Can a lawyer keep suing a company that briefly became a former client when another firm lawyer represented it in an unrelated case?

Plain-English summary

Lawyer Bob represented Business A against Business B in an earnest-money dispute over property contamination. Separately, Lawyer Pete, in the same medium-size firm, was asked by a long-time insurance-carrier client to represent Business B in an unrelated slip-and-fall case. The two cases had no similarities, and the two lawyers had not discussed the merits, strategies, or any confidential information about Business B. On discovering the potential conflict, Lawyer Pete terminated the firm's representation of Business B with no prejudice to its interests. The question was whether the rules barred Lawyer Bob from continuing to represent Business A against Business B, now a former client.

The committee concluded they did not. Assuming the representation of Business B was terminated ethically under Rule 1.16, Rule 1.9(a) governed: a lawyer who has formerly represented a client may not later represent another person in the same or a substantially related matter with materially adverse interests unless the former client consents. The rule sets no standard tied to the type or length of the former representation, and while the duty to preserve confidences survives, there is no duty of continued representation. The only relevant question was whether the suit between Business A and Business B was substantially related to the former representation of Business B. Applying its two tests (whether the relationship between issues is "patently clear" and whether the lawyer could have acquired related information during the former representation, citing Advisory Opinion 90-34), the committee found the matters not substantially related under either approach. Lawyer Bob was therefore not required to discontinue his representation of Business A.

Currency note

This opinion was issued in 1993, before the South Carolina Bar's adoption of the 2005 revisions to the Rules of Professional Conduct. 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 Treat this page as historical context, not current guidance.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 sue a former client without that client's consent?

A: Yes, where the new matter is not the same or substantially related to the former representation. The committee read Rule 1.9(a) to require consent only when the matters are the same or substantially related and interests are materially adverse.

Q: How did the committee decide the matters were not substantially related?

A: It used two tests from Advisory Opinion 90-34: whether the relationship between the issues is "patently clear," and whether the lawyer could have acquired related information during the former representation. Neither was met here.

Q: Did the brief, unrelated representation create an ongoing duty to Business B?

A: No. The committee said the duty to preserve confidences survives, but there is no duty of continued representation; the attorney-client relationship ends when the matter is resolved.

Background and rules framework

The opinion applied Rule 1.9(a) (duties to former clients) and assumed proper termination under Rule 1.16 (declining or terminating representation), which correspond to like-numbered Model Rules. Rule 1.9(a) turns on whether the new matter is the same as or substantially related to the former representation and whether interests are materially adverse.

Citations and references

Rules of Professional Conduct:

• South Carolina RPC 1.9(a) / Model Rule 1.9(a): a lawyer who formerly represented a client shall not represent another in the same or a substantially related matter with materially adverse interests, absent the former client's consent.
• South Carolina RPC 1.16 / Model Rule 1.16: declining or terminating representation.

Other opinions cited:

• SC Bar Advisory Opinion 90-34 (substantial-relationship tests); SC Bar Advisory Opinion 88-19.

See also

• SC Bar Ethics Op. 93-23: Advance Consent for a Lender's Lawyer
• SC Bar Ethics Op. 05-13: Suing a Former Firm
• SC Bar Ethics Op. 00-05: Past Closings, Later Divorce

Source

• Landing page: https://www.scbar.org/for-lawyers/quicklinks/legal-resources/ethics-advisory-opinions/ethics-advisory-opinion-93-19/

Original opinion text

Reproduced from the official source for research purposes. The linked source is authoritative.

UPON THE REQUEST OF A MEMBER OF THE SOUTH CAROLINA BAR, THE ETHICS ADVISORY COMMITTEE HAS RENDERED THIS OPINION ON THE ETHICAL PROPRIETY OF THE INQUIRER’S CONTEMPLATED CONDUCT. THIS COMMITTEE HAS NO DISCIPLINARY AUTHORITY. LAWYER DISCIPLINE IS ADMINISTERED SOLELY BY THE SOUTH CAROLINA SUPREME COURT THROUGH ITS COMMISSION ON LAWYER CONDUCT.

Ethics Advisory Opinion 93-19

Facts:
Lawyer Bob of medium size law firm represents long time client Business "A" in an action against Business "B" involving the purchase of property and the return of earnest money because of environmental contamination of the property to be purchased.

Subsequently, Lawyer Pete of medium size law firm, at the request of long time client insurance carrier, represented Business "B" in a "slip and fall action" filed by individual plaintiff.

The cases have no similarities. Lawyer Bob and Lawyer Pete have not discussed the merits of the cases nor the strategies of the defenses nor confidential information about Business "B".

Upon discovering the potential conflict, Lawyer Pete terminated his representation of Business "B" with no resulting prejudice to the interest of Business "B".

Question:
Do the Rules of Professional Conduct prohibit Lawyer Bob from continuing his representation of Business "A" against Business "B", now a former client?

Summary:
A lawyer may represent a client in an action against a former client without the former client's consent where, as here, the contested matter is not the same or substantially related.

Opinion:
The following opinion assumes the representation of Business "B" was "terminated" in an ethical manner pursuant to Rule 1.16.

Rule 1.9(a) of the SC Rules of Professional Conduct clearly sets forth the guideline for representation against former clients:

A lawyer who has formerly represented a client in a matter shall not thereafter represent another person in the same or a substantially related matter in which that person's interests are materially adverse to the interests of the former client unless the former client consents after consultation.

This rule sets forth no standards regarding the type or length of representation of the former client, but applies uniformly to all clients formerly represented. While an attorney's ethical duty of preserving client confidences continues after severance of the attorney-client relationship, the attorney owes no duty of continued representation. The attorney-client relationship is severed once the case is terminated or the matter resolved. See Advisory Opinion 88-19.

The Comment to Rule 1.9 provides guidance in the present case by stating that "a lawyer who recurrently handled a type of problem for a former client is not precluded from later representing another client in a wholly distinct problem of that type even though the subsequent representation involves a position adverse to the prior client". The Comment defines the question as "whether the lawyer so involved in the matter that the subsequent representation can be justly regarded as a changing of sides in the matter in question."

The only relevant issue posed by these facts is whether the suit between Business "A" and Business "B" is one substantially related to the former representation of Business "B". The Committee has relied upon two tests to determine whether matters are "substantially related" for the purposes of Rule 1.9:
1) whether the relationship between issues in the prior and present case are "patently clear"; and
2) whether, during the former representation, an attorney could have acquired information related to the subject matter of the new representation.

See Advisory Opinion 90-34. Under neither approach is the representation of Business "A" substantially related to the former representation of Business "B".

Lawyer Bob is not required to discontinue his representation of Business "A" against his former client, Business "B".