Ezel / Ethics Opinions / NYSBA
NYSBA 1992-03-19

Can a lawyer sue a former client when the new matter is unrelated, and does the recency of the prior representation matter?

Short answer: The opinion concluded that a lawyer may represent a plaintiff against a former client unless the matters are substantially related or the lawyer holds relevant confidences; the duty of loyalty ends when the representation does, so the recency of the prior matter alone is not disqualifying.
Currency note: this opinion is from 1992
Subsequent statutory amendments, court decisions, or later opinions or rule amendments may have changed the analysis. Treat this page as historical context, not current legal advice. Verify current law before relying on any specific rule, deadline, or remedy mentioned here.
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 Not binding precedent.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 at the bottom of this page) is the authoritative source for any reliance.

NY State Bar Ethics Opinion 628: Suing a former client in an unrelated matter

Short answer: The opinion concluded that a lawyer may represent a plaintiff against a former client unless the prior matter is substantially related to the new one or the lawyer obtained relevant confidences or secrets in the prior representation; because the duty of loyalty ends when the representation does and only the duty of confidentiality continues, the mere recency of the prior matter does not disqualify the lawyer.

Disclaimer: This is an advisory ethics opinion. Advisory opinions are not binding; they interpret the New York State Bar Association's rules of professional conduct and are persuasive authority. This summary is for research purposes only and is not legal advice. Verify current rules before acting on any specific guidance.

About this page: The plain-English summary and Q&A below were written by Ezel based on the official opinion. We do not reproduce the opinion text on this page; follow the linked source for the official text, which controls.

View original opinion

Plain-English summary

A lawyer had defended a restaurant in Small Claims Court about a year earlier in a case over items stolen from a car in the restaurant's parking lot. He now wanted to represent an individual who fell and broke her hip at the same restaurant, in a tort action against it. He believed the two matters were unrelated and that he had learned nothing useful to the new case.

The committee applied DR 5-108 ("Conflict of Interest - Former Client"), added to the New York Code effective September 1, 1990 and patterned on Model Rule 1.9. Under DR 5-108(A), absent the former client's consent after full disclosure, a lawyer may not represent another person in the same or a substantially related matter with materially adverse interests, or use the former client's confidences or secrets. The committee adopted DR 5-108(A)'s textual standard as the disciplinary test, distinguishing it from the judicially developed "substantial relationship" test that governs disqualification motions, which is keyed to whether litigation would be "tainted." On the facts, the committee agreed the parking-lot theft case was not substantially related to a slip-and-fall case; knowing the former client's financial or corporate structure was not itself disqualifying unless that background was at issue in the new matter.

The committee rejected any temporal or recency element. It held that the duty of undivided loyalty, which controls in simultaneous representation, ends with the lawyer-client relationship; what survives is the duty to preserve the former client's confidences and secrets, whether actual (DR 5-108(A)(2)) or presumed in substantially related matters (DR 5-108(A)(1)). It also addressed consent. The former client's consent can cure the conflict. But if the former client consents to the representation yet insists that confidences be kept, and preserving them may impair the lawyer's judgment for the new client, DR 5-101(A) requires the current client's informed consent too, and the committee noted that in the typical case the lawyer cannot make the disclosure needed for that consent without revealing the protected confidences, so the consent often cannot practicably be obtained (citing ABA Formal Op. 90-358).

Currency note

This opinion was issued in 1992, under New York's former Code of Professional Responsibility, which New York replaced with the Rules of Professional Conduct in 2009. The former-client provisions cited here have since been recast in Rule 1.9. Subsequent rule amendments or later opinions may have changed the analysis. Treat this page as historical context, not current guidance. Verify against current rules before relying on any specific rule, deadline, or requirement mentioned here.

Common questions

Q: Can a lawyer take a case against a former client?

A: Yes, unless the new matter is the same as or substantially related to the prior one with materially adverse interests, or the lawyer holds relevant confidences or secrets of the former client; otherwise DR 5-108(A) does not bar the representation.

Q: Does it matter that the prior representation ended only recently?

A: No. The committee rejected a temporal element, holding that the duty of loyalty ends with the representation and only the duty to preserve confidences and secrets survives, so recency alone is not disqualifying.

Q: Is knowing a former client's finances enough to disqualify the lawyer?

A: No, not by itself. The committee held that general knowledge of a former client's financial or corporate structure is not disqualifying unless that background is at issue in the new litigation.

Q: When is the current client's consent also needed?

A: When the former client consents but insists confidences be kept, and that duty may impair the lawyer's judgment, DR 5-101(A) requires the current client's informed consent; the committee noted that consent often cannot practicably be obtained because the disclosure needed would reveal the protected confidences.

Background and rules framework

The opinion interpreted DR 5-108 (former-client conflicts), with DR 4-101 (confidences and secrets), DR 5-101(A) (a lawyer's own interests, including duties to third parties, affecting judgment), DR 5-105, and Canon 9. DR 5-108 was patterned on Model Rule 1.9. The closest Model Rule analogues are Rule 1.9 (duties to former clients), Rule 1.6 (confidentiality), and Rule 1.7 (current-client conflicts and informed consent).

Citations and references

Rules of Professional Conduct:

  • MR 1.9 (duties to former clients)
  • MR 1.6 (confidentiality of information)
  • MR 1.7 (concurrent conflicts of interest)
  • NY DR 5-108; DR 4-101; DR 5-101(A); DR 5-105; Canon 9

Cases:

  • T.C. Theatre Corp. v. Warner Bros. Pictures, 113 F. Supp. 265 (S.D.N.Y. 1953): substantial-relationship test and the scope of a surviving duty to a former client
  • Evans v. Artek Systems Corp., 715 F.2d 788 (2d Cir. 1983): disqualification keyed to litigation taint

Other opinions cited:

  • ABA Formal Op. 90-358 (1990): when the current client's consent cannot practicably be obtained
  • N.Y. State 605 (1989): substantial-relationship test in successive criminal representation

See also

Source