UPON REHEARING EN BANC
D. ARTHUR KELSEY, Judge.The trial court convicted Sharon Boyd, an erotic dancer, of violating Henrico County’s public nudity ordinance. The two owners of the strip club, Dianna Lee White and Donna Jean White, were convicted of aiding and abetting Boyd’s violation. They now appeal, claiming their misdemeanor convictions *503should be overturned on various theories. A divided panel of our Court vacated all three convictions. Boyd v. County of Henrico, 41 Va.App. 1, 581 S.E.2d 863 (2003). Having reconsidered the matter en banc, we reject appellants’ challenge to the public nudity ordinance and affirm their convictions.
I.
Henrico enacted its public nudity ordinance in 1982. Its text tracks the language of similar public nudity ordinances adopted across the Commonwealth.1 The Henrico County Board of Supervisors explained its legislative intent in enacting the ordinance this way:
The purpose of this ordinance is to make unlawful displays of public nudity in the County, which are deemed offensive to public morality and injurious to the health, safety and general welfare of County citizens, regardless of whether such nudity would or would not in any specific instance be deemed obscene. The ordinance contains exceptions for *504exhibitions and other performances in institutions or establishments, such as theaters and concert halls, primarily devoted to expressions of opinion, communication, speech, ideas, information, art or drama. The ordinance is based on similar legislation enacted in York County and the City of Virginia Beach,2 to mention two examples.
Since 1982, thirty-eight individuals had been prosecuted under the public nudity ban. This one case involves the only application of the ordinance against erotic dancers.
On July 6, 2001, officers from the Henrico County Police Department went to a newly opened erotic club named Gold City Showgirls. While there, the officers observed ten female dancers strip down to “pasties” and “G-strings” in exchange for tips. The officers issued summonses to the ten dancers they observed, including Boyd, for violating the public nudity ordinance and to a club manager, Donna White, for aiding and abetting the violations.3 On July 8, 2001, the officers returned and observed the same type of semi-nude dancing. The officers issued a summons to Dianna White, the manager on duty, and a second summons to Boyd.
After being found guilty in general district court, appellants appealed to circuit court. In the meantime, the owners of Gold City and two erotic dancers filed a civil action in United States District Court for the Eastern District of Virginia asserting that the ordinance should be declared unconstitutional and the state prosecution enjoined. The federal district court abstained from ruling on this issue. Colonial *505First Props., LLC v. Henrico County Virginia, 166 F.Supp.2d 1070 (E.D.Va.2001). The state circuit court ease went to trial in late 2001. The parties to the criminal case agreed that depositions taken in the federal case could be submitted de bene esse to the state court. The parties, however, did not agree to submit to the state trial court the transcript of the federal court proceeding. Nor did they stipulate to any factual findings made by the federal district court during the abstention hearing.4
The trial court rejected appellants’ constitutional challenges and heard the cases on the merits. At trial, appellants admitted the dancers wore “pasties” and “G-strings” on July 6 and July 8, 2001. The dancers conceded that their state of undress violated the public nudity ordinance, but instead claimed that their striptease act fell within the exemption in the ordinance for the performance of “any play, ballet, drama, tableau, production or motion picture” in a theater, concert hall, or the like. Henrico County Code § 13 — 107(c).5 After hearing testimony from eight dancers and the two owners of *506Gold City, the trial court found as a fact that Gold City was not a “theater” under the ordinance and the dancers were not engaged in any “theatrical performance either.”
II.
Appellants challenge the public nudity ordinance on various grounds. They contend that (a) the public nudity ordinance infringes on their First Amendment right to erotic dancing; (b) the ordinance should be declared void for vagueness; (c) the County violated equal protection principles by selectively enforcing the ordinance against them; (d) the County has no delegable authority from the General Assembly to enact this ordinance; and (e) the evidence proves their entitlement to the theater exemption to the ordinance.6
We begin our analysis with basic principles of judicial review. All legislative acts are “presumed to be constitutional.” In re Phillips, 265 Va. 81, 85, 574 S.E.2d 270, 272 (2003); see also Bosang v. Iron Belt Bldg. & Loan Ass’n, 96 Va. 119, 123, 30 S.E. 440, 441 (1898); Johnson v. Commonwealth, 40 Va.App. 605, 612, 580 S.E.2d 486, 490 (2003) *507(recognizing that every legislative act “is presumed to be constitutional, and the Constitution is to be given a liberal construction so as to sustain the enactment in question, if practicable”). This presumption is “one of the strongest known to the law.” Harrison v. Day, 200 Va. 764, 770, 107 S.E.2d 594, 598 (1959). Under it, courts must “resolve any reasonable doubt” regarding the constitutionality of a law in favor of its validity. In re Phillips, 265 Va. at 85, 574 S.E.2d at 272; see also Wayside Rest., Inc. v. Virginia Beach, 215 Va. 231, 236, 208 S.E.2d 51, 55 (1974) (holding public nudity ordinance constitutional). “To doubt is to affirm.” Peery v. Bd. of Funeral Dirs., 203 Va. 161, 165, 123 S.E.2d 94, 97 (1961) (quoting City of Roanoke v. Elliott, 123 Va. 393, 406, 96 S.E. 819, 824 (1918)).
A. The Public Nudity Ordinance Does Not Violate The First Amendment.
Statutes prohibiting public nudity are of “ancient origin” and “reflect moral disapproval of people appearing in the nude among strangers in public places.” Barnes v. Glen Theatre, Inc., 501 U.S. 560, 568, 111 S.Ct. 2456, 2461, 115 L.Ed.2d 504 (1991) (plurality). For this reason, it has been the traditional view that whatever natural law construct exists to support the “right to appear au naturel at home,” that right is “relinquished when one sets foot” outside. Richards v. Thurston, 424 F.2d 1281, 1285 (1st Cir.1970).7 Even so, in the “outer ambit” of constitutional theory, the erotic speech component of a particular form of public nakedness — nude dancing at strip *508clubs — receives “some measure” of First Amendment protection. Erie v. Pap’s A.M., 529 U.S. 277, 289, 120 S.Ct. 1382, 1391, 146 L.Ed.2d 265 (2000) (plurality); see also Barnes, 501 U.S. at 566, 111 S.Ct. at 2460. The right, however, is hardly a robust one. At best, it receives a “diminished form of protection under the First Amendment,” Ben’s Bar, Inc. v. Village of Somerset, 316 F.3d 702, 707 (7th Cir.2003), because it involves the “barest minimum of protected expression,” Barnes, 501 U.S. at 565, 111 S.Ct. at 2460 (quoting Doran v. Salem Inn, Inc., 422 U.S. 922, 932, 95 S.Ct. 2561, 2568, 45 L.Ed.2d 648 (1975)). Put another way, the right is only “marginally” within the “outer perimeters” of the First Amendment. Barnes, 501 U.S. at 566, 111 S.Ct. at 2460.
Appellants claim the Henrico public nudity ordinance violates the marginal free speech rights inherent in erotic dancing. They rest this claim on two assertions. First, appellants contend the ordinance constitutes the most serious of all First Amendment violations: a content-based restriction on free speech.8 Second, appellants argue that the public nudity ordinance — even if not content based — still works such a hardship on their free speech rights that it must be declared unconstitutional. We reject both arguments, finding they reflect a basic misunderstanding of First Amendment law.
A law regulating expressive activity should be deemed content neutral “so long as it is ‘justified, without *509reference to the content of the regulated speech.’ ” Ward v. Rock Against Racism, 491 U.S. 781, 791, 109 S.Ct. 2746, 2753, 105 L.Ed.2d 661 (1989) (emphasis in original and citation omitted). Because such regulations are “unrelated to [the suppression of] expression,” Lorillard Tobacco Co. v. Reilly, 533 U.S. 525, 567, 121 S.Ct. 2404, 2428, 150 L.Ed.2d 532 (2001), they are subjected to a “less-rigorous analysis,” Turner Broad. Sys. v. FCC, 520 U.S. 180, 213, 117 S.Ct. 1174, 1198, 137 L.Ed.2d 369 (1997). Sufficient government interests justifying content-neutral regulations include “preventing harmful secondary effects,” Erie, 529 U.S. at 293, 120 S.Ct. at 1393, and “protecting order and morality,” Barnes, 501 U.S. at 569, 111 S.Ct. at 2462, both classic expressions of state police powers.
The Henrico public nudity ban regulates conduct — not the content of anyone’s speech. In this respect, the ordinance is no different from either of the two public nudity laws deemed content neutral in Barnes and Erie. As the United States Supreme Court said in Erie:
The ordinance here, like the statute in Barnes, is on its face a general prohibition on public nudity. By its terms, the ordinance regulates conduct alone. It does not target nudity that contains an erotic message; rather, it bans all public nudity, regardless of whether that nudity is accompanied by expressive activity.
Erie, 529 U.S. at 290, 120 S.Ct. at 1391. The same can be said of the Henrico ordinance.
True, some may “view restricting nudity on moral grounds as necessarily related to expression.” Barnes, 501 U.S. at 570, 111 S.Ct. at 2462. And, in an abstract sense, it is entirely fair to say that people “who go about in the nude in public may be expressing something about themselves by so doing.” Id. This point, however, proves too much. Taken to its logical limits, it obliterates any First Amendment distinctions between speech and conduct. A flasher in a public mall may genuinely intend to communicate a message — whether erotic, neurotic, or both. But the communicative element in his conduct should receive no constitutional protection. Despite *510the libertarian traditions animating the First Amendment, we are not dealing here with protecting the societal value of “untrammeled political debate” and “few of us would march our sons and daughters off to war to preserve a citizen’s right” to unlimited expression of public sexuality. Erie, 529 U.S. at 294, 120 S.Ct. at 1394 (quoting Young v. Am. Mini Theatres, Inc., 427 U.S. 50, 70, 96 S.Ct. 2440, 2452, 49 L.Ed.2d 310 (1976)).
Appellants take no issue with Erie or Barnes, but instead seek to distinguish them on the ground that the Henrico ordinance contains an exemption for theatrical performances. The public nudity ban in Erie, appellants argue, applied to theaters. From there, appellants reason that the theatrical nudity exemption in the Henrico ordinance transforms an otherwise permissible, content-neutral public nudity ban into a thinly disguised content-based restriction. We disagree.
Despite the fact that the public nudity ban in Erie did not include an express exemption, the prosecutor in Erie stipulated that the ban did not apply to theatrical and artistic nudity. Making the same argument as appellants do here, the dissent in Erie seized upon this stipulation:
In an earlier proceeding in this case, the Court of Common Pleas asked Erie’s counsel “what effect would this ordinance have on theater ... productions such as Equus, Hair, 0[h!] Caleutta[!]? Under your ordinance would these things be prevented ... ?” Counsel responded: “No, they wouldn’t, Your Honor.” App. 53. Indeed, as stipulated in the record, the city permitted a production of Equus to proceed without prosecution, even after the ordinance was in effect, and despite its awareness of the nudity involved in the production----As presented to us, the ordinance is deliberately targeted at Kandyland’s type of nude dancing (to the exclusion of plays like Equus), in terms of both its applicable scope and the city’s enforcement.
* * * ifs * *
Nor could it be contended that selective applicability by stipulated enforcement should be treated differently from selective applicability by statutory text. See Barnes, 501 *511U.S. at 574[, 111 S.Ct. at 2464-65] (Scalia, J., concurring in judgment) (selective enforcement may affect a law’s generality). Were it otherwise, constitutional prohibitions could be circumvented with impunity.
Id. at 328 n. 12, 120 S.Ct. at 1412 n. 12 (Stevens, J., dissenting). The plurality in Erie rejected this argument and acknowledged that its own analysis presupposed that the public nudity ban had “the effect of limiting one particular means of expressing the kind of erotic message being disseminated at Kandyland.” Id. at 293, 120 S.Ct. at 1393.
The same is true of the public nudity ban in Barnes. Notwithstanding the absence of any express exemption, the public nudity ban there had been construed by the state courts to exclude theatrical nudity.9 The Supreme Court acknowledged this limiting construction on the ordinance as a legitimate effort by the state courts to “save it from a facial overbreadth attack.” Barnes, 501 U.S. at 564 n. 1, 111 S.Ct. at 2459 n. 1. In his concurring opinion, Justice Scalia agreed:
Respondents also contend that the statute, as interpreted, is not content-neutral in the expressive conduct to which it applies, since it allegedly does not apply to nudity in theatrical productions. See State v. Baysinger, 272 Ind. 236, 247, 397 N.E.2d 580, 587 (1979). I am not sure that theater versus non-theater represents a distinction based on content, rather than format, but assuming that it does, the argument nonetheless fails for the reason the plurality describes, ante, at 564, n. 1, 111 S.Ct. at 2459 n. 1.
Id. at 574 n. 2, 111 S.Ct. at 2464 n. 2.
By including an express exemption for theatrical nudity, Henrico merely put in writing what was implicit in both the *512Erie and Barnes public nudity bans. The exemption in the Henrico ordinance does nothing more than ensure that the ordinance incidentally restricts the least amount of expressive conduct, and thus, protects the ordinance against an over-breadth challenge. See, e.g., Giovani Carandola, Ltd. v. Bason, 303 F.3d 507, 517-19 (4th Cir.2002) (holding lack of a theater exemption raised overbreadth problems sufficient to warrant a preliminary injunction).
In addition, the theatrical nudity exemption reflects a legitimate recognition of the unique secondary effects associated with erotic clubs. “Establishments that purvey erotica, live or pictorial, tend to be tawdry, to be offensive to many people, and to attract a dubious, sometimes a disorderly, clientele.” Blue Canary Corp. v. City of Milwaukee, 251 F.3d 1121, 1124 (7th Cir.2001). The impact of erotic dancing and other sexually oriented businesses on the surrounding community is “all too real.” Alameda Books, Inc., 535 U.S. at 444, 122 S.Ct. at 1739 (Kennedy, J., concurring).10
A public nudity ban should be “properly evaluated as a content-neutral restriction because the interest in combating the secondary effects associated with those clubs is unrelated to the suppression of the erotic message conveyed by nude dancing.” Erie, 529 U.S. at 296, 120 S.Ct. at 1394; see also Clark v. City of Lakewood, 259 F.3d 996, 1004 (9th Cir.2001). So, while the messages conveyed by erotic dancing and theatrical nudity may be similar, the social by-products of each medium may be considerably different. See DLS, Inc. v. Chattanooga, 107 F.3d 403, 412 n. 9 (6th Cir.1997).11 Within *513the “limited field of regulations on public exhibitions of adult entertainment,” therefore, the presence of negative secondary effects permits public nudity regulations to be treated “as content-neutral and so subject only to intermediate scrutiny.” Giovani Carandola, Ltd., 303 F.3d at 515.
All of this leads to the application of the four-part test governing content-neutral restrictions on speech. Under that test, the Henrico ordinance survives scrutiny if it (i) falls within “the constitutional power” of the county, (ii) furthers an “important or substantial government interest,” (iii) furthers that interest in a manner “unrelated to the suppression of free expression,” and (iv) imposes no greater incidental restriction on protected speech “than is essential to the furtherance of that interest.” Erie, 529 U.S. at 296-301, 120 S.Ct. at 1394-97; see also Barnes, 501 U.S. at 567, 111 S.Ct. at 2461 (quoting United States v. O'Brien, 391 U.S. 367, 376-77, 88 S.Ct. 1673, 1678-79, 20 L.Ed.2d 672 (1968)). Appellants concede the Henrico public nudity ban satisfies prong one. They make no mention of prong two, except to mischaracterize it as requiring a “compelling” state interest, a requirement reserved only for content-based restrictions. Appellants focus their challenge on prongs three and four.
On the third prong, appellants argue that the purpose of the ordinance is unrelated to the suppression of free expression, but its application is not. In support, appellants again assert that the theatrical exemption (written into the text of the ordinance) requires law enforcement officials to make content-based distinctions. As noted earlier, however, the same exemption was present in Barnes and Erie. It serves an important limiting function and thereby avoids potential overbreadth problems with the ordinance. See Barnes, 501 U.S. at 564 n. 1, 111 S.Ct. at 2459 n. 1. The exemption also *514rests on a valid assessment of the differing secondary effects between the two venues. The focus on secondary effects was at the heart of the Erie holding:
Even if we had not already rejected the view that a ban on public nudity is necessarily related to the suppression of the erotic message of nude dancing, we would do so now because the premise of such a view is flawed. The State’s interest in preventing harmful secondary effects is not related to the suppression of expression.
Erie, 529 U.S. at 293, 120 S.Ct. at 1393. The theatrical exemption, therefore, does not violate the third prong of the content-neutral test any more than it did in Barnes or Erie.
Appellants also contend that the Henrico ordinance violates the fourth prong. On this issue, appellants claim that the legislative intent of the ordinance was merely “to prevent urinating in public and similar problems.” But, because the literal text of the ordinance also applies to erotic dancing, appellants reason, the ordinance goes further than necessary “to prevent or deter public urination, ‘mooning’ or skinny dipping.”
We cannot accept this analysis for several reasons. To begin with, the trial court made no factual finding that the purpose of the ordinance was limited to public urination, mooning, and skinny dipping. Appellants’ assertion appears to be taken from a memo from a lieutenant in the county police department to the police chief. The memo mentions the need for an ordinance to outlaw public urination, mooning, and skinny dipping. The same memo, however, also adds that the ordinance should prohibit “generally being nude in public.” Appellants’ assertion, therefore, relies on a non-legislative source that, in any event, contemplates a greater scope than merely proscribing mooning, public urination, and skinny dipping.
The only reliable source for legislative intent in this record can be found in a memo of the Henrico County Board of Supervisors accompanying the proposed ordinance at the time of its enactment. It makes clear that the stated purpose of *515the public nudity ban involves broad concerns over “public morality” and the need to regulate conduct that the legislative body deemed “injurious to the health, safety and general welfare” of the community. It was exactly these concerns over “secondary effects, such as the impacts on public health, safety, and welfare,” Erie explained, “which we have previously recognized are ‘caused by the presence of even one such’ establishment.” Erie, 529 U.S. at 291, 120 S.Ct. at 1392 (citation omitted). Barnes likewise found that an identical expression of the “traditional police power” of a state to “provide for the public health, safety, and morals” may serve as a permissible legislative goal for the enactment of a public nudity ordinance applicable to erotic dancing. Barnes, 501 U.S. at 569, 111 S.Ct. at 2462.12
Properly applied, the fourth prong of the Erie content-neutral test requires us to consider whether the ordinance imposes too great an incidental burden on speech. Before engaging in this analysis, we must first frame the issue precisely. The only constitutional right here (albeit one “marginally” within the “outer perimeters” of the First Amendment, Barnes, 501 U.S. at 566, 111 S.Ct. at 2460) is the erotic message implicit in nude or semi-nude dancing. There is no general right to take one’s clothes off in public. Nor is there a constitutional right to wear pasties and G-strings rather than the lingerie-like tops and bottoms required by the Henrico *516ordinance. Thus, we cannot ask whether requiring slightly more clothes restricts the erotic dancer’s right to be less clothed. “Being ‘in a state of nudity,’ ” after all, “is not an inherently expressive condition.” Erie, 529 U.S. at 289, 120 S.Ct. at 1391. Instead, we must ask whether the ordinance unduly burdens the dancer’s ability to express her erotic message by requiring her to cover up slightly more of her body with slightly more fabric.
Erie held that going from complete nudity to being partly clothed (with pasties and a G-string) involved a de minimis impact on the ability of a dancer to express eroticism. Erie, 529 U.S. at 294, 120 S.Ct. at 1393-94. The Henrico ordinance, in contrast, does not involve a transition from totally nude to partly clothed, but rather one from partly clothed to slightly more partly clothed. If going from naked to non-naked involves a constitutionally insignificant difference in degree, then the incrementally more fabric required by the Henrico ordinance can hardly constitute a constitutionally fatal difference. In this respect, the Henrico ordinance involves no more of a burden on the dancer’s free speech than the Erie requirement to wear some form of clothing in the first place. The dancer’s erotic message still reaches its intended audience. The additional clothing just “makes the message slightly less graphic.” Barnes, 501 U.S. at 571, 111 S.Ct. at 2463.
In other words, the pasties and G-string requirement should be understood as the “bare minimum necessary to achieve the state’s purpose.” Barnes, 501 U.S. at 572, 111 S.Ct. at 2463. It necessarily follows that this requirement does not represent “the maximum requirements of dress that an anti-nudity ordinance may impose.” Café 207 v. St. Johns County, 856 F.Supp. 641, 645-46 (M.D.Fla.1994), aff'd, 66 F.3d 272 (11th Cir.1995); see also Bright Lights v. City of Newport, 830 F.Supp. 378, 383-84 (E.D.Ky.1993). Thus, by going slightly beyond the pasties and G-string requirement, the Henrico public nudity ordinance did not so prejudice the eroticism inherent in the dancer’s expressive conduct as to run afoul of the First Amendment.
*517Moreover, in determining whether “particular conduct possesses sufficient communicative elements to bring the First Amendment into play,” we should consider not only the messenger’s intent but also whether “the likelihood was great that the message would be understood by those who viewed it.” Texas v. Johnson, 491 U.S. 397, 404, 109 S.Ct. 2533, 2539, 105 L.Ed.2d 342 (1989) (quoting Spence v. Washington, 418 U.S. 405, 410-11, 94 S.Ct. 2727, 2730, 41 L.Ed.2d 842 (1974)). Along these same lines, we do not accept appellants’ unstated assumption that the more graphic the dancer’s display of nudity the more erotic her message necessarily becomes. While that may be true at the extremes (like the contrast between a dancer in a snow skiing suit and one completely naked), it is not true at the margins (like the contrast between a dancer wearing almost nothing and one wearing slightly more than almost nothing).
B. The Ordinance Is Not Void For Vagueness.
An enactment may be found void for vagueness under either of two related theories. See Hill v. Colorado, 530 U.S. 703, 732, 120 S.Ct. 2480, 2498, 147 L.Ed.2d 597 (2000). First, if a statute “fails to provide people of ordinary intelligence a reasonable opportunity to understand what conduct it prohibits” it may be found vague. Id. Second, an enactment may be found vague if “it authorizes or even encourages arbitrary and discriminatory enforcement.” Id.
Appellants assert both vagueness infirmities with Henrico’s public nudity ordinance. On the first point, appellants contend that Henrico officials never gave appellants any advance warning that their conduct violated the public nudity ordinance. County officials, however, did not have to give the erotic club or any of its dancers specific notice of the ordinance. The mere promulgation of the ordinance was notice to all. See generally Bryan v. United States, 524 U.S. 184, 196, 118 S.Ct. 1939, 1947-48, 141 L.Ed.2d 197 (1998) (recognizing the “traditional rule that ignorance of the law is no excuse”). “The determination whether a criminal statute provides fair warning of its prohibitions must be made on the basis of the *518statute itself and the other pertinent law, rather than on the basis of an ad hoc appraisal of the subjective expectations of particular defendants.” Bouie v. Columbia, 378 U.S. 347, 355 n. 5, 84 S.Ct. 1697, 1703 n. 5, 12 L.Ed.2d 894 (1964). Under settled law, therefore, we must apply “an objective test for determining whether a statute is vague.” Laurence H. Tribe, Constitutional Law § 12-31, at 1033 n. 3 (2d ed. 1988).
The proper test focuses on whether a reasonable person could have understood what the Henrico public nudity ordinance literally proscribed. See Hill, 530 U.S. at 733, 120 S.Ct. at 2498. The Virginia Supreme Court resolved that issue in Wayside Rest., Inc. v. Virginia Beach, 215 Va. 231, 236, 208 S.E.2d 51, 55 (1974). There, an erotic club challenged a similar public nudity ordinance on vagueness grounds. The Virginia Supreme Court held that the challenged terms in the ordinance were “in common use” and “readily understood by the average person.” Id. The Henrico ordinance uses nearly identical language, having been patterned (the evidence at trial proved) expressly after the Virginia Beach ordinance approved by Wayside Rest., Inc.
For example, the Henrico ordinance defines a “state of nudity” in a manner similar to the public nudity ordinance in Wayside Rest., Inc., 215 Va. at 232 n. 1, 208 S.E.2d at 52 n. 1. The words used in the definition section of the public nudity ordinance — “buttocks,” “female breast,” “top of the nipple” and the like — are commonly understood terms. Cf. Code § 18.2-390(2) (using identical language to define nudity). Similarly, the theater exemption in the Henrico ordinance tracks verbatim the exemption in Wayside Rest., Inc., 215 Va. at 232 n. 1, 208 S.E.2d at 52 n. 1. Indeed, the Virginia Supreme Court found that the most arguably ambiguous language in the exemption — the catch-all phrase “other similar establishment” following the list of artistic venues like plays, dramas, and theaters — was not unconstitutionally vague. Id. at 236, 208 S.E.2d at 55; see also Bomhower v. Virginia Beach, 76 F.Supp.2d 681, 686 (E.D.Va.1999) (rejecting similar vagueness challenge to a public nudity ordinance).
*519In addition, a specific “scienter requirement” in an ordinance (requiring that criminal culpability be grounded on knowing violations of law) further protects a law from a vagueness challenge. Hill, 530 U.S. at 732, 120 S.Ct. at 2498. A scienter requirement “may mitigate a law’s vagueness, especially with respect to the adequacy of notice to the complainant that his conduct is proscribed.” Hoffman Estates v. Flipside, Hoffman Estates, Inc., 455 U.S. 489, 499,102 S.Ct. 1186, 1193, 71 L.Ed.2d 362 (1982). The Henrico ordinance contains a specific scienter requirement that the accused must “knowingly, voluntarily and intentionally” be in public in a “state of nudity.” Henrico County Code § 13-107(b). This scienter requirement, built into the text of the ordinance, further undermines appellants’ claim of inadequate notice.
We also disagree with appellants’ argument that the vagueness test should turn on whether the Henrico ordinance applies to “technical” violators like women wearing “contemporary swimwear” or “short-shorts,” or mothers engaged in breast feeding. As the United States Supreme Court recently emphasized, “speculation about possible vagueness in hypothetical situations not before the Court” should be given no weight in the analysis. Hill, 530 U.S. at 733, 120 S.Ct. at 2498 (citing United States v. Raines, 362 U.S. 17, 23, 80 S.Ct. 519, 523-24, 4 L.Ed.2d 524 (1960)). “There is little doubt that imagination can conjure up hypothetical cases in which the meaning of these terms will be in nice question,” id. (quoting Am. Communications Ass’n. v. Douds, 339 U.S. 382, 412, 70 S.Ct. 674, 691, 94 L.Ed. 925 (1950)), but the focus must remain on the facts before the court.
As a result, one “who engages in some conduct that is clearly proscribed cannot complain of the vagueness of the law as applied to the conduct of others.” Hoffman Estates, 455 U.S. at 495, 102 S.Ct. at 1191; see also Parker v. Levy, 417 U.S. 733, 756, 94 S.Ct. 2547, 2561-62, 41 L.Ed.2d 439 (1974) (“One to whose conduct a statute clearly applies may not successfully challenge it for vagueness.”); Bomhower, 76 F.Supp.2d at 686 (holding that an erotic club, against which *520the public nudity ordinance clearly applied, could not assert vagueness claim on behalf of others). The erotic dancers in this case stripped down to pasties and G-strings. They were not wearing “contemporary swimwear” or “short-shorts.” Nor were they breast feeding on stage. Because the very “nature of judicial review constrains us to consider the case that is actually before us,” McConnell v. FEC, 540 U.S. —, 124 S.Ct. 619, 688, 157 L.Ed.2d 491, 2003 U.S. Lexis 9195, at *179 (2003) (citation omitted), we decline appellants’ invitation to offer an advisory opinion on such “hypothetical situations,” Hill, 530 U.S. at 733, 120 S.Ct. at 2498 (citation omitted).
We likewise disagree that the ordinance violated the vagueness test on the ground that “it authorizes or even encourages arbitrary and discriminatory enforcement.” Hill, 530 U.S. at 732, 120 S.Ct. at 2498. Because law enforcement always “requires the exercise of some decree of police judgment,” Grayned v. City of Rockford, 408 U.S. 104, 114, 92 S.Ct. 2294, 2302, 33 L.Ed.2d 222 (1972), a law should not be invalidated unless its clarity has been “designedly avoided so as to allow the net to be cast at large,” Papachristou v. City of Jacksonville, 405 U.S. 156, 166, 92 S.Ct. 839, 845, 31 L.Ed.2d 110 (1972) (citation omitted).
On this issue, we see no persuasive point to be made over the fact that a police officer must see a particular item of clothing to determine whether to issue a summons. It is entirely appropriate for an officer to examine the conduct in question and make a judgment as to whether, under the probable cause standard, the conduct is illegal.13 The vague*521ness test does not forbid individualized assessments by law enforcement officers. What it forbids is a law that, by its expansive sweep of language, enacts an elastic definition of illegality — one that authorizes an officer to define for himself what is and is not legal. Nothing in the Henrico ordinance goes that far.
C. The County Did Not Engage In Unlawful Selective Prosecution.
Even if the public nudity ordinance survives the vagueness test, appellants argue, the County still violated equal protection principles by singling them out for selective prosecution. This assertion rests primarily on the prosecutor’s concession that he would not prosecute “technical” violations of the ordinance which would include some forms of skimpy swimwear at public pools, nursing mothers in public, and the like. We reject this claim for three reasons.
First, the structure of tripartite government creates a judicial presumption in favor of “broad” prosecutorial discretion. See United States v. Armstrong, 517 U.S. 456, 464-65, 116 S.Ct. 1480, 1486-87, 134 L.Ed.2d 687 (1996). “This broad discretion rests largely on the recognition that the decision to prosecute is particularly ill-suited to judicial review.” Wayte v. United States, 470 U.S. 598, 607, 105 S.Ct. 1524, 1530, 84 L.Ed.2d 547 (1985). “Even in the criminal-law field, a selective prosecution claim is a rara avis.” Reno v. Am.-Arab Anti-Discrimination Comm., 525 U.S. 471, 489, 119 S.Ct. 936, 946, 142 L.Ed.2d 940 (1999). Thus, “[i]n the ordinary case, ‘so long as the prosecutor has probable cause to believe that the accused committed an offense defined by statute, the decision whether or not to prosecute ... generally rests entirely in his discretion.’ ” Armstrong, 517 U.S. at 464, 116 S.Ct. at 1486 (quoting Bordenkircher v. Hayes, 434 U.S. 357, 364, 98 S.Ct. 663, 668, 54 L.Ed.2d 604 (1978)).
*522“To succeed on a selective-prosecution claim, a defendant must demonstrate that the prosecutor’s decision ‘was based on an unconstitutional motive.’” Rowsey v. Lee, 327 F.3d 335, 343 (4th Cir.2003) (citation omitted). In other words, a selective prosecution claim requires a showing that “the prosecutor has brought the charge for reasons forbidden by the Constitution.” Armstrong, 517 U.S. at 463,116 S.Ct. at 1486. The claim cannot succeed without proof that the prosecution was “ ‘deliberately based upon an unjustifiable standard such as race, religion, or other arbitrary classification,’ including the exercise of protected statutory and constitutional rights.” Wayte, 470 U.S. at 608, 105 S.Ct. at 1531 (quoting Bordenkircher, 434 U.S. at 364, 98 S.Ct. at 668; Oyler v. Boles, 368 U.S. 448, 456, 82 S.Ct. 501, 506, 7 L.Ed.2d 446 (1962), and citing United States v. Goodwin, 457 U.S. 368, 372, 102 S.Ct. 2485, 2488, 73 L.Ed.2d 74 (1982)) (citations omitted).
Appellants’ as-applied selective prosecution claim fails for the same reason their content-based attack fails: The dancers have no First Amendment right to wear pasties and G-strings rather than the lingerie-like tops and bottoms required by the Henrico ordinance. Because the ordinance involves a content-neutral regulation of conduct that does not unduly burden any protected erotic speech, appellants cannot claim they were being targeted for constitutionally suspect reasons. Put another way, appellants cannot show that Henri-co prosecuted them “because of’ their expression of constitutionally protected speech. Wayte, 470 U.S. at 610, 105 S.Ct. at 1532 (emphasis in original).
Second, the selective prosecution claim, having been rejected by the factfinder at trial, can only succeed on appeal if the facts demonstrate it as a matter.of law. The factual record cannot support this showing. No evidence proved any “technical violations” had in fact occurred in Henrico County. Appellants’ argument on this point, as well as the prosecutor’s remarks about it, involve purely hypothetical situations — the most fanciful being the observation that the enforcement of the public nudity ban would “permit Jennifer Lopez to wear one famously revealing dress,” but might prohibit her from *523wearing others. See post, at 536, 592 S.E.2d at 788 (quoting the federal court’s abstention order). Once one gets beyond the hypotheticals, no evidence in this case demonstrated that the prosecutors had used the ordinance to target erotic dancing. Just the opposite was shown: Thirty-eight individuals had been prosecuted under the public nudity ban, and this one case involves the only application of the ordinance against erotic dancers.
Finally, even if the hypothetical “technical cases” were real, the secondary effects doctrine provides a constitutionally adequate basis for judicial deference to prosecutorial discretion where no underlying constitutional infringement exists. See generally Erie, 529 U.S. at 295, 120 S.Ct. at 1394 (recognizing “that one specific occurrence of public nudity— nude erotic dancing — is particularly problematic because it produces harmful secondary effects”). The impact on the local community of a strip club featuring erotic dancers can hardly be equated with nursing mothers in public restaurants, swimmers at a neighborhood pool, or, for that matter, a surprise visit from a scantily-clad Jennifer Lopez. For the same reason the secondary effects principle provides legitimacy to the governmental interest in regulating the business of erotica, it also explains why prosecutors may make commonsense distinctions between nursing mothers and swimmers, on the one hand, and erotic dancers, flashers, and public urinators, on the other.14
D. The County Had Authority To Enact A Public Nudity Ordinance.
Appellants next claim that the Henrico public nudity ordinance exceeds the County’s local governmental powers. *524We disagree and hold that the ordinance involves a legitimate exercise of delegable state police powers.
Under Code § 15.2-1200, a county may “adopt such measures as it deems expedient to secure and promote the health, safety and general welfare of its inhabitants which are not inconsistent with the general laws of the Commonwealth.” 15 This delegation of police powers includes the power to regulate nude and semi-nude dancing. See Wayside Rest., Inc., 215 Va. at 283, 208 S.E.2d at 53 (finding power implicit in county’s power to prohibit “conduct which the local governing body reasonably deems to be contrary to the morals, health, safety and general welfare of the community”); see, e.g., Erie, 529 U.S. at 296, 120 S.Ct. at 1395 (“Erie’s efforts to protect public health and safety are clearly within the city’s police powers.”); Barnes, 501 U.S. at 569, 111 S.Ct. at 2462 (recognizing that “the traditional police powers of the States,” defined as “the authority to provide for the public health, safety, and morals,” provides a legitimate basis for public indecency statutes).
We also reject appellants’ assertion that the Henrico public nudity ordinance, while an otherwise valid expression of the general police power, should be invalidated because it goes further than state laws proscribing obscenity and indecent exposure. See Code §§ 18.2-375, 18.2-387. “The mere fact that the state, in the exercise of the police power, has made certain regulations, does not prohibit a municipality from exacting additional requirements.” Wayside Rest., Inc., 215 Va. at 234, 208 S.E.2d at 53 (quoting King v. Arlington County, 195 Va. 1084, 1090, 81 S.E.2d 587, 591 (1954)). This remains true as long as the locality “does not attempt to authorize by the ordinance what the legislature has forbidden *525or forbid what the legislature has expressly licensed, authorized, or required.” Id. at 234, 208 S.E.2d at 54.
E. The Evidence Supports The Trial Court’s Findings Of Fact.
Finally, appellants argue the trial court plainly erred in finding that their semi-nude dancing did not fall within the ordinance’s exemption for the performance of any “play, ballet, drama, tableau, production or motion picture in any theater, concert hall, museum of fine arts, school, institution of higher learning or other similar establishment which is primarily devoted to such exhibitions, presentations, shows or performances as a form of expression of opinion, communication, speech, ideas, information, art or drama.” Henrico County Code § 13 — 107(c). The trial court found as a fact that Gold City was not a “theater,” and the dancers were not engaged in any “theatrical performance either.” These conclusions, appellants contend, fail to take into account their unique “moves using the pole mounted on the bar,” the “special costumes” worn (albeit briefly) during the dance, as well as the overall context of their dancing.
The trial judge’s factual findings cannot be disturbed on appeal unless no “rational trier of fact” could have come to the conclusions he did. Kelly v. Commonwealth, 41 Va.App. 250, 257, 584 S.E.2d 444, 447 (2003) (en banc) (quoting Jackson v. Virginia, 443 U.S. 307, 319, 99 S.Ct. 2781, 2789, 61 L.Ed.2d 560 (1979)); Holmes v. Commonwealth, 41 Va.App. 690, 691, 589 S.E.2d 11, 11 (2003); Crowder v. Commonwealth, 41 Va.App. 658, 663, 588 S.E.2d 384, 387 (2003). That cannot be said here. The dancers took their clothes off on the bar, not a theatrical stage. They did not use scripts, read lines, or sing. No one passed out playbills or programs. No stage hands set up props or made scene changes. No evidence suggests that the audience came to see a “play, ballet, drama, tableau, production or motion picture” or showed up at Gold City thinking it was a “theater” or similar establishment under Henrico County Code § 13-107(c). The trial court, therefore, *526was not plainly wrong in finding the theatrical exemption inapplicable.
III.
Finding no error in either the trial court’s legal reasoning or the rationality of its factfinding, we affirm.
Affirmed.
. Virtually identical ordinances include Accomack County Code § 58-2; City of Alexandria Code § 13-1-17; Town of Ashland Code § 12-8.9; Blacksburg City Code § 14-108; Chesterfield County Code § 14-33; City of Fairfax Code § 54-227; City of Falls Church Code § 22-40; City of Franklin Code § 19-33; County of Franklin Code § 13-13; Town of Leesburg Code § 11-91; City of Manassas Code § 78-261; Montgomery County Code § 7-38; City of Newport News Code § 27-10.2; City of Norfolk Code § 28-12; City of Radford Code § 60-2; City of Roanoke Code § 21-125; City of Richmond Code § 20-104; County of Southampton Code § 10-40; City of Suffolk Code § 54-34; City of Virginia Beach Code § 22-10; York County Code § 15.5-10.1. Ordinances recognizing similar offenses include City of Emporia Code § 90-53; City of Fredericksburg Code § 13-16.1; City of Hopewell Code § 24 — 10 (indecent exposure); Town of Mount Jackson Code § 38-30 (indecent exposure); New Kent County Code § 46-15 (indecent exposure); City of Norton Code § 14-219 (indecent exposure); City of Petersburg Code § 74-315 (indecent exposure); Town of Purcellville Code § 46-79 (indecent exposure); City of Salem Code § 58-17 (indecent exposure); City of Smithfield Code § 50-14 (indecent exposure); Town of South Boston Code § 70-123 (indecent exposure); Spotsylvania County Code § 14-17 ("Indecent Exposure By Entertainers, Waitresses, Waiters, etc.”); Stafford County Code § 17-9 (indecent exposure); Town of Warrenton Code § 11-16 (indecent exposure); City of Winchester Code § 15-9 (indecent exposure); City of Wytheville Code § 9-14 (indecent exposure).
. The Virginia Supreme Court rejected a challenge to the Virginia Beach public nudity ordinance in Wayside Rest., Inc. v. Virginia Beach, 215 Va. 231, 208 S.E.2d 51 (1974).
. At the time of the offenses in this case, Henrico County Code § 13— 107 made it a misdemeanor to
expose the human male or female genitals, pubic area or buttocks or to cover any of them with less than a fully opaque covering, or the showing of the female breast or any portion thereof below the top of the nipple, or covering of the breast or any portion thereof below the top of the nipple with less than a fully opaque covering.
Henrico County Code § 13-107(a).
. In their appellate brief, appellants quote statements of the County's counsel made during the federal district court hearing. See J.A. 131-35, 141-71. None of these statements, however, appears in the trial record of the case before us. Under basic principles of appellate review, we may not go beyond the record developed in the trial court. See John v. Im, 263 Va. 315, 320, 559 S.E.2d 694, 697 (2002) (On appeal, “we are limited to an examination of the record before us” and cannot consider evidence that the appellant "failed to submit to the trial court.”). The transcript of the federal district court proceeding, therefore, should not have been included in the joint appendix. See Albert v. Albert, 38 Va.App. 284, 291 n. 2, 563 S.E.2d 389, 392 n. 2 (2002) (“While the appendix contains worksheets, they were not offered into evidence at the hearing nor were they made part of the proffer. These documents, therefore, are not part of the record and will not be considered by this Court.”).
. The full text of the exemption provides:
Nothing contained in this section shall be construed to apply to the exhibition, presentation, showing or performance of any play, ballet, drama, tableau, production or motion picture in any theater, concert hall, museum of fine arts, school, institution of higher learning or other similar establishment which is primarily devoted to such exhibitions, presentations, shows or performances as a form of expression of opinion, communication, speech, ideas, information, art or drama.
*506Henrico County Code § 13-107(c).
. Sprinkled throughout appellants’ brief are isolated sentences, sometimes mere phrases or words, that implicate other legal issues. In a single sentence, for example, appellants claim the ordinance "operates as a regulatory taking without just compensation” in violation of due process principles. Appellants also mention, in an argument heading, the right of "free association" without any further elaboration. The word "over-breadth” is used once, apparently (and erroneously) as a synonym for the word "vagueness.” Similar perfunctory statements are made about the lack of "prompt judicial review” and the County's failure to leave "sufficient sites for adult businesses to open and operate.” The trial record reflects that few, if any, of these conclusory assertions were adequately raised below. In any event, we will not consider them on appeal. Rule 5A:20(e) requires the appellants’ brief to include, among other things, the "principles of law, the argument, and the authorities relating to each question presented.” Statements unsupported by "argument, authority, or citations to the record” do not merit appellate consideration. Thomas v. Commonwealth, 38 Va.App. 319, 321 n. 1, 563 S.E.2d 406, 407 n. 1 (2002); Dickerson v. Commonwealth, 36 Va.App. 8, 15, 548 S.E.2d 230, 234 (2001); Bennett v. Commonwealth, 35 Va.App. 442, 452, 546 S.E.2d 209, 213 (2001); Buchanan v. Buchanan, 14 Va.App. 53, 56, 415 S.E.2d 237, 239 (1992).
. See also United States v. Biocic, 928 F.2d 112, 116 (4th Cir.1991) (finding no right to public nudity under "the profound rights of person-hood and privacy”); Chapin v. Southampton, 457 F.Supp. 1170, 1174 (E.D.N.Y.1978) (“It is undoubted that public nudity can be banned.” (citation omitted)); Tri-State Metro Naturists v. Lower, 219 N.J.Super. 103, 529 A.2d 1047, 1050-53 (Law Div.1987) (recognizing that no right to appear nude in public exists under the First, Fifth, or Fourteenth Amendments); People v. Hollman, 68 N.Y.2d 202, 507 N.Y.S.2d 977, 500 N.E.2d 297, 301 (1986) (observing that "prohibiting public nudity is plainly within the State’s police powers”); State v. Ciancanelli, 181 Or.App. 1, 45 P.3d 451, 455 (2002) (surveying historical disdain toward public nudity); Lacour v. State, 21 S.W.3d 794, 796 (Tex.App.2000) *508(recognizing public nudity as "merely conduct; not expressive conduct”).
. Laws that "by their terms distinguish favored speech from disfavored speech on the basis of the ideas or views expressed are content based.” Bartnicki v. Vopper, 532 U.S. 514, 526, 121 S.Ct. 1753, 1760, 149 L.Ed.2d 787 (2001) (quoting Turner Broad. System, Inc. v. FCC, 512 U.S. 622, 642-43, 114 S.Ct. 2445, 2459, 129 L.Ed.2d 497 (1994)). Content-based regulations on speech can withstand a constitutional challenge only by satisfying "the most exacting scrutiny.” Turner Broad. System, Inc., 512 U.S. at 641-42, 114 S.Ct. at 2458-59; see also Republican Party of Minnesota v. White, 536 U.S. 765, 774-75, 122 S.Ct. 2528, 2534-35, 153 L.Ed.2d 694 (2002); Los Angeles v. Alameda Books, Inc., 535 U.S. 425, 434, 122 S.Ct. 1728, 1733-34, 152 L.Ed.2d 670 (2002) (plurality).
. See Indiana v. Baysinger, 272 Ind. 236, 397 N.E.2d 580, 587 (1979) (noting that it is “constitutionally required to tolerate or to allow some nudity as a part of some larger form of expression meriting protection” and, therefore, limiting the reach of the Indiana Public Indecency statute only to activities involving pure conduct containing no constitutionally protected expressive element); Glen Theatre, Inc. v. Pearson, 802 F.2d 287, 289 (7th Cir.1986) (basing its rejection of the plaintiff's overbreadth claim on the limiting construction provided by Baysinger).
. See Erie, 529 U.S. at 299, 120 S.Ct. at 1396 (rejecting suggestion in dissenting opinion that municipality must develop "specific evidentiary record” on secondary effects); Giovani Carandola, Ltd., 303 F.3d at 514 ("No record evidence supports this [secondary effects] claim.... Even though the Commission has submitted no direct evidence of legislative motive, we believe that precedent requires us to evaluate the challenged restrictions as content-neutral provisions aimed at secondary effects.”).
. A municipality's means for attacking secondary effects need not "greatly reduce these secondary effects.” SOB, Inc. v. County of Benton, 317 F.3d 856, 863 (8th Cir.2003) (citing Erie, 529 U.S. at 301, *513120 S.Ct. at 1397). Instead, the means must merely “further the interest in combating such effects.” Id. (citing Erie, 529 U.S. at 301, 120 S.Ct. at 1397). Municipalities enjoy this leeway to have “a reasonable opportunity to experiment with solutions to admittedly serious problems.” SOB, Inc., 317 F.3d at 863 (citation omitted).
. Even if we did not have this legislative history, the legislative intent underlying public nudity bans can be inferred as a matter of law. See Barnes, 501 U.S. at 567-68, 111 S.Ct. at 2461 ("It is impossible to discern, other than from the text of the statute, exactly what governmental interest the Indiana legislators had in mind when they enacted this statute.... Nonetheless, the statute’s purpose of protecting societal order and morality is clear from its text and history. Public indecency statutes of this sort are of ancient origin, and presently exist in at least 47 States. Public indecency, including nudity, was a criminal offense at common law, and this Court recognized the common law roots of the offense of 'gross and open indecency’ in Winters v. New York, 333 U.S. 507, 515, 68 S.Ct. 665, [670,] 92 L.Ed. 840 (1948). Public nudity was considered an act malum en se. Le Roy v. Sidley, 1 Sid. 168, 82 Eng. Rep. 1036 (K.B. 1664). Public indecency statutes such as the one before us reflect moral disapproval of people appearing in the nude among strangers in public places.”).
. Appellants claim the officers issued summonses to ten dancers on July 9, 2001, but arbitrarily allowed others to continue dancing. This disparity proves, appellants argue, the "unfettered discretion” given by the ordinance to law enforcement personnel. The truth is far less sinister, however. The Commonwealth’s Attorney had instructed each officer to charge only those dancers committing the offense "in the officer’s presence.” After observing the first ten dancers, the undercover officers had to leave the bar, pick up their summons books, and then fill out the paperwork for each of these dancers. During this timeframe other dancers evidently continued to dance. These dancers were not charged because they did not commit the offense in the officers' *521presence. As the sergeant in charge testified, "we charged everybody that we saw in violation.”
. Appellants also contend on brief that the County does not inspect "high-brow” venues such as "art museums or bállets” for potential violations of the public nudity ordinance. We find this assertion unpersuasive. Even if the theatrical exemption in the public nudity ordinance did not expressly justify this alleged policy of nonenforcement, see ante at 508 - 514, 592 S.E.2d at 775 - 777, no evidence in the record addresses (much less confirms) appellants' factual assertion.
. Under Dillon’s Rule, localities may exercise “only those powers which are expressly granted by the state legislature, those powers fairly or necessarily implied from expressly granted powers, and those powers which are essential and indispensable.” Arlington County v. White, 259 Va. 708, 712, 528 S.E.2d 706, 708 (2000) (quoting City of Virginia Beach v. Hay, 258 Va. 217, 221, 518 S.E.2d 314, 316 (1999) (citations omitted)).