OPINION
Bryсe Anderson (Anderson) sued Center-line Industries, Inc. (Centerline) and others in the district court of Ellis County. Robert *875 E. Rader, Jr. and the firm of Rader, Campbell, Fisher & Pyke represent Anderson. Centerline аsked Respondent, the Honorable Gene Knize, Judge of the 40th Judicial District Court, to disqualify Rader and his firm because he had previously represented Cen-terline in a “substantially related matter.” See TexDisciplinaRY RJPROf.Conduct 1.09 (1991), reprinted in Tex. Gov’t Code Ann. tit. 2. subtit. G app. (Vernon Supp.1995) (State BaR Rules art. X, § 9). Respondent denied Centerline’s motion.
Centerline asserts in a petition for a writ of mandamus that Respondent abused his discretion in denying the motion becаuse Rule 1.09 clearly and specifically disqualifies Rader and his firm and because both the Texas Supreme Court and the Fifth Circuit have interpreted the rule so as to disqualify him.
See id.; NCNB Texas Nat’l Bank v. Coker,
A writ of mandamus may be issued to corrеct a “clear abuse of discretion.”
Walker v. Packer,
Rule 1.09 of the Texas Disciplinary Rules of Professional Conduct, entitled “Conflict of Interest: Former Client,” provides in pertinent part:
(a) Without prior consent, a lawyer who personally has formerly represented a client in a matter shall not thereafter represent another person in a matter adverse to the former client:
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(2) if the representation in reasonable probability will involve a violation of Rule 1.05; or
(3) if it is the same or a substantially related matter.
TexDisciplinaRY R.PROf.Conduct 1.09. Subsection (b) of the rule extends an individual lawyer’s conflict to mеmbers of the lawyer’s firm under most circumstances. Id.
Anderson makes no claim that the matter now before the District Court is not “substantially related” to the former matter in which Rader represented Centerline.
See id.
Indeed, he concedes that it is. He does not assert that Rader had no attorney-client relationship with Centerline. He does not suggest that the disqualification, if granted, should not extend to Rader’s firm. Instead, he contends that the court was correct in refusing to disqualify Rader because: (1) the comment to the rule shows that it was intended to apply only when there is a threat that confidential communications might be disclosed and, because all confidences that Radar obtained from Centerline have been publicly disclosed in another proceeding, the rule does not apply in this case; аnd (2) the Supreme Court has interpreted the rule in a manner consistent with that view of the comment.
See id.; Metropolitan Life Ins. Co. v. Syntek Finаnce Corp.,
The comment published with the rule, after discussing subparagraph (a)(2) and the “same” provision of subparagraph (a)(3), stаtes in part:
The “substantially related” aspect, on the other hand, has a different focus. Although that term is not defined in the Rule, it primarily involves situations where a lawyer could have acquired confidential information concerning a prior client that could be used еither to that prior client’s disadvantage or for the advantage of the lawyer’s current client or some other person. It thus largеly overlaps the prohibition contained in paragraph (a)(2) of this Rule.
TexDisciplinaRY R.PROf.Conduct 1.09 cmt. 4A. 1 However, subsection (a)(3) of the rule *876 is stated m plain language and its meaning is clear. Id. 1.09(a)(3). We believe that it establishes a simple prohibition: Without a former client’s consent, a lawyer should not represent another person in a matter adverse to the former client whеn the lawyer represented the former client in the same matter or a substantially related matter. Id.
In
Coker,
the Supreme Court held that, onсe the matters are shown to be substantially related, the former client “is entitled to a conclusive presumption that confidences and secrets were imparted to the former attorney.”
Coker,
In
American Airlines,
the Fifth Circuit reaffirmed that a federal district court “is
obliged
to take measures against unethical conduct occurring in connection with any proceeding bеfore it.”
American Airlines,
Anderson’s reliance on
Syntek
is misplaced.
See Syntek Finance,
Anderson’s admission that Rader formerly represented Centerline in a matter that is substantially related to the prеsent matter ends the inquiry. Respondent had no discretion to deny Centerline’s motion to disqualify Rader and his firm. We conditionally grant a writ of mandаmus; because we are confident that Respondent will comply with our decision, the writ will issue only if he fails to do so.
Notes
. The applicable part of the comment was renumbered as paragraph 4B by the State Bar Board of Directors on September 16, 1994, as noted in 890 S.W.2d C, Cl.
