OPINION
¶ 1 Appellant Eller Media Co. (Eller) 1 brоught this action to enjoin appellee City of Tucson from enforcing a provision in its Outdoor Lighting Code (OLC) that prohibits bottom-mounted lights on billboards. Eller appeals the trial court’s order granting summary judgment in favor of the City on its claims that the prohibition violates its substantive due process and equal protection rights. Because we find that Eller’s constitutional claims fail as a matter of law, we affirm the trial court’s order.
Facts and Procedural History
¶2 A detailed history of this case is set forth in our decision in
Whiteco Outdoor Advertising v. City of Tucson,
*130 ¶ 3 Eller then filed this action in superior court, requesting that the court enjoin thе City from enforcing the OLC provision and seeking a declaratory judgment that the provision violates its substantive due process and equal protection rights. After the parties filed cross motions for summary judgment, the trial court granted Eller’s motion for pаrtial summary judgment, concluding that the OLC was a zoning ordinance, that Eller’s use of bottom-mounted lighting on its billboards was a protected nonconforming use, and that the prohibition against the use was therefore unenforceable. Having found in favor of Eller on this ground, the trial court did not address the constitutional claims. On appeal, we vacated the trial court’s order, concluding it erred in ruling that the City’s OLC was a zoning ordinance and that the nonconforming use statute precluded it from prohibiting Eller’s use of bottom-mounted lights. See Whiteco Outdoor Advertising. On remand, the trial court found that, under the rational basis test, Eller had failed, as a matter of law, to establish that the OLC provision violated either its substantive due process or equal protection rights. Accordingly, the court granted the City’s motion for summary judgment on El-ler’s constitutional claims and this appeal followed.
Discussion
¶ 4 On appeal from the trial court’s grant of summary judgment, we review de novo whether there are any genuine issues of material fact and whether the trial court erred in applying the law.
Prince v. City of Apache Junction,
¶5 Because the provision at issue here does not affect the advertising message Eller displays on its billboards, it does not affect an aspect of communicative speech; consequently, it does not affect or burden any fundamental right, including those granted by the First Amendment.
See Ruiz v. Hull,
a. Substantive due process
¶ 6 Under the rational basis test, we must uphold a law or regulation against a
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claim that it violates substantive due process if it does not transgress “‘some
basic and fundamental principle,”’ Wallace v. Casa Grande Union High School Dist. No. 82,
¶ 7 Although Eller seems to challenge both the principle that upward-shining lights emit more rays into the night sky than do those that shine downward and the City’s claim that requiring top-mounted lights will reduce skyward emissions, the record does not appear to support those claims. Further, in an apparent abandonment of those positions, Eller argues simply that the City can achieve a similar or greater emission reduction by requiring that bottom-mounted lights be shrouded with a “prototype shield” its expert witness’s company has developed. Even if this were true, however, and notwithstanding that Eller obviously prefers this means to reduce its billboards’ emissions, under the rational basis test, the means the state choоses to achieve a particular goal need not be the most effective or least onerous available. The means need only rationally further that goal; that is, have a real and substantial relation to the achievement of the goal.
Compare American Fed’n of Labor
(under rational basis test, courts do not review whether law is wise or whether legislature has adopted best means to achieve its purpose)
with Mountain States Tel. and Tel. Co. v. Arizona Corp. Comm’n,
b. Equal protection
¶ 8 Under the rational basis test, we will uphold a law or regulation that imposes a burdеn on one class but not another if the legislation serves a legitimate state interest and the facts support the conclusion that the classification rationally furthers that interest. Kenyon. Because Eller does not challenge the legitimacy of the City’s stated goal of enhancing astronomical observations, we address only the second requirement.
¶ 9 The guarantee of equal protection is violated only if a classification rests on grounds wholly irrelevant to the achievemеnt of the state’s objective.
Id. A
regulation that
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applies to some members of a class and not to others will be upheld if the classification is not arbitrary and there is a substantial difference between those within and without the class.
Farmer v. Killingsworth,
¶ 10 Eller asserts that, because it presented below its expert witness’s calculations and conclusions establishing that a typical outdoor display lot 3 lighting fixture permits more light to be reflected into the night sky than that permitted by either a top-mounted or a “well-shielded” bottom-mounted billboard lighting fixture, it raised a genuine issue of material fact that should have precluded summary judgment on its equal protection claim. Although we question whether those calculations, some of which were admittedly based on “estimates and assumptions,” were sufficiently reliable so as to raise a genuine issue of material fact, there can be little doubt that other outdoor light sources, including some display lots, in the city emit more light into the night sky than do single billboards. However, we fail to see, nоr does Eller explain, how this fact is material to its claim that enforcing the OLC provision at issue violates its equal protection rights.
¶ 11 Eller does not contend that other outdoor light sources are allowed to use bottom-mounted lighting while the OLC provision at issue prohibits it from doing so. Indeed, because the OLC appears to require that display lot lights, like billboard lights, must generally shine downward, 4 we agree with the City that there appears to be little practical difference between the requirements imposed on the two light sources. Rather, Eller appears to argue simply that the OLC, as a whole, permits other light sources to emit more light into the night sky than do billboards. Assuming that Eller’s expert witness’s calculations are correct, however, the OLC would be discriminatory, that is, it would allow other light sources to emit more light into the night sky than do billboards, regardless of whether it permitted top-mounted or bottom-mounted light fixtures, or both.
¶ 12 Moreover, we find untenable Eller’s apparent contention that the City cannot regulate its billboard light output unless and until its emissions equal those produced by “other outdoor lighting users, such as auto sales display lots and recreational sports facilities.” This suggestion would preclude the City from regulating all but the brightest bulb in the night sky. Indeеd, it presumes that all light sources should and must emit the same amount of light. Eller’s own expert witness recognized, however, that display lot lights, as an example, are typically more powerful than those on billboards because they must “generate high illuminаtion over a relatively large area of a display lot.” Accordingly, given the undisputedly different lighting requirements of display lots and billboards, Eller has failed to establish as arbitrary the City’s allegedly disparate treatment between the two outdoor light sоurces. Farmer.
¶ 13 Eller’s equal protection claim, like its substantive due process claim, fails as a matter of law. We therefore conclude that the trial court correctly granted the City’s motion for summary judgment on both claims. Prince.
Notes
. Formerly Whiteco Outdoor Advertising, Inc.
.
See Lutz v. City of York, Pennsylvania,
. The OLC lists as examples of display lots those at which automobiles, recreational vehiсles, or building materials are sold or rented.
. The OLC requires that display lot lighting fixtures must either be fully shielded, thus permitting no light rays to be emitted at an angle above the horizontal plane of the fixture, or be designed or provided with sharp cut-off capability, so as to minimize up-light, spill-light, and glare.
