.⁶ If a lawyer handled a company’s internal tax audits, that lawyer cannot later represent a whistleblower suing the same company for tax fraud. The factual overlap is obvious, and the court will not require the former client to detail exactly which confidences were shared.

Rule 1.9 also restricts lawyers who change firms. If your old firm represented a client, you cannot represent someone adverse to that client in a related matter at your new firm, provided you personally acquired confidential information material to the matter. And regardless of whether you switch sides, you can never use or reveal a former client’s confidential information to their disadvantage. That prohibition applies permanently, with no expiration date.⁵

Rule 1.10: One Lawyer’s Conflict Is the Firm’s Conflict

Rule 1.10 treats every lawyer in a firm as a single unit for conflict purposes. If one lawyer is personally disqualified from a matter under Rule 1.7 or 1.9, every other lawyer at the firm is also disqualified.⁷ The rationale is straightforward. Lawyers in the same firm share information and share a common financial interest, so a wall of good intentions between one lawyer’s desk and another’s is not trustworthy enough on its own.

Two exceptions matter. First, when the disqualified lawyer’s conflict is purely personal, such as a financial interest or a family connection, and it does not meaningfully risk limiting the other lawyers’ representation, the firm is not automatically disqualified.⁷ Second, when the conflict stems from a lawyer’s work at a previous firm, screening can save the new firm from disqualification. The requirements for that screen are exacting:

The disqualified lawyer must be blocked from any participation in the matter and cannot receive any portion of the fee from it.
The firm must promptly notify the affected former client in writing, describing the screening procedures and confirming both the firm’s and the screened lawyer’s compliance.
At the former client’s written request, both the screened lawyer and a firm partner must provide certifications of compliance at reasonable intervals and when the screening ends.⁷

When a conflicted lawyer leaves a firm entirely, the remaining lawyers are not automatically free to take adverse work either. They can proceed only if the departed lawyer’s matter is not substantially related to the new one, or if no remaining lawyer holds confidential information material to the case.⁷

What Happens When These Rules Are Violated

The most immediate consequence of a conflict violation is disqualification from the case. A court that finds an unwaived conflict will remove the lawyer, and often the entire firm, from the matter. For the affected client, that means finding new counsel, bringing them up to speed, and absorbing the delay and expense of starting over.

The financial hit for the disqualified lawyer is often worse than losing the case. The general rule is that a lawyer disqualified for violating an ethical obligation is not entitled to any fees for services rendered in that matter. The forfeiture applies to the entire engagement, not just a portion of it.

Disciplinary consequences run separately, ranging from private admonishment to suspension or disbarment, depending on the severity of the conflict, whether the lawyer acted knowingly, and whether clients were actually harmed. Academic research has noted that disciplinary systems tend to under-enforce conflict violations, particularly when no disqualification motion brings the conflict to a court’s attention.

Malpractice liability is a third track. A client who suffers harm because their lawyer was operating under a conflict can sue for damages, and fee forfeiture can be pursued as an independent cause of action without proof of the traditional malpractice elements like causation and damages. In large commercial disputes, the exposure for a firm can be enormous.

1
American Bar Association. Rule 1.7 Conflict of Interest Current Clients
2
Justia. Cinema 5 Ltd. v. Cinerama, Inc.
3
Hofstra Law Review. Joint Representation of Multiple Defendants in a Criminal Trial
4
American Bar Association. Rule 1.7 Conflict of Interest Current Clients – Comment
5
American Bar Association. Rule 1.9 Duties to Former Clients
6
Justia. T.C. Theatre Corp. v. Warner Bros. Pictures, 113 F. Supp. 265 (S.D.N.Y. 1953)
7
American Bar Association. Rule 1.10 Imputation of Conflicts of Interest General Rule