¶ 1. Armin Nan-kin (Nankin) seeks review of a court of appeals' decision that upheld the constitutionality of Wis. Stat. § 74.37(6) (1997-98).1 This section operates to allow owners of property located in counties with a population of less than 500,000 to challenge a property assessment with a full trial in the circuit court; those ■with a population of 500,000 or more (populous counties) are not allowed a full trial "de novo" in the circuit court. Nankin contends that the statute is unconstitutional because it violates the constitutional guarantee of equal protection of the law, that is, it treats owners of property located in populous counties differently than owners of property located in other counties without a rational basis. We agree. We also conclude that § 74.37(6) is severable from the remainder of the statute. Accordingly, we reverse the determination made by the court of appeals and grant Nankin's motion for summary judgment.
FACTS AND PROCEDURAL HISTORY
¶ 2. The facts are undisputed. Nankin is trustee of a trust that owns a parcel of real property in the Village of Shorewood (Village) in Milwaukee County. On May 9,1998, Nankin filed a written objection to the village assessor's 1998 assessment of the property. On May 11, 1998, the Village of Shorewood Board of Review (Board) conducted a hearing on this objection. At the conclusion of the hearing, the Board voted to sustain the assessment of the village assessor.
¶ 3. Pursuant to statute, once a board of review renders its decision, appeal from the decision may be *94accomplished in one of three ways.2 First, an owner can appeal from the board's determination by an action for certiorari to the circuit court under Wis. Stat. § 70.47(13). Second, pursuant to Wis. Stat. § 70.85, a property owner may submit a written complaint with the department of revenue requesting that the department revalue the property. § 70.85(1), (4)(b). The department's decision may then be appealed through an action for certiorari in the county in which the property is located. § 70.85(4)(c). Third and finally, after paying the tax on the assessment, a property owner may proceed under Wis. Stat. § 74.37 with a claim for an excessive assessment against the taxation district3 or the county, depending on which entity collected the tax. § 74.37(1), (2)(a), (4)(b). Such claims seek "to recover that amount of general property tax imposed because the assessment of property was excessive." § 74.37(1). If this claim is denied, the aggrieved property owner may then commence an action in the circuit court to recover the amount of the claim not allowed. § 74.37(3)(d).
¶ 4. Because of Wis. Stat. § 74.37(6), however, Nankin was prohibited from pursuing this final option. This subsection provides that § 74.37 "does not apply in counties with a population of 500,000 or more." In this case, because the trust property was located in the Village of Shorewood in Milwaukee County, a county that had a population of 500,000 or more, Nankin could not file a claim under § 74.37.
*95¶ 5. On June 15,1998, Nankin filed a declaratory judgment action in the circuit court, seeking a declaration that Wis. Stat. § 74.37(6) was unconstitutional. In particular, he alleged that this statute violated (1) Article I, Section 1 of the Wisconsin Constitution and the Fourteenth Amendment of the United States Constitution, both of which guarantee equal protection under the law; (2) Article IV, Section 31(6) of the Wisconsin Constitution, which prohibits the enactment of special or private laws regarding the assessment or collection of taxes; and (3) Article VIII, Section 1 of the Wisconsin Constitution, which mandates that the rule of taxation shall be uniform. Nankin also sought a declaration from the court that § 74.37(6) was severable from the remainder of the statute; a permanent injunction prohibiting the defendant from asserting § 74.37(6) as a defense to any claim filed by Nankin regarding the 1998 assessment of property; and costs incurred, including reasonable attorney fees.
¶ 6. With respect to his equal protection claim, Nankin argued that the statute was unconstitutional because it legislated disparate treatment for persons who own property in municipalities in counties with a population of 500,000 or more and persons who own property in municipalities in other counties. Persons owning property in populous counties, Nankin argued, could ultimately only receive certiorari review of their property assessments in the circuit court, either under Wis. Stat. § 70.47(13) or Wis. Stat. § 70.85(4)(c). In contrast, persons owning property in other counties could receive de novo review in the circuit court by pursuing an action under Wis. Stat. § 74.37(3)(d). Nankin contended that there was no rational basis for this disparate treatment of property owners in assessment *96appeal options based solely on the population of the county in which the property is situated.
¶ 7. Nankin filed a motion for summary judgment. This motion included a claim that Wis. Stat. § 74.37(6) also violated Article IV, Section 18 of the Wisconsin Constitution. This constitutional provision limits the legislature from passing laws that have only limited application.
¶ 8. The Milwaukee County Circuit Court, the Honorable Diane S. Sykes, denied Nankin's motion and his request for declaratory relief, concluding that he failed to carry his burden of proving the statute unconstitutional beyond a reasonable doubt. With respect to Nankin's equal protection claim, the court determined that this question had been resolved in S.C. Johnson & Son, Inc. v. Town of Caledonia, 206 Wis. 2d 292, 557 N.W.2d 412 (Ct. App. 1996). The court followed this precedent and opined that it was reasonable for the legislature to exempt populous counties from this type of review based on the conclusion that de novo review of municipal board of review decisions in the circuit court would be unworkable in such counties. Certiorari review, the court noted, still provided a meaningful opportunity for judicial correction of municipal tax assessment errors, even though this review was far narrower than de novo review. The court also rejected Nankin's other constitutional claims and denied costs to Nankin.
¶ 9. The court of appeals, in a per curiam decision, affirmed the circuit court's decision. We accepted review to determine whether Wis. Stat. § 74.37(6) violated one or more of the following state constitutional provisions: (1) Article I, Section 1; (2) Article IV, Sec*97tion 31(6); or (3) Article IV, Section 18.4 Because we conclude that this statutory section violates Article I, Section 1, we will not review Nankin's other arguments. Our analysis also reveals that § 74.37(6) maybe severed from the remainder of the statute.
STANDARD OF REVIEW
¶ 10. A challenge to the constitutionality of a statute presents a question of law that we review under a de novo standard of review. Aicher v. Wis. Patients Comp. Fund, 2000 WI 98, ¶ 18, 237 Wis. 2d 99, 613 N.W.2d 849. We presume that the statute is constitutional and indulge "every presumption to sustain the law if at all possible_" Id. The burden is on the party challenging the statute to prove that the statute is unconstitutional beyond a reasonable doubt. Id. at ¶ 19. Any doubt must be resolved in favor of the constitutionality of the statute. Id. at ¶ 18.
EQUAL PROTECTION
¶ 11. Nankin challenges the constitutionality of Wis. Stat. § 74.37(6) on equal protection grounds.5 To *98prevail, he must show that the statute unconstitutionally treats members of similarly situated classes differently. Aicher, 2000 WI 98 at ¶ 56. In cases, like here, where the statutory classification does not involve a suspect class or a fundamental interest, we will sustain the classification if there exists any rational basis to support it. Milwaukee Brewers v. DHSS, 130 Wis. 2d 79, 98, 387 N.W.2d 254 (1986). A statute violates equal protection only when "the legislature has made an irrational or arbitrary classification, one that has no reasonable purpose or relationship to the facts or a proper state policy." Id. at 99. Any doubts must be resolved in favor of the reasonableness of the classification. State v. Hezzie R., 219 Wis. 2d 848, 894, 580 N.W.2d 660 (1998).
¶ 12. " 'The fact [that] a statutory classification results in some inequity. . .does not provide sufficient grounds for invalidating a legislative enactment.'" Id. at 893-94 (quoting State v. McManus, 152 Wis. 2d 113, 131, 447 N.W.2d 654 (1989)). Indeed, " '[e]qual protection does not deny a state the power to treat persons within its jurisdiction differently....'" Id. at 893 (quoting McManus, 152 Wis. 2d at 131). However, "[t]he basic test is not whether some inequality results from the classification but whether there exists a rational basis to justify the inequality of the classification." Milwaukee Brewers, 130 Wis. 2d at 99. In determining whether a rational basis exists, we look first to determine whether the legislature articulated a rationale for its determination. See id. at 99-101. If we cannot identify any such articulated rationale, it is the court's obligation to construct one. Id. at 101.
*99¶ 13. We conclude that Nankin has met his burden in proving beyond a reasonable doubt that Wis. Stat. § 74.37(6) violates equal protection. We reach this conclusion based on three separate determinations. The first determination is that, in enacting § 74.37(6), the legislature created a distinct classification of citizens, that is, owners of property located in counties with a population of 500,000 people or more. The parties do not dispute that the statute created this classification.
¶ 14. Our second determination is that the legislation treats this class significantly different from all others similarly situated. In particular, as Nankin asserts, the statute treats the class differently by prohibiting it from filing a circuit court action under Wis. Stat. § 74.37(3)(d) to challenge the excessiveness of their property assessment. All other owners of property located in counties with a population of less than 500,000 are entitled to proceed under this statute. The inequality results from advantages stemming from circuit court actions under § 74.37(3)(d), which are not available to the disfavored class. We provide analysis on our conclusion below.
¶ 15. Our final determination is that Nankin has met his burden in proving beyond a reasonable doubt that there is no rational basis for the classification under Wis. Stat. § 74.37(6). The legislature did not articulate any rationale for the classification, and we are unable to construct a rationale for this classification. There is no rational basis for the legislature to treat owners of property located in municipalities in different counties dissimilarly in challenging their property tax assessments based solely on the population of the county in which the property is situated. *100Again, our analysis below shows how we reach this determination.
¶ 16. We begin with some background on property tax administration for general property in Wisconsin. On the whole, municipalities form the primary units of property tax administration in Wisconsin. In particular, the statutes designate any town, city, or village in which general property taxes are levied and collected as taxation districts. Wis. Stat. § 70.045. Each taxation district is required to have an assessor, and this assessor may be appointed or elected. Wis. Stat. § 70.05(1).6 In the alternative and under certain conditions, counties may adopt and implement a county assessor system. Wis. Stat. § 70.99(1).
¶ 17. The assessment of general property in each town, city, and village is made according to Wis. Stat. Ch. 70. Wis. Stat. § 70.05(1). It is the assessor's duty to discover, list, and value all taxable real and personal property within the taxation district and annually report such information in an assessment roll for the district. Wis. Stat. §§ 70.10, 70.29, 70.32(l)-(2). If a property owner disagrees with an assessment, the owner may file a formal objection with the municipality's board of review. Wis. Stat. § 70.47(7)(a).7
¶ 18. The board of review, however, "is not an assessing body but rather a gwasi-judicial body whose duty it is to hear evidence tending to show errors in the *101assessment roll and to decide upon the evidence adduced whether the assessor's valuation is correct." State ex rel. I.B.M. Corp. v. Bd. of Review of Fond du Lac, 231 Wis. 303, 306, 285 N.W. 784 (1939). The board must presume that the assessor's valuation is correct, and this presumption may be rebutted only by sufficient showing upon sworn oral testimony by the objector that the valuation is incorrect. Wis. Stat. § 70.47(8)(i). If the board determines that the assessment is too high or too low, it must raise or lower the assessment accordingly. § 70.47(6), (9)(a).
¶ 19. After the board renders its decision, the property owner may pursue one of the three appeal options discussed above. Our analysis focuses on the differences between the certiorari review available under Wis. Stat. §§ 70.47(13) and 70.85(4)(c) and a circuit court action permitted under Wis. Stat. § 74.37(3)(d). A close analysis reveals that a property owner who is able to pursue a circuit court action is placed at a significant advantage when compared to other property owners.
¶ 20. Certiorari review under Wis. Stat. § 70.47(13)8 is limited to a review of the record made before the board of review. State ex rel. Hemker v. Hugged, 114 Wis. 2d 320, 323, 338 N.W.2d 335 (Ct. App. *1021983). Thus, the court may not conduct its own factual inquiry and may not admit any new evidence. Id. On review, the court only considers the following factors:
(1) whether the board acted within its jurisdiction;
(2) whether the board acted according to law;
(3) whether the board's action was arbitrary, oppressive or unreasonable, representing its will rather than its judgment; and (4) whether the evidence was such that the board might reasonably make the order or determination in question.
Waste Mgmt., Inc. v. Kenosha County Bd. of Review, 184 Wis. 2d 541, 554, 516 N.W.2d 695 (1994).
¶ 21. An assessment that was made in accordance with the statutory mandate must be upheld if it can be supported by any reasonable view of the evidence. Id. The court will not make an assessment of the property; instead, if it finds any error that renders the assessment void, the court must set aside the assessment and remand to the board for further proceedings. Id. at 566; State ex rel. Garton Toy Co. v. Town of Mosel, 32 Wis. 2d 253, 258, 145 N.W.2d 129 (1966); Wis. Stat. § 70.47(13).
¶ 22. We compare this review to a circuit court action permitted under Wis. Stat. § 74.37(3)(d). Again, pursuant to this section, after a claim in the taxation district or county is disallowed, a property owner may file an action in the circuit court to recover any amount of property tax imposed as a result of an excessive assessment. § 74.37(1), (2), (3)(d). This action proceeds according to state civil procedure and practice. See Wis. Stat. § 801.01(1), (2).
¶ 23. The Village argues that S.C. Johnson, 206 Wis. 2d 292, already concluded that the differences *103between certiorari review and a court action under Wis. Stat. § 74.37(3)(d) do not result in significantly different treatment between owners of property located in populous counties and other property owners in the state. In S.C. Johnson, an owner of property located in Racine County filed a claim and action under § 74.37. Id. at 296. After concluding that the owner could pursue this action, the court examined whether prohibiting this right in populous counties violated equal protection. Id. at 306-08. The court addressed this argument even though it concluded that the party raising the argument^, a municipality, had no standing to challenge the constitutionality of the statute. Id. at 302-04, 306-08. The court concluded that, despite the anomalies that existed between certiorari review and a § 74.37(3)(d) action, the legislative distinction was insufficient to violate equal protection. Id. at 308. In reaching its determination, the court noted that the distinction merely dealt with "the method by which the right of judicial review is pursued," rather than whether judicial review was provided at all, which the court suggested may have raised some equal protection concerns. Id.
¶ 24. We disagree with the characterization made by the court of appeals. The problem with this characterization is that an action under Wis. Stat. § 74.37(3)(d) is not simply another means of judicial review. Judicial review entails "[a] court's review of a lower court's or an administrative body's factual or legal findings." Black's Law Dictionary 852 (7th ed. 1999). That is not the case in an action under § 74.37(3)(d). Instead, this statute affords the claimant the right to pursue an action according to state civil *104practice and procedure, including the right to a trial.9 This difference is significant because, unlike certiorari review, § 74.37(3)(d) actions allow property owners to again fully contest their case in a court trial despite having contested it before the board of review.
¶ 25. The differences between such court actions and certiorari review are considerable. To begin with, as mentioned above, certiorari review is limited to a review of the record. In comparison, during a court action, if the action proceeds to trial, the court may make its determination without regard to any determination made at any earlier proceeding. Instead, new evidence may be introduced, and the court may examine this evidence in making its determination. In addition, unlike certiorari review, during a court trial, the court may make its determination without giving deference to any determination made at a previous proceeding. The court must only give presumptive weight to the assessor's assessment. Wis. Stat. § 70.49(2). Finally, unlike a certiorari review, in a trial, the court, upon making its determination, is not required to remand to the board for an assessment. It may make its determination based on the evidence. The court is only limited in the respect that, if a reassessment is necessary, the court must continue the action and *105order the reassessment before rendering its judgment. Wis. Stat. § 74.39(1). However, even if a reassessment is necessary, the court may still proceed to judgment if it is in the best interests of all parties to the action. § 74.39(3).
¶ 26. The legislative history of Wis. Stat. § 74.37 also supports the conclusion that the legislature intended an action for excessive assessment to provide a significantly different option for property owners than mere certiorari review in challenging their assessments. In 1953, the legislature created Wis. Stat. § 70.47(9a) (1953), which permitted certiorari review from the board of review decision, and Wis. Stat. § 74.73(4) (1953), which prohibited any claim or court action based upon an alleged excessive assessment and restricted appeal from the board of review to the manner prescribed under § 70.47(9a) (1953) and other statutes.10 See §§ 1-2, ch. 435, Laws of 1953. A drafting request dated January 25, 1955, shows that Lieutenant Governor Warren Knowles wanted to revise ch. 435, Laws of 1953 to allow the circuit court to "take testimony and make finding of fact in assessment cases." Drafting Request, microformed on ch. 440, Laws of 1955 (Leg. Ref. Bureau). More specifically, he sought to amend certiorari- review in the circuit court so that the court had "the authority to weigh evidence and make a final determination of the facts." Id. The request noted that, at that time, the court could only *106remand to the board of review for a new assessment. Id.
¶ 27. In response to this request, however, the legislature did not broaden the scope of certiorari review in the circuit court. Instead, the legislature repealed and recreated Wis. Stat. § 74.73(4) (1953), to permit a circuit court action for any excessive assessment under § 74.73(4) (1955). See ch. 440, Laws of 1955. Wisconsin Stat. § 70.47(9a) (1953) was left intact and was later renumbered as § 70.47(13). See § 878, ch. 34, Laws of 1979. This request and subsequent action by the legislature shows that the legislation's intent was to provide property owners with a full court trial when challenging their assessment, which was significantly different than the existing certiorari review.
¶ 28. The Village argues that an equal protection violation is not present because the board of review provides adequate due process to property owners. We interpret this argument to allege that no disparate treatment exists because property owners are essentially afforded the same process at the board of review as they are in a circuit court action. Our primary focus, however, is in comparing the differences between certi-orari review and a court trial. However, even when comparing the board of review hearing to a court trial on an excessive assessment, it is apparent that a trial offers significant safeguards that provide further advantages to property owners who may pursue such court actions.
¶ 29. First, a court trial allows property owners to present their case in a forum that is conducted according to the rules of evidence and discovery. In contrast, evidence is not presented in this manner at the board. In particular, at the board hearing, evidence is presented only through sworn, oral testimony, Wis. *107Stat. § 70.47(8), and only the board may compel production of documents, § 70.47(8)(d). Such informal proceedings may lead to an incomplete or an inadequate record. See Hemker, 114 Wis. 2d at 323. Nevertheless, the board renders a decision based on this record.
¶ 30. Second, at a court trial, property owners can subpoena witnesses to testify at trial. In contrast, at the board of review hearing, only the assessor is required to appear, Wis. Stat. § 70.48, and only the board may, and upon the request of the assessor shall, subpoena other witnesses to appear, Wis. Stat. § 70.47(8)(d).
¶ 31. Third, a court trial is conducted by a judge; the board of review proceedings are not necessarily conducted by such legal professionals who are versed in the rules of evidence. The membership and organization of the board of review varies depending on the size of the municipality and the nature of the assessment system, and the board may contain any number of town, city, or village residents; public officers; and public employees. See Wis. Stat. § 70.46(1).
¶ 32. Fourth, property owners are typically afforded a greater amount of time to prepare their case at the circuit court level than before the board of review. The final assessments by the assessor and the delivery of the assessment roll takes place only a short time before the board of review meets.11 Indeed, notice *108must be provided to property owners 15 days before the board meeting when property is assessed at a different value than the previous year. Wis. Stat. § 70.365. However, property owners are then immediately required to file an objection before the meeting, and the board only has to provide property owners with 48 hours notice before the hearing. See Wis. Stat. § 70.47(3)(a)5., (7)(a). The additional time afforded through a court trial enables property owners to better prepare their case.
¶ 33. On the whole, these differences show that a property owner who is permitted to pursue a circuit court action is treated significantly different than property owners who are limited to mere certiorari review in the circuit court. Thus, having reached this conclusion, we continue to the next step of our equal protection analysis: rational basis.
¶ 34. In addressing whether the legislature had a rational basis in establishing the classification under Wis. Stat. § 74.37(6), Nankin asks us to look at where the legislature drew the "line of demarcation" for the classification, that is, the line that separates the favored and disfavored classes. We examined a similar "line of demarcation" in Milwaukee Brewers for purposes of equal protection analysis. Milwaukee Brewers, 130 Wis. 2d at 104-05. In this case, Nankin correctly asserts that the line is drawn at the county border, based on the population of the county. The question then becomes whether there is a rational explanation for the legislature to have drawn the line at this border *109under a statute that affords property owners the right to challenge their property assessments made by a municipality within that border.
¶ 35. We have upheld classifications based on population on several occasions. See, e.g., Libertarian Party v. State, 199 Wis. 2d 790, 546 N.W.2d 424 (1996) (per curiam); Johnson v. City of Milwaukee, 88 Wis. 383, 60 N.W. 270 (1894). In fact, we have noted that it is no longer open to doubt that counties may be classified according to population. Vill. of Whitefish Bay v. Milwaukee County, 224 Wis. 373, 377, 271 N.W. 416 (1937). However, such classifications are not without limitations.
It is a mistaken idea that because classification on the basis of population is sustainable in respect of legislation on certain subjects, it may be appropriate for all purposes of classification in legislative enactments. Such a basis for classification must have a reasonable relation to the purposes and objects of the legislation, and must be based upon a rational difference in the necessities or conditions found in the groups subjected to different laws. If no such relation and differences exist, the classification is invalid.
16B Am.Jur.2d Constitutional Law § 845 (1998) (footnotes omitted); see also Chicago Nat'l League Ball Club, Inc. v. Thompson, 108 Ill. 2d 357, 369, 483 N.E.2d 1245 (1985).
¶ 36. Nankin argues that the line of demarcation is irrational in this case because property assessments and reviews of these assessments are conducted at the municipal government level, not at the county level. In light of this fact, Nankin asserts that it may have been rational for the legislature to have drawn the line based on the population of the municipality and *110thereby restricting some municipalities from pursuing an action under Wis. Stat. § 74.37(3)(d). However, it was irrational for the legislature to have drawn the line at the county border, and therefore, it is a violation of equal protection.
¶ 37. A review of the legislative history for Wis. Stat. § 74.37(6) and its predecessor Wis. Stat. § 74.73(4) (1965) shows that the legislature did not articulate any rationale for its classification. Therefore, we are obligated to construct a rationale. To aid in our determination, the Village offers two reasons for the classification. First, it asserts that the judicial workload in a county with a large population is substantially more than in a county with a small population, and by prohibiting § 74.37(3)(d) actions in counties with a large population, the judicial workload becomes more manageable. Second, it argues that, by restricting owners of property located in counties with a large population to certiorari actions, review of these assessments may occur at a faster pace, because circuit courts must give preference to such certiorari actions. See Wis. Stat. § 70.47(13). This is important, the Village asserts, because it depends on the tax collected on property for their budgets.
¶ 38. We conclude that neither explanation serves as a rational basis for the classification. In short, judicial workload and timely resolution of property assessments are concerns of all counties. Certainly, the volume of cases in the circuit court differs between counties; however, as Nankin asserts, the legislature has sought to offset such disparities between counties by awarding each county a certain amount of judicial branches depending on such volume. See Wis. Stat. § 753.06.
*111¶ 39. We have stated that a legislative classification will satisfy the rational basis standard if it meets the following five criteria:
(1) All classificationts] must be based upon substantial distinctions which make one class really different from another.
(2) The classification adopted must be germane to the purpose of the law.
(3) The classification must not be based upon existing circumstances only. [It must not be so constituted as to preclude addition to the numbers included within the class].
(4) To whatever class a law may apply, it must apply equally to each member thereof.
(5) That the characteristics of each class should be so far different from those of other classes as to reasonably suggest at least the propriety, having regard to the public good, of substantially different legislation.
Aicher, 2000 WI 98, ¶ 58 (alterations in original). Under this test, the first, second, and fifth criteria are not satisfied.
¶ 40. The classification under Wis. Stat. § 74.37 is based upon the population of a county. Thus, applying the first factor, population must constitute a substantial distinction, such that it makes the class created by the statute really different from other classes. We have indicated that population constitutes a substantial distinction when the classes have different needs, conditions, or requirements with respect to purposes of the legislation such that a statutory classification is justified to account for these differ-*112enees. See Johnson, 88 Wis. at 390-91; cf. City of Brookfield v. Milwaukee Metro. Sewerage Dist., 144 Wis. 2d 896, 916, 426 N.W.2d 591 (1988).
¶ 41. In this case, however, population does not constitute a substantial distinction that makes one class really different from another. There is nothing inherent about populous counties to justify the classification in the statute that restricts the manner in which owners of property located in such counties may challenge their assessments. Populous counties do not afford any additional means to address property assessments such that a Wis. Stat. § 74.37 action is unnecessary in such counties. Moreover, populous counties do not present any special problems or concerns such that it is rational to restrict such circuit court actions in populous counties. Indeed, owners of property located in populous counties — particularly owners of property located in towns, villages, and small cities in the county — have as great an interest in obtaining a court trial on their property assessment as owners of property located in other counties in the state. There is no reason why an owner of property located in the Village of Shorewood in Milwaukee County should be treated differently than an owner of property in the Village of Amherest in Portage County with respect to challenging their property assessments. No substantial distinction exists.
¶ 42. The second factor is also not met in this case because the classification is not germane to the purpose of the law. The purpose of the law is to afford property owners a means to challenge their property assessments. Assessments and board of review hearings are conducted at the municipal level. There is no justification for using the population of a county in legislation that is based on a municipal function. Fur*113ther, as mentioned, there is no justification in prohibiting only owners of property in populous counties from challenging their property assessments under Wis. Stat. § 74.37. Judicial resources in all counties are equally burdened by § 74.37 actions; it cannot be said that populous counties, with their additional judicial resources, are in need of greater relief in this respect” than other counties.
¶ 43. Finally, the fifth prong of the test is also not met. Under this prong, we examine whether the characteristics of each class are so far different as to reasonably suggest at least the propriety, as to the public good, of substantially different legislation. This factor is based on the following reasoning:
"The true practical limitation of the legislative power to classify is that the classification shall be based upon some apparent natural reason, — some reason suggested by necessity, by such a difference in the situation and circumstances of the subjects placed in different classes as suggests the necessity or propriety of different legislation with respect to them."
State ex rel. Risch v. Bd. of Trs. of Policemen's Pension Fund, 121 Wis. 44, 54, 98 N.W. 954 (1904) (quoting Nichols v. Walter, 37 Minn. 264, 272, 33 N.W. 800 (1887)). We are unable to identify any difference in situation or circumstance between properties located in populous counties and properties located in other counties in the state that would necessitate different legislation for the classes in challenging their property assessment. Properties in both classes are assessed and reviewed in the same manner, regardless of the population of the county in which the property is located. Again, there is nothing to distinguish property situated in Shorewood from property located in any *114other village throughout the state with respect to the assessment of property. Thus, an analysis under these factors supports our conclusion that this classification is not supported by a rational basis.
¶ 44. Certainly, the legislature may create a classification in a statute based on population. In fact, we upheld such a classification in State ex rel. Johnson v. Cady, 50 Wis. 2d 540, 185 N.W.2d 306 (1971).12 Cady involved a dispute over whether a certain legislative scheme for providing revocation hearings to probationers violated equal protection. Id. at 550-51. The scheme provided that probationers in counties with a population of less than 500,000 would be in the legal custody of an administrative agency while probationers with a population of 500,000 or more would be in the custody of the probation departments of the criminal branches of the circuit courts. Id. at 552. As a result, probationers in small counties would receive an administrative hearing, while probationers in large counties would receive a judicial hearing. Id. at 551. We noted that such classifications by population violated equal protection only where they were found irrational and arbitrary, that is, where the legislature abused its discretion beyond a reasonable doubt. Id. at 552. We concluded by stating that "[w]e are not convinced that a classification established by the legislature, which provides for different procedures in counties having a population of more than 500,000, is irrational or arbitrary. Thus, the difference in procedure does not offend the constitutional provisions requiring equal protection of the law." Id. at 553.
*115¶ 45. The Village argues that Cady supports its position that the classification under Wis. Stat. § 74.37(6) does not violate equal protection. However, the differences in procedure in Cady did not meet the high standard required for proving an equal protection violation. Since Cady, however, we have determined that substantial differences in procedure may offend equal protection guarantees in certain instances if there is no rational basis to support these differences. See Milwaukee Brewers, 130 Wis. 2d at 106 (finding that two legislative provisions relating to administrative and judicial review procedures violated equal protection). In this case, Nankin has likewise proven beyond a reasonable doubt that the classification at issue violates equal protection because it treats members of classes significantly different without a rational basis. In turn, although Cady shows that classifications by population are permissible in some cases, it does not limit our holding in this case.
¶ 46. In sum, we conclude that the statute's disparate treatment of Nankin and other owners of property located in populous counties is without a rational basis, and as a result, the statute violates equal protection.
¶ 47. We recognize that our determination — that Wis. Stat. § 74.37(6) violates equal protection — is in direct contrast to the conclusion reached in S.C. Johnson. In S.C. Johnson, relying on Cady, the court of appeals concluded that "[g]iven the deference which the law accords classifications based on population, we see nothing irrational or arbitrary in the legislative scheme at issue in this case." S.C. Johnson, 206 Wis. 2d *116at 308. However, based on. our analysis above, we find the statute both irrational and arbitrary, and therefore, we conclude that S.C. Johnson incorrectly decided this issue. As a result, we overrule that portion of S.C. Johnson.
SEVERABILITY
¶ 48. The legislature provides for the severability of statutes under the general rules of statutory construction. Specifically, Wis. Stat. § 990.001(11) provides:
The provisions of the statutes are severable.
The provisions of any session law are severable. If any provision of the statutes or of a session law is invalid, or if the application of either to any person or circumstance is invalid, such invalidity shall not affect other provisions or applications which can be given effect without the invalid provision or application.
Thus, this language generally allows for severability when the invalid section can be severed without affecting the remainder of the statute.
¶ 49. We have likewise stated that severability is appropriate under such circumstances. However, we have required that an examination of legislative intent must take place first:
"Whether an unconstitutional provision is sev-erable from the remainder of the statute in which it appears is largely a question of legislative intent, but the presumption is in favor of severability." "Unless it is evident that the Legislature would not have enacted those provisions which are within its power, independently of that which is not, the invalid part may be dropped if what is left is fully operative as a law."
*117State v. Janssen, 219 Wis. 2d 362, 379, 580 N.W.2d 260 (1998) (citations omitted).
¶ 50. The legislative history of Wis. Stat. § 74.37(6), including the history of its predecessor Wis. Stat. § 74.73(4) (1955), reveals that the classification has been a part of the statute since 1955, when claims for excessive assessment were first permitted in the circuit court. See ch. 440, Laws of 1955. However, nothing in the legislative history reveals that the legislature intended that any part of the statute would not be severable from the whole. Indeed, as § 74.37 currently stands, subsection (6) may be severed and the remainder of the statute will remain fully operative. Thus, because the legislature has not indicated its intent otherwise, we conclude that § 74.37(6) is severa-ble from the remainder of the statute.
CONCLUSION
¶ 51. Based on our analysis above, we conclude that Nankin has met his burden of proving that Wis. Stat. § 74.37(6) is unconstitutional as a violation of equal protection. The classification established in this statutory section treats members of the class significantly different than members outside the class. We cannot determine any rational basis for this disparate treatment. Accordingly, we find this statutory section unconstitutional. We reverse the decision of the court of appeals and grant summary judgment in favor of Nankin. We also grant Nankin's request for a permanent injunction to allow him to file a claim under § 74.37 with the Village. We deny his request for costs associated with this case.
By the Court. — The decision by the court of appeals is reversed.
*118¶ 52. DIANE S. SYKES, J., did not participate.All subsequent references to the Wisconsin Statutes are to the 1997-98 version -unless otherwise indicated.
See Hermann v. Town of Delavan, 215 Wis. 2d 370, 379-80, 572 N.W.2d 855 (1998).
A "taxation district" is defined as "a town, village or city in which general property taxes are levied and collected." Wis. Stat. § 70.045.
Nankin did not pursue his Article VIII, Section 1 claim on appeal.
Equal protection is guaranteed under Article I, Section 1 of the Wisconsin Constitution, which states: “All people are born equally free and independent, and have certain inherent rights; among these are life, liberty and the pursuit of happiness; to secure these rights, governments are instituted, deriving their just powers from the consent of the governed." "This court applies the same interpretation to the state Equal Protection Clause as that given to the equivalent federal provision." Tomczak v. Bailey, 218 Wis. 2d 245, 261, 578 N.W.2d 166 (1998).
First class cities have special provisions for their assessors. Wis. Stat. § 70.06. Classes of cities are defined by statute. See Wis. Stat. § 62.05.
In first class cities and certain second class cities, a board of assessors will hear complaints before objections are brought before a board of review. See Wis. Stat. §§ 70.07, 70.075, 70.47(16).
Our discussion of certiorari review of the board of review's decision applies equally for certiorari review of the department of revenue's decision. Wisconsin Stat. § 70.85(4)(c) does not expand on the grounds for certiorari review. Therefore, it is appropriately defined, similar to Wis. Stat. § 70.47(13) review, under common law certiorari. See Hanlon v. Town of Milton, 2000 WI 61, ¶ 23, 235 Wis. 2d 597, 612 N.W.2d 44; State ex rel. Wis. River Power Co. v. Bd. of Review of Armenia, 125 Wis. 2d 94, 97, 370 N.W.2d 580 (Ct. App. 1985).
In S.C. Johnson & Son, Inc. v. Town of Caledonia, 206 Wis. 2d 292, 301, 557 N.W.2d 412 (Ct. App. 1996), the court of appeals referred to a Wis. Stat. § 74.37(3)(d) action as a "trial de novo." This was incorrect. "A trial de novo is a new trial in which the whole case is retried as if no trial whatsoever had been had in the first instance." Vill. of Menomonee Falls v. Michelson, 104 Wis. 2d 137, 149, 311 N.W.2d 658 (Ct. App. 1981). Although assessments are contested at the board of review, such board hearings cannot be said to be the same as a court trial, which is permitted under to § 74.37.
The other statutes included Wis. Stat. § 70.47(13) (1953), which, like the current § 70.47(16), provided for special objection procedures for residents of first class cities, and Wis. Stat. § 70.85 (1953), which, similar to the current § 70.85, permitted property owners to challenge the valuation of their assessment before the department of taxation. Section 70.85 (1953), however, did not provide for certiorari review in the circuit court.
Property assessment must be handled in a timely manner by the assessor. Assessors must assess all real and personal property as of the close of January 1 of each year. Wis. Stat. § 70.10. Except in first and second class cities that have a board of assessors, the assessments must be completed before the first Monday in April, Wis. Stat. § 70.10, and the assessor must deliver the completed roll and all sworn statements and valua*108tions of personal property to the clerk of the taxation district by the first Monday in May, Wis. Stat. § 70.50. The board then is required to meet at any time during the 30-day period beginning on the second Monday of May. Wis. Stat. § 70.47(1).
See also City of Marshfield v. Town of Cameron, 24 Wis. 2d 56, 62-64, 127 N.W.2d 809 (1964) (upholding classifications based on county population where the statute pertained to apportionment of public utility taxes to school districts).