(a) 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 gives informed consent, confirmed in writing.
(b) A lawyer shall not knowingly represent a person in the same or a substantially related matter in which a firm with which the lawyer formerly was associated had previously represented a client
(1) whose interests are materially adverse to that person; and
(2) about whom the lawyer had acquired information protected by Rules 1.6 and 1.9(c) that is material to the matter; unless the former client gives informed consent, confirmed in writing.
(c) A lawyer who has formerly represented a client in a matter or whose present or former firm has formerly represented a client in a matter shall not thereafter:
(1) use information relating to the representation to the disadvantage of the former client except as these Rules would permit or require with respect to a client, or when the information has become generally known; or
(2) reveal information relating to the representation except as these Rules would permit or require with respect to a client.
The Louisiana Supreme Court adopted this rule on January 20, 2004. It became effective on March 1, 2004, and has not been amended since. This rule is identical to ABA Model Rule of Prof’l Conduct 1.9 (2002).
Comments to ABA Model Rule 1.9
 After termination of a client-lawyer relationship, a lawyer has certain continuing duties with respect to confidentiality and conflicts of interest and thus may not represent another client except in conformity with this Rule. Under this Rule, for example, a lawyer could not properly seek to rescind on behalf of a new client a contract drafted on behalf of the former client. So also a lawyer who has prosecuted an accused person could not properly represent the accused in a subsequent civil action against the government concerning the same transaction. Nor could a lawyer who has represented multiple clients in a matter represent one of the clients against the others in the same or a substantially related matter after a dispute arose among the clients in that matter, unless all affected clients give informed consent. See Comment . Current and former government lawyers must comply with this Rule to the extent required by Rule 1.11.
 The scope of a “matter” for purposes of this Rule depends on the facts of a particular situation or transaction. The lawyer’s involvement in a matter can also be a question of degree. When a lawyer has been directly involved in a specific transaction, subsequent representation of other clients with materially adverse interests in that transaction clearly is prohibited. On the other hand, a lawyer who recently handled a type of problem for a former client is not precluded from later representing another client in a factually distinct problem of that type even though the subsequent representation involves a position adverse to the prior client. Similar considerations can apply to the reassignment of military lawyers between defense and prosecution functions within the same military jurisdictions. The underlying question is whether the lawyer was so involved in the matter that the subsequent representation can be justly regarded as a changing of sides in the matter in question.
 Matters are “substantially related” for purposes of this Rule if they involve the same transaction or legal dispute or if there otherwise is a substantial risk that confidential factual information as would normally have been obtained in the prior representation would materially advance the client’s position in the subsequent matter. For example, a lawyer who has represented a businessperson and learned extensive private financial information about that person may not then represent that person’s spouse in seeking a divorce. Similarly, a lawyer who has previously represented a client in securing environmental permits to build a shopping center would be precluded from representing neighbors seeking to oppose rezoning of the property on the basis of environmental considerations; however, the lawyer would not be precluded, on the grounds of substantial relationship, from defending a tenant of the completed shopping center in resisting eviction for nonpayment of rent. Information that has been disclosed to the public or to other parties adverse to the former client ordinarily will not be disqualifying. Information acquired in a prior representation may have been rendered obsolete by the passage of time, a circumstance that may be relevant in determining whether two representations are substantially related. In the case of an organizational client, general knowledge of the client’s policies and practices ordinarily will not preclude a subsequent representation; on the other hand, knowledge of specific facts gained in a prior representation that are relevant to the matter in question ordinarily will preclude such a representation. A former client is not required to reveal the confidential information learned by the lawyer in order to establish a substantial risk that the lawyer has confidential information to use in the subsequent matter. A conclusion about the possession of such information may be based on the nature of the services the lawyer provided the former client and information that would in ordinary practice be learned by a lawyer providing such services.
Lawyers Moving Between Firms
 When lawyers have been associated within a firm but then end their association, the question of whether a lawyer should undertake representation is more complicated. There are several competing considerations. First, the client previously represented by the former firm must be reasonably assured that the principle of loyalty to the client is not compromised. Second, the rule should not be so broadly cast as to preclude other persons from having reasonable choice of legal counsel. Third, the rule should not unreasonably hamper lawyers from forming new associations and taking on new clients after having left a previous association. In this connection, it should be recognized that today many lawyers practice in firms, that many lawyers to some degree limit their practice to one field or another, and that many move from one association to another several times in their careers. If the concept of imputation were applied with unqualified rigor, the result would be radical curtailment of the opportunity of lawyers to move from one practice setting to another and of the opportunity of clients to change counsel.
 Paragraph (b) operates to disqualify the lawyer only when the lawyer involved has actual knowledge of information protected by Rules 1.6 and 1.9(c). Thus, if a lawyer while with one firm acquired no knowledge or information relating to a particular client of the firm, and that lawyer later joined another firm, neither the lawyer individually nor the second firm is disqualified from representing another client in the same or a related matter even though the interests of the two clients conflict. See Rule 1.10(b) for the restrictions on a firm once a lawyer has terminated association with the firm.
 Application of paragraph (b) depends on a situation’s particular facts, aided by inferences, deductions or working presumptions that reasonably may be made about the way in which lawyers work together. A lawyer may have general access to files of all clients of a law firm and may regularly participate in discussions of their affairs; it should be inferred that such a lawyer in fact is privy to all information about all the firm’s clients. In contrast, another lawyer may have access to the files of only a limited number of clients and participate in discussions of the affairs of no other clients. In the absence of information to the contrary, it should be inferred that such a lawyer in fact is privy to information about the clients actually served but not those of other clients. In such an inquiry, the burden of proof should rest upon the firm whose disqualification is sought.
 Independent of the question of disqualification of a firm, a lawyer changing professional association has a continuing duty to preserve confidentiality of information about a client formerly represented. See Rules 1.6 and 1.9(c).
 Paragraph (c) provides that information acquired by the lawyer in the course of representing a client may not subsequently be used or revealed by the lawyer to the disadvantage of the client. However, the fact that the lawyer has once served a client does not preclude the lawyer from using generally known information about that client when later representing another client.
 The provisions of this Rule are for the protection of former clients and can be waived if the client gives informed consent, which consent must be confirmed in writing under paragraphs (a) and (b). See Rule 1.0(e). With regard to the effectiveness of an advance waiver, see Comment  to Rule 1.7. With regard to disqualification of a firm with which a lawyer is or was formerly associated, see Rule 1.10.
Suing a Former Client on Behalf of a Current Client
Louisiana Rule 1.7 prohibits a lawyer from taking an adverse position to a current client in any matter. Thus, a lawyer defending a client in a minor redhibition matter could not simultaneously sue that client in an unrelated personal-injury matter. This prohibition exists to ensure that a lawyer remains loyal to the lawyer’s current clients.
In contrast, Louisiana Rule 1.9(a) generally permits a lawyer to be adverse to a former client. Thus, a lawyer who has completed the defense of a client in a minor property-related legal matter would be permitted to sue that former client in an unrelated tort action. A lawyer is permitted to sue the lawyer’s former clients because the lawyer’s duty of loyalty abates to some extent after termination of representation. However, Louisiana Rule of Professional Conduct 1.91 does impose a significant limitation on a lawyer’s ability to sue his former clients. A lawyer cannot represent “another person”2 adverse to a former client “in the same or a substantially related matter,”3 unless the former client “gives informed consent, confirmed in writing.” La. Rules of Prof’l Conduct r. 1.9(a).4 Additionally, a lawyer may not intervene on behalf of a current client against a former client “in the same proceeding in which the lawyer initially represented the former client.” See Dhaliwal v. Dhaliwal, 184 So. 3d 773, 782-83 (La. Ct. App. 2d Cir. 2015).
This rule exists both to enforce the lawyer’s residual duty of loyalty to the former client, and to protect the former client’s confidential information from misuse. See La. Rules of Prof’l Conduct r. 1.9(a); In re Cook, 319 o. 3d 272 (La. 2018); In re Abadie Inter Vivos Trust, 791 So. 2d 181, 185 (La. Ct. App. 4th Cir. 2001) (“Rule 1.9 of the Rules of Professional Conduct seeks to protect each client from the use or misuse of that client’s confidential information by a lawyer and to assure the lawyer’s loyalty to each client.”); In re American Airlines, Inc., 972 F.2d 605, 618-19 (5th Cir. 1992); Parker v. Rowan Cos., Inc., No. 03-0545 2003 WL 22852218 (E.D. La. Nov. 25, 2003) (“There are two underlying concerns of the substantial relationship test: ‘the duty to preserve confidences and the duty of loyalty to the former client.’”); see also Restatement (Third) of the Law Governing Lawyers § 132 (2000).
Whether two matters are “substantially related” turns on all of the relevant facts and circumstances. In resolving the issue, courts often consider the similarity of the pertinent legal and factual issues presented, the lapse of time, the overlap of parties, and the overlap of witnesses and documents. See generally Charles Wolfram, Former Client Conflicts, 10 Geo. J. Legal Ethics 677 (1997). The Louisiana Supreme Court has defined the meaning of the term “substantially related” as follows: “In our view, two matters are ‘substantially related’ when they are so interrelated both in fact and substance that a reasonable person would not be able to disassociate the two.” See Walker v. La. Dep’t of Transp. & Development, 817 So. 2d 57, 62 (La. 2002); see also Parker, 2003 WL 22852218, at *10 (E.D. La. 2003) (“[T]he substantial relationship test requires common subject matters, issues and causes of action, but it does not require the same factual scenarios in both cases.”); Koch v. Koch Indus., Inc., 798 F. Supp. 1525, 1536 (D. Kan.1992) (“substantially related” means that the cases “involve the same client and the matters or transactions in question are relatively interconnected”), rev’d on other grounds, Koch v. Koch Indus., Inc., 203 F.3d 1202 (10th Cir. 2000); Trust Corp. v. Piper Aircraft Corp., 701 F.2d 85, 87 (9th Cir. 1983) (“substantially related” means that “the factual contexts of the two representations are similar or related”).
In Parker v. Rowan Cos., Inc., United States District Judge Vance of the Eastern District of Louisiana observed that cases addressing the substantial-relationship issue “fall along a continuum, from those in which the linkage is clear to those in which the connection is nebulous and superficial.” Parker, 2003 WL 22852218, at *5. On one end of the spectrum are cases in which former clients have sought–unsuccessfully–to disqualify a former lawyer on the basis of “superficial” resemblances between past and present matter. On the other end of the spectrum are cases in which former clients have identified “specific issues” common to the former and present matters, and have described in “detail the extent of the attorney’s involvement” in both cases. See id. at *6-*7. In Parker, Judge Vance found more than “superficial similarities,” and disqualified a lawyer from suing his former client because both the present and former matters: involved Jones Act and unseaworthiness claims; alleged damages for pain and suffering, lost future wages, and emotional distress; involved the same corporate representative, the same rig, and the same crew members; presented safety training issues; and, raised issues relating to subsequent remedial measures. See id. at *9-*10. Moreover, the fact that the former client “viewed [the former lawyer] as a part of its team of defense lawyers, regularly communicating and sharing information with it on matters [it] considered important to its defense of maritime personal injury cases, such as case law developments” provided “additional insight” into the context of the former attorney-client relationship, although it was not in and of itself dispositive. See id. at *10.
Although a lawyer’s duty of loyalty diminishes precipitously upon termination of representation, the independent duty to preserve the confidentiality of information relating to the representation does not. See La. Rules of Prof’l Conduct Rule 1.6(a) (2004). A corollary of this continuing confidentiality obligation set forth in Louisiana Rule 1.9(c), is that a lawyer may not use confidential information to the disadvantage of a former client, unless that information has become generally known. Thus, even when a lawyer is permitted to sue a former client in an unrelated matter, the lawyer still cannot use confidential information in the course of that otherwise permissible adverse representation.
Use of Confidential Information of Former Client by a Lawyer
Both the ABA Model Rules of Professional Conduct and the corresponding Louisiana Rules broadly prohibit a lawyer from revealing former-client confidences. A lawyer may do so rarely and then only when a specific exception in the rule governing existing-client confidentiality applies.
The rules, however, permit more liberal use of former-client confidences. ABA Model Rule 1.9(c)(1) and Louisiana Rule 1.9(c)(1) permit a lawyer to use confidential information if it does no harm to a former client. Moreover, the rules permit use of such information to the disadvantage of a former client “when the information has become generally known.” See ABA Comm. on Ethics & Prof’l Responsibility, Formal Op. 479 (Dec. 17, 2017).
But confusion exists as to just when information is “generally known.” Some lawyers believe, incorrectly, that information is “generally known” when it is a matter of public record or when it is publicly accessible. On the contrary, “the fact that the information may have been discussed in open court, or may be available in court records, in public libraries, or in other public repositories does not, standing alone, mean that the information is generally known for Model Rule. 1.9(c)(1).” Indeed, “[I]nformation that is publicly available is not necessarily generally known.” See id. at 5.
Formal Opinion 479 attempts to clear up this confusion and to craft a “workable definition” of the generally-known standard. To this end, the opinion defines two circumstances under which information is “generally known.”
First, information is “generally known” when it is “widely recognized by members of the public in the relevant geographic area.” Id. Such wide recognition- or “public notoriety”- can result from “publicity through traditional media sources, such as new papers, magazines, radio, or television; through publication on internet websites; or through social media.” Id.
Second, information is “generally known” when it is “widely recognized in the former client’s industry, profession, or trade.” Such recognition can exist if the information “is announced, discussed, or identified in what reasonable members of the industry, profession, or trade would consider a leading print or online publications or other resource in the particular field. Information may be widely recognized within a former client’s industry, profession, or trade without being widely recognized by the public.” Id.
General Knowledge of a Former Client’s Policies
Conflict-of-interest charges by former clients are particularly nettlesome when the lawyer has done a substantial amount of work on numerous matters for a former client. A recent ABA ethics opinion addressing the duties of former in-house lawyer notes that a lawyer’s “general knowledge of the strategies, policies, or personnel” of the former client is “not sufficient by itself to establish a substantial relationship between the current matter” and past matters. See ABA Comm. on Ethics and Prof’l Responsibility, Formal Op. 99-415 (1999). Moreover, the mere “appearance of impropriety”5 does not render the former lawyer’s representation improper absent substantial relationship or the use of confidential information. See In re American Airlines, 972 F.2d 605, 619 (5th Cir. 1992) (“[T]he ‘appearance of impropriety’ has no relevance to our probe of ethical restraints.”); Parker, 2003 WL 22852218 (E.D. La. Nov. 25, 2003) (same).
A violation of Rule 1.9 typically disqualifies the lawyer–and his firm6–from representing a party adverse to his former client. Indeed, the Louisiana Supreme Court has held that “[t]he customary remedy for an alleged conflict of interest is disqualification of the attorney or firm with the conflict.” See Walker, 817 So. 2d at 60 (citing Corbello v. Iowa Production Co., 787 So. 2d 596 (La. Ct. App. 3d Cir. 2001)); see generally Restatement (Third) of the Law Governing Lawyers § 6 (2000) (“For a lawyer’s breach of a duty owed to the lawyer’s client, judicial remedies include . . . disqualifying a lawyer from representation.”).
The “burden of proving disqualification of an attorney or other officer of the court rests on the party making the challenge.”7 See State v. Craddock, 62 So. 3d at 797 (La. Ct. App. 1st Cir. 2011) (citing Walker, 817 So. 2d at 60); see also Duncan v. Merrill Lynch, Pierce, Fenner & Smith, Inc., 646 F.2d 1020, 1028 (5th Cir. 1981) (overruled on other grounds by Gibbs v. Paluk, 742 F.2d 181, 186 (5th Cir. 1986); Gibbs court acknowledged that it created a conflict in the rulings of the circuit courts); Sumpter v. Hungerford, No. 12-717, 2013 WL 2181296 (E.D. La. May 20, 2013) (quoting Parker, 2003 WL 22852218, at *5) (“The party who seeks to disqualify his former lawyer bears the burden of proving that the present and former representations are substantially related.”); Franklin v. Regions Bank, No. 5:16-1152, 2018 WL 2449208 (W.D. La. May 31, 2018) (noting that the “standard for disqualification of counsel is high”)). To carry this burden, the movant must “‘delineate with specificity the subject matters, issues and causes of action presented in the former representation’ so that the district court can determine if the substantial relationship test has been met.” Parker, 2003 WL 22852218, at *5 (E.D. La. 2003) (quoting Duncan, 646 F.2d at 1029). The party seeking to disqualify his opponent’s lawyer under Rule 1.9 may be entitled to an in camera hearing in order to protect confidential information. See Keith v. Keith, 140 So. 3d 1202 (La. Ct. App. 2d Cir. 2014).
The policies underlying the “customary remedy” of disqualification are significant: “[d]isqualification, where appropriate, ensures that the case is well presented in court, that confidential information of present or former clients is not misused, and that a client’s substantial interest in a lawyer’s loyalty is protected.” See Restatement (Third) of the Law Governing Lawyers § 6 cmt. i (2000). However, in evaluating whether disqualification is appropriate, courts must not ignore the significant associated costs:
The costs imposed on a client deprived of a lawyer’s services by disqualification can be substantial. At a minimum, the client is forced to incur the cost of finding a new lawyer not burdened by conflict in whom the client has confidence and educating that lawyer about the facts and issues. The costs of delay in the proceeding are borne by that client in part, but also by the tribunal and society. Disqualification is often the most effective sanction for a conflict of interest and will likely continue to be vigorously applied where necessary to protect the integrity of a proceeding or an important interest of the moving party. In applying it, however, tribunals should be vigilant to prevent its use as a tactic by which one party may impose unwarranted delay, costs, and other burdens on another. Id.
When disqualification is appropriate, it must be sought expeditiously. Louisiana courts have repeatedly held that a party seeking to disqualify a lawyer must object to the representation so timely or else waive the right to seek disqualification later. See, e.g., Barre v. St. Martin, 636 So. 2d 1061, 1063-1064 (La. Ct. App. 5th Cir. 1994) (reasoning that failure to object timely tacitly waives a party’s right to seek disqualification); Brasseaux. v. Girouard, 214 So. 2d 401, 409 (La. Ct. App. 3d Cir. 1968) (reasoning that allowing a tardy objection in this context would allow disqualification to be used as a “purely dilatory or obstructive tactic”); Lalande v. Index Geophyscial Survey Corp., 336 So. 2d 1054, 1057 (La. Ct. App. 3d Cir. 1976) (citing Brasseaux and noting that a late-moving party “may expressly or tacitly waive his objection” by delay). For example, one court denied disqualification because the moving party waited eight months to seek disqualification. See Corbello v. Iowa Prod. Co., 787 So. 2d 596 (La. Ct. App. 3d Cir. 2001). The court held that “disqualification could be used as an obstructive tactic and, therefore, the right to urge disqualification of an opposing counsel may be waived by the failure to raise the issue early in the proceedings.” Id. at 599; see also Walker, 817 So. 2d at 63 (denying disqualification and noting that the “State waited seven months in one matter and thirteen months in the other matter before taking action to disqualify Vidrine ….”). See also Kashi v. McGraw-Hill Glob. Educ. Holdings, No. 17-1818, 2018 WL 4094958 (D. Pa. Aug 27, 2018) (denying motion to disqualify for ten-month delay); In re Waterstone Owners Assoc., Inc., No. 03-18-00352-CV, 2018 WL 4016860 (Ct. App. Tx. 3d Dist. Aug. 23, 2018) (denying motion to disqualify for nine-month delay).
For the disciplinary sanctions that are appropriate for a lawyer’s failure to avoid conflicts of interest, see supra Annotations to Louisiana Rule 1.7; In re Cudzik, 738 So. 2d 1054, 1058-59 (La. 1999) (applying standard 4.3 to Rule 1.9 violation); see also In re Barrios, 929 So. 2d 63 (La. 2006) (suspending lawyer for two years for violation of 1.9 among other violations).
This page was updated on January 10, 2020.
- In determining whether former-client conflict requires disqualification, Louisiana courts typically look to the Louisiana Rules of Professional Conduct. See, e.g., State v. Craddock, 62 So. 3d 791, 797 (La. Ct. App. 1st Cir. 2011) (citing Walker v. La. Dep’t of Transp. & Dev., 817 So. 2d 57, 59-60 (La.2002); Farrington v. The Law Firm of Sessions, Fishman, 674 So. 2d 448 (La. Ct. App. 4th Cir. 1996) rev’d judgment by Farrington v. Law Firm of Sessions, Fishman, 687 So. 2d 997 (La. 1997)). This is not surprising given that the Louisiana Supreme Court has consistently and repeatedly held that “the ethical rules which regulate attorneys’ law practices have been recognized as having the force and effect of substantive law.” See Walker, 817 So. 2d at 59-60 (citing Leenerts Farms, Inc. v. Rogers, 421 So. 2d 216 (La.1982); Saucier v. Hayes Dairy Prods., Inc., 373 So. 2d 102 (La.1979); Husk v. Blancand, 99 So. 610 (1924)). ↵
- Rule 1.9 does not disqualify a lawyer from representing himself when he has been sued by a former client. According to the Louisiana Supreme Court, “the rule’s very wording–represent another person–connotes that the lawyer is representing someone other than the lawyer appearing on his or her own behalf.” See Farrington v. Law Firm of Sessions, Fishman, 687 So. 2d 997, 1001 (La. 1997). ↵
- Likewise, federal caselaw is “categorical in requiring disqualification once a substantial relationship between past and current representations is established.” See In re American Airlines, Inc., 972 F.2d 605, 614 (5th Cir. 1992); see also In re Dresser Indus. Inc., 972 F.2d 540, 543 (5th Cir. 1992); Parker v. Rowan Cos, Inc., 2003 WL 22852218 (E.D. La. Nov. 25, 2003) (finding that disqualifying movant need not prove communication of confidential information or its use). ↵
- Although the standards set forth in the substantial-relationship test of Rule 1.9(a) are straightforward, some courts have analyzed former-client conflicts by applying “irrebuttable presumptions.” See, e.g., Parker v. Rowan Cos., Inc., 2003 WL 22852218 (E.D. La. Nov. 25, 2003). The court in Parker, following United States Fifth Circuit precedent, characterized the former-client conflict analysis as follows:
Two irrebuttable presumptions apply under the substantial relationship test in this circuit: First, once it is established that the previous matters are substantially related to the present case, “the court will irrebuttably presume that relevant confidential information was disclosed during the former period of representation.” . . . Second, there is an irrebuttable presumption that “confidences obtained by an individual lawyer will be shared with the other members of his firm.”
Id. at *5 (citations omitted). But see Kennedy v. Mindprint, 587 F.3d 296, 304 n. 7 (5th Cir. 2009) (“It is unclear whether a rebuttable presumption replaces the American Airlines irrebuttable presumption, or whether no presumption remains. We do not reach this question . . .”). While this approach is not necessarily erroneous, it is needlessly complicated because it adds nothing to the substantial-relationship standard set forth in the test of Rule 1.9(a). ↵
- This term is a relic of Canon 9 of the 1969 ABA Model Code of Professional Responsibility. See Model Code of Prof’l Responsibility Canon 9 (1969) (“A lawyer should avoid even the appearance of professional impropriety.”); Warren L. Mengis, Developments in the Law 1986-1987–Professional Responsibility, 48 La. L. Rev. 437, 439 (1987) (“The old Canon 9 ‘appearance of impropriety’ has now been suppressed.”). The ABA later clarified that a lawyer should not be sanctioned or disqualified under such an “undefined,” “question-begging” standard. See ABA Comm. on Ethics & Prof’l Responsibility, Formal Op. 342 (1975). ↵
- See La. Rules of Prof’l Conduct r. 1.10. But see State in Interest of L.R., 314 So. 3d 1139, 1144 (La. Ct. App. 4th Cir. 2021) (noting that the recusal of an entire district attorney’s office is not required when an assistant district attorney previously worked on the case) ↵
- Because the movant bears the burden of proof, “the right of an attorney freely to practice his profession must, in the public interest, give way in cases of doubt.” See Doe v. A Corp., 709 F.2d 1043, 1047 (5th Cir. 1983) (quoting Chugach Elec. Ass’n v. U.S. Dist. Ct., 370 F.2d 441, 444 (9th Cir. 1966)). ↵