dissenting.
I believe that Article III, Section 19 bars a holder of a lucrative office from running *781for the legislature during the entire “term” for which he or she is appointed or elected, not merely for that portion of the term actually served. I therefore respectfully dissent.
I
A
The constitutional provision at issue states as follows:
No judge of any court, Secretary of State, Attorney General, clerk of any court of record, or any person holding a lucrative office under the United States, or this State, or any foreign government shall during the term for which he is elected or appointed, be eligible to the Legislature.
Tex. Const, art. Ill, § 19. Of particular importance hiere is the language “during the term for which he is elected or appointed....” The Court concludes that the “term” for which an officeholder is appointed ends when he or she resigns. I believe that this language refers to the entire term of the appointment, whether or not the officeholder serves the full term.
Wentworth was appointed to a six-year term on the Board of Regents of the Texas State University System. Wentworth’s resignation did not bring an end to this term. When a public officer resigns, dies or is otherwise unable to serve, a successor is elected or appointed to fill the unexpired portion of the term. For example, our Constitution elsewhere provides:
In case of a vacancy in the office of the Chief Justice or any Justice of the Supreme Court, the Governor shall fill the vacancy until the next general election for state officers, and at such general election the vacancy for the unexpired term, shall be filled by election by the qualified voters of the state....
Tex. Const, art. V, § 2 (emphasis added). Similarly, the Texas Election Code sets forth procedures for filling the “unexpired term” of a vacant state office. See Tex. Elec.Code §§ 202.002-202.007. A “term,” therefore, refers to the length of time the officeholder is elected or appointed to serve, not to the actual length of service.
As Justices Gonzalez, Hecht and Cornyn point out in their concurring opinions, there is some ambiguity on the face of Section 19 because it applies in the first instance to persons “holding” lucrative office. If the officer has resigned, he or she is no longer “holding” office and arguably does not fall under the restriction. Justice Hecht goes on to suggest that, under this interpretation, the phrase “during the term for which he is elected or appointed” is not surplus-age because it can interpreted as a limitation on the restriction; i.e., clarification that the restriction does not apply to officers who are holding over in office beyond their terms, awaiting qualification of their successors.
If we were construing Section 19 in a vacuum, I might be inclined to resolve this ambiguity in favor of eligibility. However, this Court has twice interpreted this provision as precluding a lucrative officeholder from serving in the legislature for the entire term of the office, even if he or she resigns before its expiration. Lee v. Daniels, 377 S.W.2d 618 (Tex.1964); Kirk v. Gordon, 376 S.W.2d 560 (Tex.1964). The history of Section 19, as well as Section 18 preceding it, persuade me that these decisions were correct and should not be overruled.
As originally drafted by the Legislative Committee of the 1875 Constitutional Convention, Section 19 provided as follows:
No judge of any court, Secretary of State, Attorney General, clerk of any court of record, or any person holding a lucrative office under the United States or this State, or any foreign government, shall be eligible to the Legislature.
Journal of the Constitutional Convention of the State of Texas, 1875 156 (1875) [hereinafter Journal ]. This draft in relevant respects matched the restriction contained in earlier Constitutions.1 Thus, the *782Committee draft, like the earlier Constitutions, disqualified the designated officeholders from legislative candidacy only while holding office, not for their entire term. On the floor of the Convention, however, delegate J.B. Murphy of Nueces County moved to amend the section by inserting after the word “shall” the phrase “during the term for which he is elected or appointed.” Journal at 210. This change was adopted. Id.
The wording of Murphy’s amendment was almost identical to language in the Legislative Committee’s draft of the preceding provision of the Constitution, Section 18, which provided:
No senator or representative shall, during the term for which he may be elected, be eligible to any civil office of profit under this State, which shall have been created, or the emoluments of which may have been increased during such term; no member of either house shall, during the term for which he is elected, be eligible to any office or place, the appointment to which may be made, in whole or in part, by either branch of the Legislature....
Journal at 156 (emphasis added). This language was adopted without change and remains in effect today. Tex. Const, art. Ill, § 18. Thus, the temporal restriction of Section 18 (“during the term for which he may be elected”) was added to Section 19 in almost identical form.
Clearly, in Section 18 the meaning of the phrase “during the term for which he may be elected” is unambiguous. The purpose of that section is to prevent a legislator from voting to create an office or make an office more lucrative, then resigning his or her legislative seat to accept that office. See 1 George D. Braden, et al., The Constitution of the State of Texas: An Annotated and Comparative Analysis 132-34 (1977). To accomplish that purpose, the “during the term” language must encompass the legislator’s entire term, not just the portion served. See generally Tex. Const, art. Ill, § 18, interp. commentary (Vernon 1984) (“The language is designed to prevent legislators from resigning to take state offices which have been created, or the emoluments of which may have been increased during their term of office.”).
By using virtually identical words in Sections 18 and 19, I believe that the framers intended the same result. Cf. Boriack v. Boriack, 541 S.W.2d 237, 240 (Tex.Civ.App.—Corpus Christi 1976, writ dism’d) (a word or phrase used in different parts of a statute should be interpreted the same throughout); Greenwood v. City of El Paso, 186 S.W.2d 1015, 1017 (Tex.Civ.App.—El Paso 1945, no writ) (same).2
Texas is apparently the only state that bars officeholders from the legislature “during the term” of the office. Other states extend the restriction only to persons currently “holding” office, as did Texas prior to 1876.3 However, many other states impose restrictions similar to Article III, Section 18, limiting a legislator’s ability to hold other office during the term for which the legislator was elected.4 Many of *783these provisions contain language virtually identical to the language at issue in the present case. Most courts have construed this language as referring to the legislator’s entire term, regardless whether he or she resigns. See, e.g., Chenoweth v. Chambers, 33 Cal.App. 104, 164 P. 428 (1917); In re Advisory Opinion to the Governor, 94 Fla. 620, 113 So. 913 (1927); Rowe v. Tuck, 149 Ga. 88, 99 S.E. 303 (1919); In re Opinions of the Justices, 95 Me. 564, 51 A. 224 (1901); Wachter v. McEvoy, 125 Md. 399, 93 A. 987 (1915); Richardson v. Hare, 381 Mich. 304, 160 N.W.2d 883 (1968); State ex rel. Childs v. Sutton, 63 Minn. 147, 65 N.W. 262 (1895). But see Rugg v. Town Clerk of Arlington, 364 Mass. 264, 303 N.E.2d 723 (1973). These decisions are consistent with our holdings in Lee and Kirk, and I would follow the same rule here.
B
Wentworth’s Board of Regents term overlaps his potential Senate term by only 19 days. Wentworth argues that this overlap is de minimis and should be ignored.
Tex. Const, art. Ill, § 18 was amended in 1968 to allow for a de minimis term overlap when legislators move to some other civil office. Wentworth argues that by amending Section 18, the State has recognized that a de minimis overlapping of terms is not against the public interest. However, the people adopted a de minimis exception only for Section 18, not Section 19. Even if we accept Wentworth’s argument that the policy rationale underlying the change in Section 18 would apply with equal force to Section 19, we cannot judicially amend the plain language of the Constitution based on policy reasons.
II
Wentworth next argues that if my interpretation of Section 19 is correct, its application in this case violates his right to equal protection of the laws under the Fourteenth Amendment of the United States Constitution. I disagree.
The United States Supreme Court has previously upheld Article III, Section 19 against an equal protection attack. Clements v. Fashing, 457 U.S. 957, 102 S.Ct. 2836, 73 L.Ed.2d 508 (1982). Clements involved a justice of the peace who desired to run for the legislature before the expiration of his judicial term. A four-justice plurality5 held that Section 19 created only “insignificant interference with access to the ballot,” 457 U.S. at 968, 102 S.Ct. 2836, 73 L.Ed.2d 508, and therefore “need only rest on a rational predicate in order to survive a challenge under the Equal Protection Clause.” Id. The plurality found that rational predicate, noting that the restriction 1) prevented officeholders from abusing or neglecting their office while campaigning for the legislature, and 2) encouraged officeholders to serve their full terms, thereby reducing the problems caused by interim elections and appointments. Id.
Justice Hecht notes that “[ojnly a plurality” of the Supreme Court found a rational purpose for my construction of Section 19. 839 S.W.2d at 775. This, however, does not weaken the effect of Clements. The fifth justice joining in the judgment, Justice Stevens, concluded that the equal protection clause was not even implicated because “there is [no] federal interest in requiring a State to define the benefits and burdens of different elective state offices in any particular manner.” 457 U.S. at 974,102 S.Ct. at 2849 (Stevens, J., concurring). He thus would have upheld the provision without any showing of a rational basis for the classification. Id. at 974-75, 102 S.Ct. at 2849.
The plurality recognized that preventing abuse of office was “especially important *784with regard to judicial officers,” id., pointing out that “[t]he State’s particular interest in maintaining the integrity of the judicial system could support § 19, even if such a restriction could not survive constitutional scrutiny with regard to any other officeholder.” Id. at 968 n. 5, 102 S.Ct. at 2846 n. 5. Based on these comments, Went-worth seeks to limit the holding of Clements to judicial officers, thereby distinguishing the present case.
I do not read Clements so narrowly. The State has a legitimate interest in preventing abuse and neglect by all its officers, not just judges. Further, the second rationale provided by the plurality, encouraging officeholders to serve out their terms, applies with at least equal force to university regents as it does to justices of the peace. I would therefore hold that Section 19 does not violate Wentworth’s equal protection rights.
Ill
A
Since resigning his Board of Regents position, Wentworth has been elected three times to the Texas House of Representatives. Wentworth therefore argues that this present challenge to his eligibility for the legislature is barred by a legislative version of res judicata.
Tex. Const, art. Ill, § 8 provides:
Each House shall be the judge of the qualifications and election of its own members; but contested elections shall be determined in such manner as shall be provided by law.
Wentworth contends that the House of Representatives’ decision to seat him for two terms was “judicial” in nature and precludes this present attack on his eligibility for the legislature.
First, it must be noted that Section 8 does not deprive this Court of jurisdiction to determine a candidate’s qualifications. Kirk v. Gordon, supra. Second, even if the House’s decision to seat Wentworth can be called “judicial,” I do not believe that Wentworth’s estoppel argument is properly characterized as a res judicata challenge.
Res judicata precludes a party from relit-igating the same cause of action. Gracia v. R.C. Colar-7-Up Bottling Co., 667 S.W.2d 517, 519 (Tex.1984). The “cause of action” in this mandamus proceeding concerns Wentworth’s eligibility to be the Republican candidate for District 26 of the Texas Senate on the 1992 general election ballot. No tribunal, judicial or legislative, has previously addressed this dispute, except the court of appeals below. Went-worth’s estoppel argument, rather than going to his entire cause of action, concerns a specific legal issue: the interpretation of Article III, Section 19. Wentworth’s argument, if anything, is in the nature of a collateral estoppel challenge.
Collateral estoppel requires, among other things, actual litigation of the issue. See Puga v. Donna Fruit Co., 634 S.W.2d 677, 680 (Tex.1982). There is no indication in the record that the issue of Wentworth’s alleged ineligibility under Section 19 was ever actually considered by the House of Representatives. Further, collateral estop-pel only precludes persons who were parties to the prior action, or those in privity with them. See Benson v. Wanda Petroleum Co., 468 S.W.2d 361, 363 (Tex.1971). Neither the Senate nor Respondent Meyer were parties to the House’s decision to seat Wentworth, and thus they cannot be es-topped by that decision.
B
Justice Mauzy would hold that Meyer is estopped from declaring Wentworth ineligible because the Chairman of the Republican Party has on several previous occasions — under the same circumstances — certified Wentworth as eligible for the legislature. Justice Mauzy’s approach differs from Wentworth’s estoppel argument in that Wentworth focuses on the action of the House of Representatives in seating him, while Justice Mauzy focuses on the action of the Republican Party Chairman in certifying Wentworth.
Justice Mauzy does not contend that Wentworth somehow detrimentally relied on the Republican Party Chairman’s failure to earlier raise Article III, Section 19. It *785seems, therefore, that Justice Mauzy’s theory more closely resembles “waiver” than “estoppel.” See Tex-Craft Builders v. Allied Construction of Houston, Inc., 465 S.W.2d 786, 793 (Tex.Civ.App.—Tyler 1971, writ ref'd n.r.e.) (waiver depends solely on the conduct of the party holding the right, while estoppel depends on what that party has caused the adversary to do). “Waiver is an intentional relinquishment of a known right or intentional conduct inconsistent with claiming that right.” Sun Exploration and Production Co. v. Benton, 728 S.W.2d 35, 37 (Tex.1987). There is no indication in the record that the Republican Party Chairman, with knowledge of the relevant facts, consciously decided not to raise the Section 19 issue in earlier elections. I do not believe, therefore, that an intentional waiver can be inferred. Furthermore, it would manifestly be against public policy to allow a candidate to circumvent a constitutional eligibility requirement by applying the doctrine of waiver against an election official.
IV _
We recently reaffirmed that an office is “lucrative” within the meaning of Article III, Section 19 if the recipient receives any compensation, no matter how meager. Dawkins v. Meyer, supra. Justice Gam-mage argues that we should revisit this issue and hold that Wentworth’s Board of Regents position was not lucrative and therefore does not bar his run for the legislature. Wentworth, however, does not raise this issue, and I would not revisit the matter on our own motion.
V
For the reasons stated in the plurality opinion and the concurring opinions of Justice Hecht and Justice Cornyn, the Court’s decision today, although in my opinion incorrect, is not inconsistent with our recent holding in Dawkins v. Meyer.
CONCLUSION
For the reasons discussed above, I would hold that Wentworth is ineligible for election to the Texas Senate since the term which he seeks would overlap with his appointive term to the Board of Regents of the Texas State University System.
. Tex. Const, art. Ill, § 30 (1869); Tex. Const, art. Ill, § 24 (1866); Tex. Const, art. Ill, § 25 (1861); Tex. Const, art. Ill, § 25 (1845).
. The fact that Section 19 applies to persons “holding" office does not distinguish it from Section 18. The ambiguity which the word “holding” arguably creates in Section 19 also exists in Section 18, which applies in the first instance to “senators” and “representatives". It could be argued that a legislator is no longer a senator or representative after resigning office.
. See Ariz. Const, art. IV, Pt. 1, § 1(2), Pt. 2, § 4; Ark. Const, art. V, § 7; Colo. Const, art. V, § 8; Conn. Const, art. Ill, § 11; Del. Const, art. II, § 14; Fla. Const, art. II, § 5; Ga. Const, art. Ill, § 2, para. IV(b); Iowa Const, art. Ill, § 22; Me. Const, art. IV, Pt. 3, § 11; Md. Const, art. Ill, § 10, 11; Mass. Const, amend, art. VIII; Mich. Const, art. IV, § 8; Mo. Const, art. Ill, § 12; Mont. Const, art. V, § 9; Neb. Const, art. Ill, § 9; Nev. Const, art. IV, § 9; N J. Const, art. IV, § V, para. 4; Okla. Const, art. V, § 18; Pa. Const, art. II, § 6; R.I. Const, art. Ill, § 6; S.C. Const, art. Ill, § 24; S.D. Const, art. Ill, § 3; Tenn. Const, art. II, § 26; Utah Const, art. VI, § 6; Vt. Const, ch. II, § 54; Va. Const, art. IV, § 4; Wash. Const, art. II, § 14; W.Va. Const, art. VI, § 13; Wis. Const, art. IV, § 13; Wyo. Const, art. Ill, § 8.
.See Ala Const, art. IV, § 59; Alaska Const, art. II, § 5; Ariz. Const, art. TV, Pt. 1, § 1(2), Pt. 2 § 5; Ark. Const, art. V, § 10; Cal. Const, art. IV, § 13; Conn. Const, art. Ill, § 11; Del. Const, art. II, § 14; Haw. Const, art. Ill, § 8; Ill. Const, art. IV, § 2(e); Ind. Const, art. IV, § 30; Iowa Const, art. Ill, § 21; Ky. Const. § 44; Me. Const, art. IV, Pt. 3, § 10; Miss. Const, art. IV, *783§ 45; Mo. Const, art. Ill, § 12; Mont. Const, art. V, § 9; Nev. Const, art. IV, § 8; N.J. Const, art. IV, § V, para. 1; N.M. Const, art. IV, § 28; N.Y. Const, art. Ill, § 7; N.D. Const, art. IV, § 6; Ohio Const, art. II, § 4; Okla. Const, art. V, § 23; Pa. Const, art. II, § 6; S.D. Const, art. Ill, § 12; Utah Const, art. VI, § 7; W.Va. Const, art. VI, § 15; Wis. Const, art. IV, § 12; Wyo. Const, art. Ill, § 8.
. Justice Rehnquist delivered the plurality opinion, joined by Chief Justice Burger and Justices Powell and O’Connor.