*410OPINION
By the Court,
Parraguirre, C.J.:In this appeal, we are asked to define the eligibility requirements set forth in NRS 4.010(2)(a) for justice of the peace. Based on the statute’s plain and unambiguous language, we conclude that, before being elected or appointed to a justice of the peace position, an attorney must be licensed to practice law for a minimum of five calendar years, which are typically 365-day years, from the date of his or her admission. After expedited briefing and argument, we summarily affirmed the district court’s order granting the petition to remove the candidate for justice of the peace from the ballot, as she did not meet the minimum five-year requirement. This opinion sets forth the full reasoning that underlies our disposition.
BACKGROUND
Appellant Amber Lynn Candelaria graduated from the University of Nevada, Las Vegas, Boyd School of Law, in 2006. After successfully passing the Nevada State Bar exam that same year, she was licensed and admitted to practice law for the first time when she was admitted to the Nevada State Bar on October 17, 2006.
In November 2009, the State Bar sent Candelaria her 2010 bar membership fees statement, which assessed her fees at the rate applicable to active attorneys admitted to practice in any jurisdiction for five or more years. After receiving this statement, in January 2010, Candelaria filed a declaration as a candidate for election to the office of justice of the peace in Department 14 of Las Vegas Township. The election for this office was scheduled to be held on November 2, 2010.
Shortly after Candelaria filed her candidacy declaration, respondent Clark County District Attorney David Roger received a *411request to challenge Candelaria’s eligibility to run for the office from real party in interest Bernard Brownislaw Zadrowski, who has also declared his candidacy for this position. As authorized by statute, Roger filed a petition in the district court challenging Candelaria’s eligibility. In resolving the petition, the district court determined that Candelaria did not meet NRS 4.010(2)(a)’s requirement that she have been “licensed and admitted to practice law in the courts of this State, another state or the District of Columbia for not less than 5 years at any time preceding . . . her election or appointment.” The district court further rejected Candelaria’s constitutional challenges to NRS 4.010(2)(a). As a result, the district court entered an order granting the petition to remove Candelaria from the ballot as a candidate for justice of the peace. This appeal followed.
DISCUSSION
This court presumes statutes to be valid, and to demonstrate that a statute is unconstitutional, the challenger must clearly show the statute’s invalidity. Halverson v. Secretary of State, 124 Nev. 484, 487-88, 186 P.3d 893, 896 (2008). Questions of statutory construction are reviewed de novo. Leven v. Frey, 123 Nev. 399, 402, 168 P.3d 712, 714 (2007). If a statute’s language is clear and the meaning plain, this court will enforce the statute as written. We the People Nevada v. Secretary of State, 124 Nev. 874, 881, 192 P.3d 1166, 1170-71 (2008). Statutory language is ambiguous if it is capable of more than one reasonable interpretation. Id. at 881, 192 P.3d at 1171; Leven, 123 Nev. at 404, 168 P.3d at 716. Under this framework, we first interpret NRS 4.010(2)(a)’s meaning, before addressing the constitutional issues presented.
Statutory interpretation
Nevada’s Constitution gives the Legislature the power to determine the number of justices of the peace to be elected in each city and township in the state and to “fix by law their qualifications” for holding the office. Nev. Const, art. 6, § 8. To that end, the Legislature has enacted NRS 4.010, which prescribes the qualifications for service as a justice of the peace. Under NRS 4.010(2)(a), in counties with populations of 400,000 or more, a justice of the peace in a township with a population of 100,000 or more must be
an attorney who is licensed and admitted to practice law in the courts of this State at the time of his or her election or appointment and has been licensed and admitted to practice law *412in the courts of this State, another state or the District of Columbia for not less than 5 years at any time preceding his or her election or appointment.
Candelaria contends that the term “years” is ambiguous because the statute does not define it and this court’s precedent has found the term to be ambiguous. We disagree.
NRS 4.010(2)(a)’s five-year admission and licensure requirement is plain and unambiguous
In support of her ambiguity argument, Candelaria points to this court’s decision in SNEA v. Lau, 110 Nev. 715, 877 P.2d 531 (1994). In SNEA, this court addressed a challenge to former governor Bob Miller’s eligibility to run for a second full term under Article 5, Section 3 of the Nevada Constitution, which prohibits an individual acting as governor for “more than two years” from being elected as governor more than once. 110 Nev. at 716-17, 877 P.2d at 532-33. Miller had served one full term and a partial term after taking over for Richard Bryan, who was elected to the United States Senate during his term as governor. Id. at 717, 877 P.2d at 532-33. The determinative issue in that case was this court’s interpretation of the meaning of the term “years” as used in the phrase “more than two years” in Article 5, Section 3. Id. at 716-17, 877 P.2d at 532-33.
In addressing this issue, the court rejected the petitioners’ argument that the term “years” clearly and unambiguously meant a 365-day calendar year. Id. at 717, 877 P.2d at 533. The court began its analysis by noting that many words in the English language can have two or more meanings. Id. The court then concluded that the use of the word “years” in Nevada’s statutes and Constitution was an example of this phenomenon, and the court observed that the word may mean a calendar-based year, which is calculated from and to a set date, or an official or political year, which runs from and to a floating day within a month.2 Id. at 718, 877 P.2d at 533. Ultimately, the court concluded that the term “years,” as used in Article 5, Section 3, should be interpreted as official years. Id. at 719, 877 P.2d at 534.
Candelaria relies on SNEA to support her contention that there is no language in NRS 4.010(2)(a) that clearly indicates that five calendar, and typically 365-day years, must have elapsed between the date of licensure and the date of the election, or that otherwise articulates a specific period during which a candidate for justice of the peace must have been licensed and admitted to practice law to *413be eligible to run for that position. Candelaria asserts that NRS 4.010(2)(a) does not require her to have been licensed or admitted for a particular period of time, but merely requires that she have been licensed and admitted a certain number of “calendar years.”3
Candelaria’s arguments are problematic for a number of reasons. As an initial matter, the language of the statute at issue here is significantly different and far more specific than the constitutional provision at issue in SNEA. The language of Article 5, Section 3 provides no guidance on what is meant by “years” as used in the phrase “two years of a term.” In contrast, NRS 4.010(2)(a) requires a candidate for justice of the peace to have been “licensed and admitted to practice law ... for not less than 5 years at any time preceding his or her election or appointment.” As Zadrowski points out, the “not less than 5 years” language anticipates that the attorney will have been licensed and admitted for an exact period of time equal to not less than five years. Moreover, he correctly notes that the statute provides a specified date by which this five-year period must have concluded — before the attorney’s election or appointment to the position. Because the statute provides a specific end date, it most logically follows that there is also a specified beginning date — the date an attorney first becomes licensed.
As pointed out in SNEA, many words, viewed in isolation, can have multiple meanings. 110 Nev. at 717, 877 P.2d at 533. By focusing exclusively on the term “years,” Candelaria overlooks other key phrasings in NRS 4.010(2)(a). The statute modifies the term “years” with “for not less than 5 years at any time preceding his or her election or appointment.” NRS 4.010(2)(a) (emphases added). Unlike the usage of the term “years” in SNEA, the usage of that term in NRS 4.010(2)(a) is not susceptible to more than one reasonable interpretation. Here, the statute’s language anticipates a definite period (not less than five years) and sets a definite beginning date (the date of admission and licensure) and a date by which the period must be completed (prior to the attorney’s election or appointment to the position of justice of the peace). Thus, the period of not less than five years must begin and end before the attorney’s election or appointment to the position, a conclusion that requires the use of a calendar-year approach. See SNEA, 110 Nev. at 718, 877 P.2d at 533 (defining a calendar-based year to mean a year calculated from and to a set date). It therefore fol*414lows that NRS 4.010(2)(a), by its plain language, requires an attorney to have been licensed for a minimum of five calendar years, which are typically 365-d’ay years, from the date of his or her admission before being elected or appointed to the justice of the peace position.
In light of NRS 4.010(2)(a)’s plain and unambiguous language, Candelaria was required to have been licensed and admitted for five calendar years by the November 2010 election. Candelaria was licensed and admitted to practice law for the first time when she was admitted to the Nevada State Bar on October 17, 2006. As a result, at most; she will have been licensed and admitted for four years by the time of the November 2010 election. Thus, she is ineligible to serve as a justice of the peace in Las Vegas Township based on her failure to meet the minimum statutory requirement.4 Accordingly, to the extent Candelaria raises statutory construction challenges, we affirm the district court’s order granting the petition to remove Candelaria from the ballot as a justice of the peace candidate. We now turn to Candelaria’s constitutional arguments.
Constitutional challenges to NRS 4.010(2) (a)
Candelaria challenges the constitutionality of NRS 4.010(2)(a) on two grounds: (1) that it interferes with the electorate’s right to vote for the candidate of its choice and her right to run for public office, and (2) that it violates equal protection.5
*415Before discussing these constitutional issues, we address a procedural irregularity that is presented in this- appeal. Specifically, Candelaria has failed to comply with NRAP 44. Under NRAP 44, when a party challenges the constitutionality of a legislative act in a proceeding before this court and in which the state is not a party, the party asserting the challenge must give written notice to the clerk of this court, so that the clerk can certify the fact to the attorney general. Here, Candelaria did not provide the clerk with written notice of the constitutional challenge. Although counsel for Candelaria, upon questioning, stated during oral argument that such notice was provided to the court, our review of the documents submitted to this court reveals that no such notice was provided. This failure is an independent basis upon which to summarily reject her constitutional arguments. But because these issues concern important constitutional questions, of which our resolution does not render the statute unconstitutional, we elect, in this case, to address the merits of these arguments. Cf. Hamm v. Arrowcreek Homeowners’ Ass’n, 124 Nev. 290, 300, 183 P.3d 895, 903 (2008) (noting that this court may address significant, though unpreserved, constitutional issues).
NRS 4.010(2) (a) is not an invalid restriction on the constitutional election rights of the electorate or candidates
Candelaria contends that NRS 4.010(2)(a) is unconstitutional because it interferes with the electorate’s right to vote for the candidate of its choice and because she has a right to run for public office. Roger and Zadrowski disagree, both arguing that reasonable regulation of elections and restrictions on candidate eligibility, particularly in the judicial context, have long been upheld and that there is nothing unreasonable in requiring justices of the peace in urban areas to be licensed and admitted for at least five years.
This court has previously addressed the implications of candidate eligibility requirements on basic constitutional rights in Nevada Judges Ass’n v. Lau, 112 Nev. 51, 55, 910 P.2d 898, 900-01 (1996). In that case, the court, by quoting Anderson v. Celebrezze, 460 U.S. 780, 787 (1983), noted that two separate but overlapping rights, which “ ‘rank among our most precious freedoms,’ ” “ ‘the right of individuals to associate for the advancement of political beliefs’ ” and “ ‘the right of qualified voters . . . to cast their votes effectively’ ” are implicated by the enactment of candidate eligibility requirements. Nevada Judges, 112 Nev. at 55, 910 P.2d at 901. The Nevada Judges court explained that, while the United States Supreme Court has labeled the rights of voters “fundamental,” it has also declared that the states may place restrictions on individuals’ eligibility to appear on the ballot *416as candidates. 112 Nev. at 56, 910 P.2d at 901 (quoting Anderson, 460 U.S. at 788). The Nevada Judges court concluded that a proposed ballot initiative that barred judges from seeking more than two terms on the same court was not an unconstitutional restriction on the rights of the voters or the candidates. 112 Nev. at 53-56, 910 P.2d at 900-01. The court focused its analysis on the state interests at stake. Id. at 56, 910 P.2d at 901. After expressing some initial skepticism over the wisdom of the proposed initiative, given the loss of experience that would result from the provision’s passage, the court nevertheless acknowledged that the measure could also broaden the composition of the judiciary, encourage new candidates to come forward, eliminate unfair advantages provided incumbents, and discourage entrenchment of power bases in the judiciary. Id. at 57, 910 P.3d at 902. The court determined that the potential benefits were legitimate and that it was not the role of the court to pass on the wisdom of the initiative. Id.
The requirement here is far less restrictive than the Nevada Judges initiative, since NRS 4.010 only requires that candidates wait a certain period of time rather than possibly acting as a permanent ban after a certain period in office and is presumably of much greater legitimate interest than the initiative in Nevada Judges. NRS 4.010(2)(a) simply requires five years’ experience before becoming a judge in a highly populated township, which is a legitimate state interest. Thus, Candelaria’s first constitutional argument fails.
NRS 4.010(2) (a)’s establishment of different eligibility requirements for the office of justice of the peace in urban and rural areas does not violate equal protection •
Candelaria argues that NRS 4.010(2)(a) violates her equal protection rights under the United States and Nevada Constitutions by improperly creating different and disparate requirements for justices of the peace based on the population of the county and township in which the justice of the peace will serve.
The Fourteenth Amendment of the United States Constitution forbids an enactment that “den[ies] . . . any person . . . equal protection of the laws.” U.S. Const, amend. XIV, § 1. Article 4, Section 21 of the Nevada Constitution requires that all laws be “general and of uniform operation throughout the State.” “The standard for testing the validity of legislation under the equal protection clause of the state constitution is the same as the federal standard.” Barrett v. Baird, 111 Nev. 1496, 1509, 908 P.2d 689, 698 (1995), overruled on other grounds by Lioce v. Cohen, 124 Nev. 1, 174 P.3d 970 (2008). A statute that treats similarly situated people differently implicates equal protection. Rico v. Rodriguez, *417121 Nev. 695, 703, 120 P.3d 812, 817 (2005). When a suspect class or fundamental right is not involved, different classifications are permissible, so long as they are reasonable. Flamingo Paradise Gaming v. Att’y General, 125 Nev. 502, 520, 217 P.3d 546, 558-59 (2009). This court has recognized that restrictions on candidacy do not, by themselves, necessarily compel strict scrutiny under the equal protection clause. Nevada Judges, 112 Nev. at 56, 910 P.2d at 901. Therefore, NRS 4.010(2)(a) will be upheld as constitutional and providing reasonable classifications if there is a rational basis related to a legitimate government interest for establishing heightened qualifications for justices of the peace in this state’s most densely populated areas. Rico, 121 Nev. at 703, 120 P.3d at 817.
As indicated by Zadrowski, justices of the peace in highly populated areas are likely to have busier dockets than their counterparts in more rural areas, and increased education and experience requirements are a rational way to advance the governmental interest in attempting to identify individuals likely to succeed under particularly, demanding and fast-paced workloads. Thus, NRS 4.010(2)(a) has a legitimate purpose, and its classification between urban and rural justices of the peace is rationally related to achieving that purpose. See Allen v. State, Pub. Emp. Ret. Bd., 100 Nev. 130, 136, 676 P.2d 792, 795-96 (1984) (stating that this court will not overturn legislation unless the treatment of different groups “ ‘is so unrelated to the achievement of any combination of legitimate purposes that [this court] can only conclude that the legislature’s actions were irrational’ ” (quoting Vance v. Bradley, 440 U.S. 93, 97 (1979))); see also Goodson v. State, 115 Nev. 443, 991 P.2d 472 (1999) (rejecting an argument that NRS 4.010’s permission of nonlawyers to preside over criminal trials for offenses punishable by jail sentences in rural areas violates equal protection or due process). Accordingly, NRS 4.010(2)(a) satisfies the equal protection clauses of the United States and Nevada Constitutions.
CONCLUSION
In sum, the plain language of NRS 4.010(2)(a) anticipates a particular, consistent start date to the running of the five-year period that expressly terminates on the election, and that the admission date is the most reasonable date to use as beginning the period. Therefore, under the language of NRS 4.010(2)(a), Candelaria fails to meet the five-year minimum requirement. Further, we reject Candelaria’s constitutional challenges to NRS 4.010(2)(a), concluding that the statute does not interfere with the electorate’s right to vote for the candidate of its choice and her right to run for office; nor does it violate equal protection.
Hardesty, Douglas, and Pickering, JJ., concur.An example of a political or official year is one that begins and ends on a Monday and can therefore vary between 52 weeks or 53 weeks. SNEA, 110 Nev. at 718, 877 P.2d at 533-34.
To reach the required five years using the approach Candelaria advocates, 2006 must be counted as a full year of licensure and admission, even though Candelaria was only admitted in October of that year, and therefore was licensed for only three months in 2006. Under this scenario, 2006 actually is added to 2007, 2008, and 2009 to reach four years. Finally, this year — 2010— would likewise have to be treated as a full year of licensure and admission, even though the election is scheduled for November of this year.
In an apparent effort to avoid the application of NRS 4.010(2)(a)’s plain language, Candelaria attempts to create an ambiguity argument by relying on Supreme Court Rule 98, which addresses issues related to bar membership, including setting the amount of membership fees. Candelaria argues that because the State Bar has concluded that she has been “admitted to practice . . . 5 years or more,” for the purpose of calculating her membership fees under SCR 98(9), NRS 4.010(2)(a) is ambiguous and susceptible to more than one reasonable interpretation with regard to when an attorney can be said to have satisfied the “licensed and admitted to practice ... for not less than 5 years” requirement set forth in that statute. But neither SCR 98 nor the State Bar’s determination regarding Candelaria’s status for the purpose of calculating her membership fee responsibilities are in any way relevant to determining the meaning of NRS 4.010(2)(a)’s five-year requirement. As a result, we reject as without merit Candelaria’s efforts to create ambiguity where none exists with regard to NRS 4.010(2)(a)’s five-year requirement.
Candelaria also argues that NRS 4.010(2)(a) violates her due process rights and was enacted in violation of both separation of powers and Article 4, Section 17 of the Nevada Constitution’s single-subject rule. These arguments were not made in district court or developed with sufficient authority on appeal, and consequently, we will not substantively address them in this opinion. Cf. Levingston v. Washoe Co., 112 Nev. 479, 482-83, 916 P.2d 163, 166 (1996) (recognizing that it is within this court’s authority to address constitutional issues raised for the first time on appeal); see Edwards v. Emperor’s Garden Rest., 122 Nev. 317, 330 n.38, 130 P.3d 1280, 1288 n.38 (2006) (noting that this court need not consider an issue not cogently argued or supported by salient authority).