[¶1] Solvay Chemicals, Inc. (Solvay) appealed the Department of Revenue's (DOR) assessment of the taxable value of soda ash produced at its Sweetwater County trona mine to the Wyoming Board of Equalization (Board). Solvay disputed the calculations the DOR used to determine the amount of the deduction for bagging some of the soda. After the contested case hearing, the Board requested supplemental briefs to address a question of statutory construction that had not been raised by either party, and the Board ultimately decided that the issue was not the amount Solvay was entitled to deduct for bagging costs, but rather, whether it was entitled to any bagging deduction at all. The Board concluded that the issue disputed by *297the parties throughout the proceeding was moot, reasoning that the governing statute did not allow for a separate deduction for bagging. We decline the parties' request that we decide the issue of statutory interpretation as it applies to bagging cost deductions, because we find that the Board exceeded its authority when it decided an issue that was not before it.
ISSUE
[¶2] One issue raised by the parties is dispositive: Whether the Board acted without observance of the procedure required by law when it based its order on an issue not contested or addressed by either party during the contested case hearing.
FACTS
[¶3] Solvay mines trona ore from its mine in Sweetwater County, Wyoming, and then processes it as soda ash and other products. Solvay sells the majority of its soda ash in bulk, and transports it to the customer by rail or truck. A small amount of Solvay's soda ash is bagged and provided to customers in that form, at a higher charge. Solvay incurs increased costs for the bagging, and it historically deducted those costs from the sales value for tax purposes. Solvay's practice was to report the taxable value of its bagged product based on the bulk product value. But, after an audit of Solvay's 2010-2012 production and tax payments, the Department of Audit (DOA) rejected Solvay's approach and instead arrived at a lower bagging deduction, based on its calculation of Solvay's actual bagging costs. The DOR adopted the DOA's calculations and issued its final determination assessment notice of additional severance tax due, notifying Solvay of an additional $24,524 due in severance taxes, and interest in the amount of $13,160.
[¶4] The primary issue identified in Solvay's Notice of Appeal was "Solvay believes DOR and DOA may not have properly valued a portion of Solvay's trona/soda ash production known as 'bagged product.' " In its Preliminary Statement, Solvay again summarized its contention as "DOR's and DOA's valuation of Solvay's 'bagged product' is erroneous." The DOR agreed, identifying the first issue of fact and law in its Preliminary Statement as "Did the [DOR] correctly value the bagged sales of soda ash in accordance with the law?" The correct valuation of Solvay's deduction for bagging soda ash to determine taxable value continued to be the central issue identified by both parties in their pre-hearing filings, at the hearing, and in the parties' post-hearing briefs and proposed findings of fact and conclusions of law.
[¶5] Nearly five months after the hearing, the Board, in its Order for Supplemental Briefing, signaled that it did not consider the calculation of the deduction for Solvay's bagged product to be the issue; instead, the Board ordered the parties to submit briefs answering its questions on statutory interpretation regarding an entirely different methodology. The Board ordered the parties to submit supplemental briefs on these issues:
1. Are relevant parts of Wyoming Statutes sections 39-14-301 and 303 (2009-2012) ambiguous and, if so, in what respect?
2. Do the provisions in Wyoming Statute section 39-14-303(b) (2009-2012) identify multiple valuation methods, or a single valuation method? If you argue that subsection (b) prescribes one valuation method, please explain and reconcile the remaining subsection (b) provisions in support of your interpretation. If you argue that subsection (b) offers more than one valuation method, please identify and explain the application of those methods and how those differ from, or relate to, subsection (b)(ii).
[¶6] The parties agreed that the statutes were unambiguous, so the first issue was not in dispute. As to the second question, a brief discussion of the statutory interpretation issue is necessary to set the stage.
*298
(b) Basis of tax (valuation). The following shall apply:
(i) Trona shall be valued for taxation as provided in this section;
(ii) The department shall calculate the value of trona ore for severance and ad valorem tax purposes by using the individual producer's fair market value of soda ash f.o.b. plant multiplied by the industry factor divided by the individual producer's trona to soda ash ratio less exempt royalties. The industry factor shall be thirty-two and five-tenths percent (32.5%);
(iii) The value of the gross product shall be the fair market value of the product at the mouth of the mine where produced, after the mining or production process is completed;
(iv) Except as otherwise provided, the mining or production process is deemed completed when the mineral product reaches the mouth of the mine. In no event shall the value of the mineral product include any processing functions or operations regardless of where the processing is performed;
(v) Except as otherwise provided, if the product as defined in paragraph (iv) of this subsection is sold at the mouth of the mine, the fair market value shall be deemed to be the price established by bona fide arms-length sale;
(vi) When the taxpayer and department jointly agree that the application of the methods listed in paragraphs (i) through (v) of this subsection does not produce a representative fair market value for the product, a mutually acceptable alternative method may be applied. Not later than October 1 of each year, the department shall report to the joint minerals, business and economic development interim committee and the joint revenue interim committee on any action taken under this paragraph.
[¶7] Section (b)(ii) adopts an "industry factor" test whose objective was to standardize the deductions for all trona companies and simplify what had been complicated calculations by the producers, the DOA, and the DOR. Up until the Board's Order for Supplemental Briefing, Solvay and the DOR had agreed that Solvay was entitled to a deduction for bagging costs under (b)(iv), in addition to the "industry factor" deduction at (b)(ii). The DOR's new position, in response to the Board's Order for Supplemental Briefing, was that Solvay was entitled to no additional deductions for bagging costs under (b)(iv), because "a more reasoned (and legally accurate) approach is to consider any and all incurred bagging expenses to be encompassed within the scope of the 32.5% industry factor" at (b)(ii) (a single valuation method). Solvay continued to argue that section 303(b)(iv) allowed it to deduct the costs of bagging, in addition to the industry factor deduction at 303(b)(ii) (multiple valuation methods), and it urged the Board to order the DOR to apply its approach to calculating those costs. Solvay filed a response brief, in which it strenuously objected to the DOR's new position, as well as to the timing of raising the new approach.
[¶8] The Board heard oral argument on the new issue. Solvay again objected to the substance and the procedure of the DOR's new approach. At that hearing, the Board chairman expressed his concerns about the Board's jurisdiction in light of the DOR's new assessment.
I just know that we don't have jurisdiction if there -- if the parties are no longer disputing from a final action. So at that point -- I mean, I know what the answer is from our perspective. We don't have jurisdiction.
[¶9] The Board apparently resolved those jurisdictional concerns to its satisfaction, and in its Findings of Fact, Conclusions of Law, Decision and Order, it concluded that Solvay was not entitled to any deduction for bagging soda ash, and it held that the parties' dispute "over how to calculate an additional processing deduction ... is moot in light of our determination that the [DOR] and Solvay initially misinterpreted the underlying valuation methodology." It ordered that the DOR's audit assessment was "reversed and remanded to the [DOR] for reassessment in *299accordance with" its decision. (Emphasis omitted.)
[¶10] Solvay timely petitioned for review of the Board's action, the district court granted the parties' joint motion to certify the case to the Wyoming Supreme Court, and this Court accepted the certified case pursuant to W.R.A.P. 12.09.
DISCUSSION
[¶11] Judicial review of administrative actions is generally governed by
[¶12] The Board of Equalization is created by the Wyoming Constitution, which requires the legislature to "provide by law for a state board of equalization," Wyo. Const. art. 15, § 9, and describes the Board's duties as "to equalize valuation on all property ... and such other duties as may be prescribed by law." Wyo. Const. art. 15, § 10. Historically, the Board performed valuation functions, but in 1991, the legislature separated the Department of Revenue and Taxation from the Board and assigned "the valuation of property for tax assessment" to the DOR instead of the Board. Union Pac. Res. Co. v. State Bd. of Equalization ,
[¶13] Although the Board is a quasi-judicial body, the DOR's contention that "the Board should be treated in the same manner as any other judicial body when construing statutes affecting the assessment, levy and collection of taxes" is incorrect. The Board is not, in fact, like any other judicial body; rather, it is a creature of the legislature. "An administrative agency is limited in authority to powers legislatively delegated. Administrative agencies are creatures of statute and their power is dependent upon statutes, so that they must find within the statute warrant for the exercise of any authority which they claim." Exxon Mobil Corp ,
[¶14] In UPRC II , UPRC petitioned the Board to declare the point of valuation to determine taxable value for oil and gas production, and the Board declined to exercise jurisdiction.
[¶15] The court reminded the Board of the limitations on its authority in Basin Electric Power Cooperative, Inc. v. Department of Revenue ,
[¶16] In Antelope Valley Improvement and Service District v. State Board of Equalization ,
[¶17] In Amoco III , the court considered the limits of the Board's authority in the context of a decision it made in its adjudicatory capacity. Amoco appealed the DOR's determination of the amount it owed for taxes, interest, and penalties on natural gas production. Id .,
It is only by either approving the determination of the Department, or by disapproving the determination and remanding the matter to the Department, that the issues brought before the Board for review can be resolved successfully without invading the statutory prerogatives of the Department.
[¶18] Here, Solvay and the DOR agreed that bagging costs should be deducted pursuant to
[¶19] Just as in Amoco III ,
[Solvay] correctly argues that this case was before the Board for a decision on *301whether certain deductions were or were not allowable. We have no occasion to divest the Board of its prerogatives in the resolution of that question, but we do hold that the Board must decide the question before it in accordance with applicable law. It must refrain from usurping the valuation function assigned to the [DOR], even if the [DOR] should acquiesce.
[¶20] The Board here recognized that "the [DOR] could not, after the hearing, supplant, negate or materially modify the audit assessment with an alternative decision to be applied in the present appeal." The only way for the DOR to change the decision appealed would have been for it "to withdraw its audit assessment and issue a revised assessment, or otherwise obtain Solvay's consent to such change."
[¶21] The DOR also relies on the "decide all questions" language at
(a) The state board of equalization shall perform the duties specified in article 15, section 10 of the Wyoming constitution and shall hear appeals from county boards of equalization and review final decisions of the department upon application of any interested person adversely affected, including boards of county commissioners for the purposes of this subsection, under the contested case procedures of the Wyoming Administrative Procedure Act. ... In addition, the board shall :
(xiv) Carefully examine into all cases wherein it is alleged that property subject to taxation has not been assessed or has been fraudulently, improperly, or unequally assessed, or the law in any manner evaded or violated, and cause to be instituted proceedings which will remedy improper or negligent administration of the tax laws of the state[.]
[¶22] Section 14 is not at issue in the present case (it now appears as
[¶23] The relevant language of
(c) The state board of equalization shall perform the duties specified in article 15, section 10 of the Wyoming constitution and shall hear appeals from county boards of equalization and review final decisions of the department upon application of any interested person adversely affected ... under the contested case procedures of the Wyoming Administrative Procedure Act. ... In addition, the board shall :
....
(iii) When in the opinion of the board, it would be of assistance in equalizing values under paragraph (ii) of this subsection, the board may require any county assessor to furnish statements showing assessments of the property of any person within the county. The board shall consider and equalize county assessments under paragraph (ii) of this subsection and may increase or decrease assessments returned by the county board of equalization when the property so assessed appears to be over-valued or under-valued, first giving notice to those persons affected. The notice shall fix a time and place of hearing. Any affected person may appeal from the decision of the board to the district court of the county in which the property is situated .
(iv) Decide all questions that may arise with reference to the construction of any statute affecting the assessment, levy and collection of taxes, in accordance with the rules, regulations, orders and instructions prescribed by the department:
(A) Upon application of any person adversely affected ; or
(B) In performing its responsibilities to equalize values, including with respect to the suitability of the system prescribed by the department for establishing fair market value.
(Emphasis added.)
[¶24] We find, as the court did in Exxon ,
[¶25] In addition, the "[d]ecide all questions language" at (c)(iv) is only triggered either upon application of any person adversely affected, or in performing equalization functions. Neither of those prerequisites exists here. The Board was not performing equalization functions, and there was no application by a person adversely affected to *303decide the question that the Board ultimately decided. Solvay was the person adversely affected, and it never sought the Board's construction of the statute to determine whether it was entitled to a bagging deduction at all; it only requested a contested case hearing to challenge the DOR's valuation of its bagging deduction. The Board's authority was limited to adjudicating the dispute between Solvay and the DOR. Amoco III ,
[¶26] In its zeal to correct what it saw as an incorrect application of the law, the Board abandoned the established procedural rules in tax appeals.
With regard specifically to valuations of property by DOR for purposes of taxation, we have recently noted:
The Department's valuations for state-assessed property are presumed valid, accurate, and correct. This presumption can only be overcome by credible evidence to the contrary. In the absence of evidence to the contrary, we presume that the officials charged with establishing value exercised honest judgment in accordance with the applicable rules, regulations, and other directives that have passed public scrutiny, either through legislative enactment or agency rule-making, or both.
The petitioner has the initial burden to present sufficient credible evidence to overcome the presumption, and a mere difference of opinion as to value is not sufficient. If the petitioner successfully overcomes the presumption, then the Board is required to equally weigh the evidence of all parties and measure it against the appropriate burden of proof. Once the presumption is successfully overcome, the burden of going forward shifts to the DOR to defend its valuation. The petitioner, however, by challenging the valuation, bears the ultimate burden of persuasion to prove by a preponderance of the evidence that the valuation was not derived in accordance with the required constitutional and statutory requirements for valuing state-assessed property.
Moreover, in examining the propriety of the valuation method, our task is not to determine which of the various appraisal methods is best or most accurately estimates fair market value; rather, it is to determine whether substantial evidence exists to support usage of the chosen method of appraisal.
Airtouch Commc'ns, Inc. v. Dep't of Revenue ,
[¶27] The Board's authority is limited to "review[ing] final decisions of the [DOR] upon application of any person adversely affected."
CONCLUSION
[¶28] The Board had the authority to adjudicate the dispute between Solvay and the DOR, and not to arrive at its own valuation by questioning the statutory approach the parties had agreed upon. We therefore reverse the decision of the Board, and remand for proceedings in accordance with this opinion.
[¶29] I disagree with the majority that the Wyoming Board of Equalization (Board) exceeded its authority when it interpreted
[¶30] The majority framed the dispositive issue as one raised by the parties: "Whether the Board acted without observance of the procedure required by law when it based its order on an issue not contested or addressed by either party during the contested case hearing." (Emphasis added.) The majority held, however, that the "Board exceeded its authority when it decided an issue that was not before it." Notably, neither Solvay nor the Department of Revenue (DOR) argued or even hinted that the Board had exceeded its statutory authority by prompting a closer examination of how the legislature intended the statutory valuation provisions in
I. Statutory Construction Issue Properly Before the Board Even Under the Majority's Reading of the Statute
[¶31] The Board often is tasked with interpreting tax valuation statutes in both adjudicatory
[¶32] After the close of evidence, the Board identified specific statutory interpretation questions to be answered before it could apply the statute to the evidence presented. The Board requested that the parties brief the following, summarized issues: (1) whether relevant parts of trona valuation statutes,
*306II. Alternatively, the Majority's Reading of the Statute Improperly Limits Board's Authority
[¶33] To the extent the majority's test for when the Board has authority to interpret
A.
[¶34] In listing the Board's primary constitutional and statutory duties, the legislature mandates that the Board shall review "final decisions of the [DOR] upon application of any interested person adversely affected."
[¶35] It is axiomatic that an administrative agency, including a quasi-judicial administrative body like the Board, is generally clothed with the power and duty to interpret the statutes it executes, not just through rulemaking, but also through the exercise of its adjudicative powers.
[¶36] The majority's conclusion that -102.1(c)(iv) "is more closely aligned" with the Board's regulatory duty to equalize values and that "[s]ubsections (c)(iii) and (iv) are directed to the Board's regulatory function to equalize values," is unsupported by statutory language and structure.
[¶37] Moreover, the "may arise" language found in -102.1(c)(iv) modifies "questions ... with reference to the construction of any statute affecting the assessment, levy and collection of taxes," not the context (adjudicatory -102.1(c)(iv)(A) or regulatory -102.1(c)(iv)(B) ) in which the question comes to the Board. The phrase "may arise" therefore cannot support the specificity requirement in the majority's conclusion that "there was no application by a person adversely affected to decide the question that the Board ultimately decided." Consequently, the Board did not impermissibly expand its adjudicatory authority when it concluded Solvay was entitled to the industry factor under
[¶38] Considering the scope and arrangement of the remaining subsections of
[¶39] Our precedent is not to the contrary. For example, in Union Pacific Resources Company v. State Board of Equalization ,
[¶40] Similarly, the Board's statutory construction in this case is easily distinguished from the Board's unauthorized, investigative factfinding into the DOR's methods of appraising rural electric cooperative utilities struck down in Basin Electric Power Cooperative, Inc. v. Department of Revenue ,
[¶41] The dispositive statutory construction issue in this case also is easily distinguished from the holding in Antelope Valley Improvement and Service District v. State Board of Equalization ,
[¶42] Nor do the limitations on the Board's authority discussed in Amoco Production Company v. Wyoming State Board of Equalization ,
[¶43] In Amoco III , we looked at whether the Board invaded the DOR's statutory authority,
[¶44] Amoco III would govern this case if the Board had preferred Solvay's "bulk product" methodology or fashioned a bagging cost deduction methodology of its own rather than considering the DOR's "actual cost" methodology presumptively valid, see infra n.14. But that is not what happened here. Instead of second-guessing the DOR's bagging cost deduction methodology or choosing another methodology, the Board turned to the governing statute and ruled that the legislature did not intend to provide Solvay a separate bagging cost deduction at all. The Board's disapproval of the DOR's assessment to the extent it allowed any separate processing deduction for bagging costs, and its order remanding the assessment to the DOR, is entirely consistent with Amoco III and is in accordance with applicable law. We must apply language from Amoco III and other cited cases in the context of the specific issues considered and decided in each case. To confuse the boundaries of the Board's statutory authority recognized in those cases with the Board's duty and authority to interpret the *309trona valuation statutes does an injustice to the Board and to Wyoming administrative law.
[¶45] An administrative agency, including a quasi-judicial administrative body like the Board, is bound to follow its governing statutes. Thunder Basin Coal Co. ,
B. Practical Considerations
[¶46] The key consideration is: Why would this Court force a construction of
[¶47] Courts and agency bodies with appellate functions have the power to review matters not raised below, though they may choose to exercise such power sparingly. See , e.g. , MaineGeneral Med. Ctr. v. Shalala ,
[¶48] If, as the majority concludes, the Board is prohibited from construing tax valuation statutes when adjudicating appeals from DOR decisions, "persons adversely affected" may avoid raising those statutory issues in their notices and pleadings on which they do not believe they will prevail. Under the majority's view, unless the parties noticed and pled a disputed statutory construction issue with particularity, the Board would have to perpetuate an incorrect statutory interpretation until reversed on judicial review or by regulatory action.
*310[¶49] In addition, the majority opinion could encourage parties to file original court actions to resolve statutory interpretation questions; whereas, in the past, the Board has repeatedly and properly applied
CONCLUSION
[¶50] For all the foregoing reasons, I conclude the Board did not exceed its authority when it interpreted
Notes
This was based on a finding of increased taxable value of $613,086 for the period.
The DOR's attorney conceded at oral argument that this was not a desirable option because the DOR may have been out of time to issue a revised assessment. See
See Board of Equalization Rules, Chapter 5: Equalization Standards and Procedures (Local Assessments), setting forth the procedure for the Board to "annually determine whether each county is in compliance with the fair market value standard and, if noncompliance is found, establish procedures for equalizing property values or otherwise reducing the inequitable assessment bias."
The DOR warns that this result would force the Board to perpetuate illegal and incorrect applications of the law, but the Board has the authority to correct such errors in its rulemaking capacity. Further, the tax assessment at issue here was for production years 2010-2012. We are confident that, now that the DOR believes it has discovered the correct statutory interpretation, it will be assessing taxes for subsequent years using its new approach, and the Board will have the opportunity to determine the issues properly raised in an appeal of that final determination.
Solvay argues that the Board's procedure deprived it of due process, but we do not address constitutional issues if we are able to resolve the case on other grounds. Wilson v. Bd. of Cty. Comm'rs of Cty. of Teton ,
See, e.g ., Wyodak Res. Dev. Corp. v. Wyo. Dep't of Revenue ,
See, e.g ., In re Request for Examination by Merit Energy Co. , Docket No. 2010-141,
The majority initially is adamant that
Instead, Solvay and the DOR mechanically applied
As the majority notes, the parties agreed the statutes are unambiguous.
The majority states, "the Board ordered the parties to submit briefs answering its questions on statutory interpretation regarding an entirely different methodology [;]" thus suggesting the Board ventured outside the statute and into the DOR's domain. (Emphasis added.) The Board's order, read in context, makes clear the Board requested additional briefing on "purely legal questions regarding [the parties'] initial agreed application of the industry factor method" and the "basic application of the trona tax valuation statute." The Board expressly recognized it cannot usurp the DOR's valuation or tax administration functions, but exercised its adjudicatory obligation in holding that the DOR acted contrary to statutory language and legislative intent in allowing any bagging cost deduction. The Board's determination that
An agency may not declare a statute void or otherwise unenforceable, cannot invalidate a statute on constitutional grounds, enlarge the scope of or change a properly enacted statute, and cannot modify, abridge or otherwise change the statutory provisions under which it acquires authority. See, e.g. , Platte Dev. Co. v. Envtl. Quality Council ,
The majority's application of the regulatory and adjudicatory distinctions we applied in Exxon Corp. v. Board of County Commissioners ,
The majority further confuses the extent to which established procedural rules in tax appeals apply to the Board's decision in this case. As this Court acknowledged in Airtouch Communications, Inc. v. Department of Revenue ,
Wyo. Bd. of Equalization Rules, ch. 2, § 2 (2006).
See, e.g. , Thunder Basin Coal Co. ,
