OPINION
BALES, Justice.
¶ 1 This special action challenges the qualifications of three nominees to the Arizona Independent Redistricting Commission. On January 19, 2011, we issued an order accepting jurisdiction and granting relief in part, stating that a written opinion would follow. This is that opinion.
I.
¶ 2 In 2000, the voters approved Proposition 106, which amended the Arizona Constitution to require that a five-member Independent Redistricting Commission (“IRC”) draw boundaries for congressional and state legislative districts after every decennial census. The IRC must be constituted by February 28 of each year ending in one. Ariz. Const. art. 4, pt. 2, § 1(3). No more than two Commission members may belong to the same political party. Id. In addition, during the thi’ee years preceding appointment,
members shall not have been appointed to, elected to, or a candidate for any other public office, including precinct committeeman or committeewoman but not including school board member or officer, and shall not have served as an officer of a political party, or served as a registered paid lobbyist or as an officer of a candidate’s campaign committee.
Id.
¶ 3 The Arizona Constitution directs that by January 8 of years ending in one, the Commission on Appellate Court Appointments (“Appointment Commission”) shall nominate twenty-five persons to serve on the IRC, “with ten nominees from each of the two largest political parties in Arizona ... and five who are not registered with either of [131]*131the two largest political parties in Arizona.” Id. §§ 1(4), (5).
¶ 4 After the Appointment Commission has created its list of twenty-five nominees, the highest ranking officer of the Arizona House of Representatives appoints one person from the list to serve on the IRC. Id. § 1(6). Appointments of the next three commissioners are then made from the list successively by the House minority leader, the highest ranking officer of the Arizona Senate, and the Senate minority leader. Id. The four commissioners chosen by the legislative leaders select the fifth, who cannot be a member of any party already represented on the IRC. Id. § 1(8).
¶ 5 In September 2010, the Appointment Commission announced that it was accepting applications from persons interested in serving on the IRC. Seventy-nine people applied, including Mark Sehnepf, Stephen Sossaman, and Paul Bender. Sehnepf and Sossaman, both Republicans, reported on their applications that they serve as directors for irrigation districts. Sehnepf is on the board for the New Magma Irrigation District; Sossaman is on the board for the Queen Creek Irrigation District. Bender, an independent, stated on his application that he serves as “Chief Judge of two Arizona tribal courts.” Bender, a law professor at Arizona State University, serves as the Chief Justice of the Supreme Court of the Port McDowell Yavapai Nation and the Chief Judge of the Court of Appeals of the San Carlos Apache Tribe.
¶ 6 The Appointment Commission met on December 8, 2010, to take public comment, obtain legal advice on eligibility questions, interview forty applicants, and select nominees. The committee selected twenty-five nominees, including Bender, Sehnepf, and Sossaman. Two days later, Kirk Adams, Speaker of the House of Representatives, and Russell Pearce, President of the Senate, asked the Appointment Commission to reconsider, arguing that the three contested nominees were ineligible because they held public office. The two legislators notified Bender, Sehnepf, and Sossaman that they would not consider appointing them and urged them to withdraw. Bender declined; Sehnepf and Sossaman sent withdrawal letters to the Appointment Commission.
¶ 7 On December 29, 2010, the Appointment Commission declined to change its selections and transmitted its list of twenty-five nominees to Adams. The next day, Adams and Pearce filed a petition for special action with this Court, arguing that the three challenged nominees are ineligible because they hold other public office and that Sehnepf and Sossaman are also ineligible because they have withdrawn their applications.
II.
¶ 8 “Our decision to accept jurisdiction of a special action is highly discretionary.” League of Ariz. Cities & Towns v. Martin, 219 Ariz. 556, 558 ¶ 4, 201 P.3d 517, 519 (2009). In invoking this Court’s jurisdiction, Petitioners allege that the Appointment Commission has “failed to ... perform a duty required by law as to which [it had] no discretion,” Ariz. R.P. Spec. Act. 3(a), because it has not established a pool of twenty-five “persons who are willing to serve on and are qualified for appointment” to the IRC. See Ariz. Const. art. 4, pt. 2, § 1(5).
¶ 9 We agree that Petitioners, as the persons entitled to make the first and third appointments to the IRC, have standing to challenge the legality of the Appointment Commission’s list of nominees. See Brewer v. Burns, 222 Ariz. 234, 237-38 ¶¶ 11-14, 213 P.3d 671, 674-75 (2009). We exercise our discretion to accept jurisdiction because “this case involves a dispute at the highest levels of state government” requiring “a pi’ompt determination.” Rios v. Symington, 172 Ariz. 3, 5, 833 P.2d 20, 22 (1992).
III.
A.
¶ 10 Arizona’s constitution states that “[w]ithin the three years previous to appointment,” members of the IRC “shall not have been appointed to, elected to, or a candidate for any other public office, including precinct committeeman or committeewoman but not including school board member or officer.” Ariz. Const, art. 4, pt. 2, § 1(3). Commis[132]*132sioners are also subject to a disqualification provision: “A commissioner, during the commissioner’s terms of office and for three years thereafter, shall be ineligible for Arizona public office or for registration as a paid lobbyist.” Id. § 1(13).
¶ 11 The term “public office” as used in § 1(3) is not defined in the constitution. The sentence in which the term appears, however, provides guidance as to its meaning. Section 1(3) refers to “other public office” in contrast to service as an IRC commissioner, a state office, and “public office” therefore includes other state offices. In addition, § 1(3) excludes school board members. Because school districts are political subdivisions of the state, AR.S. § 15-101(21) (2011), this exclusion implies that public offices of other political subdivisions (e.g., counties or municipalities) are encompassed by the term “public office” in § 1(3). Cf. State Consol. Publ’g Co. v. Hill, 39 Ariz. 21, 28-32, 3 P.2d 525, 528-29 (1931) (holding that municipal officers are subject to prohibition in Article 4, Part 2, Section 17 on changes in compensation of “public officers” during term of office), modified on other grounds, 39 Ariz. 163, 4 P.2d 668 (1931).
¶ 12 Thus, “public office” as used in § 1(3) includes offices of the state or any of its political subdivisions, excluding school board members or officers. Cf. AR.S. § 38-101(1) (defining “office” to mean “any office ... of the state, or any political subdivision thereof, the salary or compensation ... of which is paid from a fund raised by taxation or by public revenue”).
B.
¶ 13 If an irrigation district director holds an “office” of a political subdivision of the state, Schnepf and Sossaman are ineligible to serve as commissioners.
¶ 14 Irrigation districts “derive their powers from the constitution and statutes of Arizona.” Hohokam Irr. & Drainage Dist. v. Ariz. Pub. Serv. Co., 204 Ariz. 394, 397 ¶ 6, 64 P.3d 836, 839 (2003). Article 13, section 7 of the Arizona Constitution states that irrigation districts are “political subdivisions of the state, and vested with all the rights, privileges and benefits, and entitled to the immunities and exemptions granted municipalities and political subdivisions under this constitution.” See also A.R.S. § 48-2901 (“All irrigation districts organized under the laws of this state are declared to be municipal corporations for all purposes.”).
¶ 15 Irrigation districts are managed by elected boards of directors, who, along with a secretary appointed by the board, comprise the “officers” of the district. AR.S. §§ 48-2971. Although irrigation districts have business and economic purposes, rather than a solely governmental one, Local 266, Int’l. Bhd. of Elec. Workers v. Salt River Project Agrie. Improvement & Power Dist., 78 Ariz. 30, 42-43, 275 P.2d 393, 401-02 (1954), then-activities are authorized by the constitution and by statute, and their business is of a public nature similar in some respects to certain statutorily authorized activities of cities and towns. See Ariz. Const, art. 2, § 34 (empowering municipal corporations “to engage in industrial pursuits”); AR.S. § 9-511 (empowering cities and towns to engage in business of a public nature, such as operating a public utility). An irrigation district board of directors has broad powers to acquire and sell water and property, appropriate water and money, levy fines, and construct water and electrical delivery systems. AR.S. § 48-2978.
¶ 16 Because irrigation districts are political subdivisions of the state and their “officers” include their directors, we conclude that Schnepf and Sossaman hold “public office” for purposes of § 1(3), just as officers of a city or a county hold public office. Notably, directors of irrigation districts take the same oath of office as county officials, see AR.S. § 48-2973, -3023, and they are treated like county officers for purposes of recall. See id. § 48-3024 (permitting the recall of directors of irrigation districts and stipulating that the proceedings for such a recall follow what is “provided by the constitution and laws of the state for the recall of county officers”).
¶ 17 Schnepf and Sossaman are therefore ineligible to serve as IRC commissioners. We thus do not address Petitioners’ argu[133]*133ment that they are also ineligible because they are not willing to serve.
C.
¶ 18 Bender is not an officer of the state or any of its political subdivisions. We assume, but need not decide, that he is an “officer” of the two tribes for which he serves as a part-time judge. Bender’s eligibility turns on whether a tribal office is a “public office” under § 1(3) of the constitution.
¶ 19 Petitioners and the amici congressional representatives argue that “public office” must include more than offices of the state or its subdivisions, because the addition of the word “Arizona” before “public office” in the disqualification provision of § 1(13) would otherwise be superfluous. They also note that allowing members of Congress to serve as commissioners would conflict with Proposition 106’s intent to remove self-interested officials from the process of drawing boundaries for their own electoral districts.
¶ 20 The meaning of “public office” cannot be identified without considering the context in which the term appears and the fact that, long before the adoption of § 1(3), the constitution had used the terms “public office” or “public officer” in several other provisions. See Kilpatrick v. Superior Court (Miller), 105 Ariz. 413, 419, 466 P.2d 18, 24 (1970) (recognizing that “constitutions must be construed as a whole and their various parts must be read together”); State ex rel. Jones v. Lockhart, 76 Ariz. 390, 398, 265 P.2d 447, 452-53 (1953) (noting that “no constitutional provision is to be construed piece-meal, and regard must be had to the whole of the provision and its relation to other parts of the Constitution”). There is also force to the argument that “public office” as used in § l(3)’s eligibility provision extends more broadly than the term “Arizona public office” as used in § l(13)’s disqualification provision. We accordingly consider how the term “public office” has been interpreted in Arizona law before the adoption of Proposition 106.
¶ 21 The Enabling Act that resulted in Arizona’s statehood provided for an initial election at which “officers for a full state government, including a governor, members of the legislature, one Representative in Congress, and such other officers as such constitutional convention shall prescribe, shall be chosen by the people.” Act of June 20,1910, ch. 310, § 23, 36 Stat. 557, 571. Consistent with this mandate, delegates at our state constitutional convention approved an ordinance providing that at the initial state election:
[Ojfficers for a full State government shall be chosen by the people, including all the elective State, County, and Precinct officers and members of the Legislature, provided for by said Constitution, and one Representative of Congress. For the purpose of advising the Legislature, the people shall also express at said election, their choice for two United States Senators to represent the State in Congress.
Elec. Ord. No. 2, § 2.
¶ 22 Thus, on the eve of statehood, representatives to Congress were identified as among the “officers for a full state government.” (United States Senators were not directly elected until after the 1913 ratification of the Seventeenth Amendment.) Members of Congress are properly regarded as “officers for ... a state,” even though they are not state officers, inasmuch as they are chosen “by the People” of their respective states, and the vote of representatives may, in rare instances, be taken by state. U.S. Const, art. 1, § 2, els. 1-2; amend. XII (providing that vote of House of Representatives in selecting President shall be taken by state); amend. XVII (providing for direct election of senators).
¶ 23 The Arizona Constitution as drafted in 1910 and implemented in 1912 also contained several references to “public office.” Some of those references have long been understood to include Arizona’s members of Congress. For example, the constitution provides that “[w]hen any office shall, from any cause, become vacant, and no mode shall be provided by the Constitution or by law for filling such vacancy, the governor shall have the power to fill such vacancy by appointment.” Ariz. Const, art. 5, § 8. The inaugural state legislature provided for the filling of certain vacancies, including those in Congress. See Rev. Stat. Ariz. Civ. § 2869 [134]*134(1913) (providing that “[s]pecial elections to fill vacancies in the offices of members of the legislature, representatives in congress or United States senators shall only be held on the proclamation of the governor”); id. § 2870 (providing for interim appointment and election to fill unexpired Senate term upon vacancy).
¶ 24 Arizona’s constitution also broadly declares in Article 8, Part 1, Section 1 that “[e]very public officer in the State of Arizona, holding an elective office ... is subject to recall.” Since statehood, Arizona has had statutory recall provisions directed at members of Congress. Rev. Stat. Ariz. Civ. § 22-3054 to -3364 (1913) (providing for advisory recall elections of members of Congress); A.R.S. §§ 19-221 to -222 (allowing members of Congress to file statements indicating their willingness to resign in response to a recall election).
¶ 25 Also relevant is Article 6, Section 28, of the Arizona Constitution, which provides that “[jjustices and judges of courts of record shall not be eligible for any other public office or for any other public employment during their term of office.” Before 1960, Article 6 stated that supreme court justices and superior court judges “shall not be eligible to any office or public employment” other than judicial office “during the term for which they shall have been elected.” Ariz. Const, art. 6, § 11 (repealed 1960).
¶ 26 In Stockton v. McFarland, a primary candidate argued that this provision rendered his opponent, a superior court judge, ineligible for the United States Senate. 56 Ariz. 138, 139-40, 106 P.2d 328, 328 (1940). The opponent, Ernest McFarland, responded by arguing that the reference to “any office” concerned solely state offices and, in any event, the state could not add to qualifications established by the federal Constitution for Senators. Evidently assuming that “any office” as used in article 6 would include United States Senators (the Court did not address the contrary argument), the Court accepted McFarland’s alternative argument, holding that the federal Constitution bars states from altering the qualifications for members of Congress. Id. at 147-48, 106 P.2d at 331.
¶ 27 Arizona’s legislature has also repeatedly enacted statutes suggesting, at least implicitly, that members of Congress are regarded as holding public office. For example, the state requires the filing of financial disclosures by “public officers.” AR.S. § 38-541(8). Members of Congress are specifically excluded, suggesting that they might otherwise be regarded as “public officers.” Id. Similarly, although Arizona law broadly requires campaign finance disclosures for candidates for public office, candidates for federal office are specifically excluded. A.R.S. § 16-901(2) (excluding candidates for federal office from state campaign disclosure law).
¶ 28 Arizona law, we acknowledge, is not entirely consistent in its use of the terms “office,” “public office,” and “public officer.” Sometimes the constitution expressly distinguishes between federal and state offices. See, e.g., Ariz. Const, art. 4, pt. 2, § 4 (providing that, with certain exceptions, “[n]o person holding any public office of profit or trust under the authority of the United States, or of this state, shall be a member of the legislature”); id. § 5 (providing, with certain exceptions, that legislators during their term “shall [not] be eligible to hold any other office or be otherwise employed by the state of Arizona or, any county or incorporated city or town thereof’); id. art. 22, § 18 (providing that, “[e]xcept during the final year of the term being served, no incumbent of a salaried elective office ... may offer himself for nomination or election to any salaried local, State or federal office”).
¶ 29 The legislature has also sometimes interpreted the constitution’s use of the term “public office” as referring only to offices of the state and its political subdivisions. When the constitution was ratified, Article 7, Section 16 directed the legislature, during its first session, to adopt a law providing for the disclosure of “all campaign contributions to, and expenditures of ... candidates for public office.” The 1912 statute adopted in response required financial disclosures from “candidate[s] for election ... to any state, county, city, or town office.” Rev. Stat. Ariz. Civ. § 3054 (1913). The statute did not men[135]*135tion any disclosures from candidates for federal office.
¶ 30 Arizona law, however, has sometimes treated members of Congress as holding “public office.” Given this backdrop, we agree with Petitioners and the amici representatives that Arizona’s members of Congress hold “public office” under § 1(3) and thus are ineligible for service on the IRC. This conclusion recognizes the evident purpose of § 1(3) to prevent self-interested officials from drawing the boundaries of their own electoral districts. Cf Ariz. Const, art. 4, pt. 2, § 1(15) (directing that “places of residence of incumbents or candidates shall not be identified or considered”).
¶ 31 Our interpretation of § 1(3) also recognizes the difference between its language and § l(13)’s reference to “Arizona public office.” Although Arizona may exclude members of Congress or other federal officeholders from serving on the IRC, § 1(13) recognizes that the state has no power to disqualify candidates from serving in federal office or offices created by other sovereign entities. See State ex rel. Pickrell v. Senner, 92 Ariz. 243, 246-47, 375 P.2d 728, 729-30 (1962); see also U.S. Term Limits, Inc. v. Thornton, 514 U.S. 779, 783, 115 S.Ct. 1842, 131 L.Ed.2d 881 (1995); State v. Osborne, 14 Ariz. 185, 207, 125 P. 884, 893-94 (1912) (recognizing power of Congress to fix time for election of representatives contrary to state constitution); Op. Ariz. Att’y Gen. 107-011, 2007 WL 4401306 (Dec. 5, 2007) (concluding that § 1(13) applies only to Arizona state and local offices given different phrasing in § 1(3) and because state cannot add to qualifications for federal office).
D.
¶ 32 Our conclusion that members of Congress hold “public office” for purposes of § 1(3) does not, however, resolve whether Bender, a tribal judge, holds a public office. Is a tribal office a public office under § 1(3)?
¶ 33 Petitioners argue that a tribal judgeship is a “public office” because the term generally refers to a position in which a person exercises a government’s sovereign powers and Indian tribes are sovereign entities. Citing dictionary definitions of “public office,” the dissent similarly argues that § 1(3) should be construed broadly to include tribal officers.
¶ 34 These arguments are not persuasive because they seek to interpret “public office” without considering the context in which it appears within § 1(3) and the way in which this phrase has otherwise been interpreted under Arizona law. As Justice Scalia has observed, it is a “fundamental principle of statutory construction (and, indeed, of language itself) that the meaning of a word cannot be determined in isolation, but must be drawn from the context in which it is used.” Deal v. United States, 508 U.S. 129, 132, 113 S.Ct. 1993, 124 L.Ed.2d 44 (1993). The same proposition applies in construing our constitution. See Corp. Comm’n v. Pac. Greyhound Lines, 54 Ariz. 159, 170, 94 P.2d 443, 447 (1939) (observing that constitutional provisions must be construed in light of the “instrument as a whole”); cf. NLRB v. Federbush Co., 121 F.2d 954, 957 (2nd Cir.1941) (L. Hand, J.) (noting that “[wjords are not pebbles in alien juxtaposition; they have only a communal existence; and not only does the meaning of each interpenetrate the other, but all in their aggregate take their purport from the setting in which they are used”).
¶ 35 Indian tribes are not, of course, political subdivisions of the state. Instead, Indian tribes have been recognized since the ratification of the United States Constitution as having a special sovereign status separate from the federal government and the states. Cf. U.S. Const, art. I, § 8, cl. 3 (granting Congress the power “[t]o regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes”). “Indian tribes retain attributes of sovereignty over both their members and their territory, to the extent that sovereignty has not been withdrawn by federal statute or treaty.” Iowa Mut. Ins. Co. v. LaPlante, 480 U.S. 9, 14, 107 S.Ct. 971, 94 L.Ed.2d 10 (1987) (citation and internal quotation marks omitted).
¶ 36 Consistent with the tribes’ distinctive status, Arizona’s constitution and laws generally do not include tribes within the meaning of the word “public.” Cf. Ariz. Const, art. 20, [136]*136par. 4 (referring separately to “public lands” and “lands ... owned or held by ... Indian tribes”). As noted above, see supra ¶¶ 23-29, Arizona’s constitution and statutes refer in many places to public office or public officers (for example, in provisions governing recall or financial disclosure), but none of those provisions has been construed to embrace tribal offices. Indeed, at oral argument, counsel could not identify any instance in Arizona law in which the word “public” has been interpreted to refer to Indian tribes.
¶ 37 Petitioners and the congressional ami-ci also contend that a tribal judge is a “public officer” under the test adopted in Winsor v. Hunt, 29 Ariz. 504, 520-21, 243 P. 407, 413 (1926). Winsor concerned a constitutional prohibition on state legislators being appointed or elected during their term to “any civil office of profit under this State” created during their term. (This provision was later replaced by a 1938 amendment adopting the language now in Article 4, Part 2, Section 5.) The Court concluded that the prohibition applied to “public officers” but not mere “employees.” Winsor, 29 Ariz. at 517, 243 P. at 412.
¶ 38 Recognizing that “[tjhere is no entirely satisfactory definition” of public office, id. at 518, 243 P. at 412, the Court in Winsor said a position is presumably an office, rather than employment, if (1) the specific position is created by law, (2) there are “definite duties imposed by law on the incumbent,” and (3) the duties “involve the exercise of some portion of the sovereign power.” Id. at 520-21, 243 P. at 413.
¶ 39 Winsor is inapposite. It construed a since-replaced constitutional provision and did not purport to adopt a general definition of “public office.” But most importantly, Winsor did not concern whether an individual held a “public” position (Winsor indisputably worked for the state), but instead whether the person was an officer rather than an employee. Although we do not question Winsofs criteria for identifying when a position created by state law qualifies as an “office of profit under this State,” or that those criteria might provide useful guidance in other contexts, of. McCarthy v. State ex rel. Harless, 55 Ariz. 328, 336, 101 P.2d 449, 452 (1940) (observing that position on a county welfare board was an “office” under Win-sor in construing statute concerning eligibility to serve as county supervisor), we decline to use them to define “public office” for purposes of § 1(3).
¶ 40 In arguing that “public office” as used in § 1(3) includes tribal judges, Petitioners also contend that Indian tribes are “communities of interest” affected by redistricting and that allowing tribal officers to serve as commissioners would undermine the goals of promoting impartiality and public confidence in the redistricting process. These arguments are not compelling. Section 1(3) does not exclude persons from service as commissioners merely because they may be associated with some group characterized as a community of interest. Indeed, § 1(3) does not exclude many persons who might be regarded as potentially interested or biased in the redistricting process, such as relatives or staff members of incumbents or prospective candidates.
¶ 41 Moreover, we are confident that the Appointment Commission will carefully exercise its constitutional responsibility to identify nominees, who are committed to serving “in an honest, independent and impartial fashion and to upholding public confidence in the integrity of the redistricting process.” Ariz. Const, art. 4, pt. 2, § 1(3). Here, there is no reason to question the Appointment Commission’s conclusion that Bender, despite his service as a tribal judge, could serve impartially and uphold public confidence in the integrity of the process.
¶ 42 Before § 1(3) was adopted, the Arizona Constitution had referred to “public office” or “public officers” in a half dozen places, none of which was ever construed to include tribal officers. As noted above, no legal authority identified by the parties or this Court has interpreted a state law referring to “public office” as including tribal offices absent a specific statutory reference to Indians or tribes. For this Court to construe § 1(3) as including tribal offices would thus constitute a unique and unprecedented interpretation of the phrase “public office.” Since statehood, this Court has declined to construe provisions restricting eligibility for [137]*137public office more broadly than the constitution’s text requires. See Steeves v. Wilson, 14 Ariz. 288, 290, 127 P. 717, 717-18 (1912) (concluding that although Article 7, Section 15 requires office holders to be qualified electors, it does not require that they vote at election held to fill the office). We decline to do so again today.
¶ 43 Because § 1(3) contains no language indicating that its proscription on commissioners holding “other public office” extends to Indian tribes, we hold that the position of tribal judge is not a “public office” for purposes of § 1(3).
IV.
¶ 44 For the reasons stated, we accepted jurisdiction and granted relief in part. Because Schnepf and Sossaman are ineligible to serve .as commissioners, we ordered the Appointment Commission promptly to identify two alternative nominees so that Adams could appoint the initial commissioner from a pool of twenty-five qualified nominees. Petitioners’ request for relief was denied as to Bender because his position as a tribal judge does not render him ineligible to serve as a commissioner.
CONCURRING: ANDREW D. HURWITZ, Vice Chief Justice and MICHAEL D. RYAN, Justice (Retired).