CO2 Committee v. Montezuma County , 2021 COA 36 ( 2021 )


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  •      The summaries of the Colorado Court of Appeals published opinions
    constitute no part of the opinion of the division but have been prepared by
    the division for the convenience of the reader. The summaries may not be
    cited or relied upon as they are not the official language of the division.
    Any discrepancy between the language in the summary and in the opinion
    should be resolved in favor of the language in the opinion.
    SUMMARY
    March 18, 2021
    2021COA36
    No. 19CA1798, CO2 Committee v. Montezuma County — Energy
    and Environment — Oil and Gas; Taxation — Property Tax —
    Valuation of Oil and Gas Leaseholds and Lands — Valuation for
    Assessment; Jurisdiction of Courts — Standing
    In this oil and gas leasehold tax case, a division of the court of
    appeals considers whether a nonoperating fractional interest owner
    in an oil and gas unit, who pays real property taxes on its leasehold
    interest, has standing to claim that its due process rights were
    violated when it did not receive individual notice of or an
    opportunity to challenge a retroactive assessment and increased tax
    liability. The division concludes, as a matter of first impression,
    that a nonoperating fractional interest owner who has been denied
    the panoply of rights afforded a taxpayer under the governing
    statutes and guidelines — including to receive notice of and to
    protest a retroactive assessment or to seek an abatement of a
    retroactively increased tax — has standing to claim a violation of
    those rights. The division reverses the district court’s order
    dismissing the complaint for lack of standing.
    COLORADO COURT OF APPEALS                                         2021COA36
    Court of Appeals No. 19CA1798
    Montezuma County District Court No. 18CV30100
    Honorable Todd Jay Plewe, Judge
    CO2 Committee, Inc.,
    Plaintiff-Appellant,
    v.
    Montezuma County, Colorado; Montezuma County Board of County
    Commissioners; Montezuma County Board of Equalization; Montezuma County
    Assessor; and Montezuma County Treasurer,
    Defendants-Appellees.
    JUDGMENT REVERSED AND CASE
    REMANDED WITH DIRECTIONS
    Division II
    Opinion by JUDGE BROWN
    Román and Welling, JJ., concur
    Announced March 18, 2021
    Cogswell Law Offices, John M. Cogswell, Buena Vista, Colorado, for Plaintiff-
    Appellant
    Dufford, Waldeck, Milburn & Krohn, L.L.P., Nathan A. Keever, Jon T. Burtard,
    Grand Junction, Colorado, for Defendants-Appellees
    ¶1    This oil and gas leasehold tax case requires us to determine
    whether a nonoperating fractional interest owner in an oil and gas
    unit who pays real property taxes on its leasehold interest has
    standing to claim that its due process rights were violated when it
    did not receive individual notice of or an opportunity to challenge a
    retroactive assessment and increased tax. We conclude, as a
    matter of first impression, that a nonoperating fractional interest
    owner who has been denied the panoply of rights afforded a
    taxpayer under the governing statutes and guidelines — including
    the rights to receive notice of and to protest a retroactive
    assessment or to seek an abatement of a retroactively increased tax
    — has standing to claim a violation of those rights.
    ¶2    The plaintiff in this case, CO2 Committee, Inc. (CO2), is a
    nonprofit corporation whose members include nonoperating
    fractional interest owners in the McElmo Dome Unit (the Unit) who
    pay real property taxes to Montezuma County.1 Following an audit,
    1 Based on the record before us, the precise composition of CO2’s
    membership is unclear. Because the district court did not take
    evidence or make jurisdictional findings, however, we accept as true
    the allegations in the complaint. Jones v. Samora, 
    2016 COA 191
    ,
    ¶ 21 (“When deciding whether a party has standing, ‘all averments
    1
    Montezuma County2 retroactively increased the assessed value of
    the taxable real property in the Unit for tax year 2008, which
    resulted in an increased tax liability for the Unit.
    ¶3    On behalf of its members, CO2 filed a complaint alleging that
    Montezuma County violated its members’ due process rights by
    failing to provide each member individual notice of and an
    opportunity to challenge the retroactive assessment. The district
    court dismissed the complaint for lack of standing.
    ¶4    We conclude that CO2’s members include nonoperating
    fractional interest owners who are taxpayers with standing to
    pursue the claims asserted in the complaint. Accordingly, we
    reverse the district court’s order dismissing the complaint and
    remand the case for further proceedings.
    of material fact in a complaint must be accepted as true.’” (quoting
    State Bd. for Cmty. Colls. & Occupational Educ. v. Olson, 
    687 P.2d 429
    , 434 (Colo. 1984))); cf. Medina v. State, 
    35 P.3d 443
    , 452 (Colo.
    2001) (explaining that a trial court is authorized to conduct a
    hearing and to resolve disputed jurisdictional facts).
    2 Defendants are Montezuma County, Montezuma County Board of
    County Commissioners, Montezuma County Board of Equalization,
    Montezuma County Assessor, and Montezuma County Treasurer
    (collectively, Montezuma County).
    2
    I.   Background
    ¶5        An estate in minerals such as oil and gas is a form of real
    property. § 24-65.5-101, C.R.S. 2020; § 39-1-102(14), C.R.S. 2020.
    When the owner of a mineral estate leases the right to extract oil
    and gas from the land,
    the lease may create various interests, which
    generally take the form of either a working
    interest (the oil and gas company’s right to
    extract the minerals and develop them for
    profit) or a royalty interest (the estate owner’s
    right to receive a share of the production or a
    share of the value of the proceeds of
    production).
    Kinder Morgan CO2 Co., L.P. v. Montezuma Cnty. Bd. of Comm’rs,
    
    2017 CO 72
    , ¶ 4 (KM II) (citing 1 Patrick H. Martin & Bruce M.
    Kramer, Williams & Meyers, Oil and Gas Law §§ 201-216 (2014
    ed.)).
    ¶6        In the oil and gas context, a “unit” is “a consolidation of
    working interests that extract resources from a single geological
    reservoir. Units are created for the purpose of efficiently extracting
    resources from the reservoir through coordinated engineering and
    operation, often by a single operator.” KM II, ¶ 12 n.4 (citing 6
    Martin & Kramer, § 901); see also § 39-10-106(5), C.R.S. 2020
    3
    (“‘[U]nit’ means any single oil, gas, or other hydrocarbon well or field
    which has multiple ownership, or any combination of oil, gas, or
    other hydrocarbon wells, fields, and properties consolidated into a
    single operation, whether by a formal agreement or
    otherwise . . . .”). The operator is the “person responsible for the
    day-to-day operation of a well by reason of contract, lease, or
    operating agreement.” 3 Div. of Prop. Tax’n, Dep’t of Loc. Affs.,
    Assessor’s Reference Library, at 6.25 (rev. Jan. 2008) (ARL).3
    ¶7    The Unit at issue here is a consolidation of working interests
    in a large deposit of pure carbon dioxide in Montezuma and Dolores
    Counties. KM II, ¶ 12 n.4 (citing Colorado Oil and Gas
    Conservation Commission Order No. 389-1 (Nov. 17, 1982)).
    Although several other individuals and entities own various working
    3 In this opinion, we refer to Volume 2 of the ARL, the
    “Administrative and Assessment Procedures Manual,” revised
    December 2008, and Volume 3 of the ARL, the “Land Valuation
    Manual,” revised January 2008. Volume 2 “is an aid to assessors
    in valuing and assessing taxable property.” 2 ARL Preface, at ii.
    Volume 3 “provide[s] a reference source for appraisal and
    assessment policies and procedures for the valuation of land
    according to the Colorado Constitution and statutes.” 3 ARL
    Preface, at ii. Current and historical versions may be found online:
    Colo. Dep’t of Loc. Affs., Assessors’ Reference Library Manuals,
    https://perma.cc/AVY8-5ME7.
    4
    interests and royalty interests in the Unit, Kinder Morgan CO2
    Company, L.P. (Kinder Morgan) is the largest working interest
    owner and the sole operator of the Unit. Kinder Morgan owns a
    44% fractional interest in the Unit. CO2’s members are royalty
    owners, overriding royalty owners, and nonoperating working
    interest owners collectively owning an 11.224% fractional interest in
    the Unit.
    ¶8    As the Unit operator, Kinder Morgan extracts and compresses
    the carbon dioxide and then transports it by pipeline to Texas
    where it is sold for use in oil and gas operations. See id. at ¶¶ 12-
    13. Kinder Morgan also manages the Unit’s development by paying
    for the facilities and equipment and supplying labor to produce the
    carbon dioxide, and then billing the other working interest owners
    for its expenses in operating the Unit and arranging for
    transportation of the carbon dioxide to the point of sale. Id. at ¶ 13.
    ¶9    As the Unit operator, Kinder Morgan also files an annual
    property tax statement for and pays property taxes on behalf of all
    interest owners in the Unit. Id.; see also § 39-7-101(1), C.R.S.
    2020; § 39-10-106.
    5
    ¶ 10   Oil and gas leaseholds are taxed as real property. KM II, ¶ 4;
    see also Colo. Const. art. X, § 3(1)(b); § 39-7-102, C.R.S. 2020.
    “Unlike most property interests, however, the value of an oil and
    gas leasehold interest comes not from the physical space or land
    the leasehold occupies, but rather, from the quantity and value of
    oil and gas underground.” KM II, ¶ 4. That value, in turn, depends
    on the “selling price of the gas or oil ‘at the wellhead,’” id. at ¶ 7; see
    also §§ 39-7-101(1), -102, a term we discuss in greater detail below
    in Part II.C.2.b.
    ¶ 11   In 2009, following an audit of the annual property tax
    statement Kinder Morgan filed for the Unit for tax year 2008,
    Montezuma County determined that Kinder Morgan had
    underreported the selling price at the wellhead by deducting costs
    that it was not allowed to deduct. KM II, ¶¶ 15-16. Consequently,
    Montezuma County retroactively increased its valuation of the
    leaseholds in the Unit by approximately $57 million, increasing the
    Unit’s property tax liability by over $2 million. Id. at ¶ 16.
    ¶ 12   Kinder Morgan paid the increased taxes under protest,
    petitioned for and was denied an abatement, and unsuccessfully
    appealed the retroactive assessment all the way to the Colorado
    6
    Supreme Court. Id. at ¶¶ 17, 46; see Kinder Morgan CO2 Co., L.P. v.
    Montezuma Cnty. Bd. of Comm’rs, 
    2015 COA 72
    , ¶ 44 (KM I), aff’d,
    KM II. In KM II, the supreme court concluded that “the statutory
    scheme governing property taxation of oil and gas leaseholds and
    lands authorizes the retroactive assessment of taxes when an
    operator has underreported the selling price of oil or gas,” KM II,
    ¶ 40, and affirmed the Board of Assessment Appeals’ conclusion
    that Kinder Morgan had underreported the selling price at the
    wellhead, id. at ¶ 46.
    ¶ 13   Ultimately, Kinder Morgan billed the nonoperating fractional
    interest owners, including CO2’s members, for their proportionate
    shares of the increased taxes. CO2 alleged in its complaint that
    Montezuma County has since retroactively increased its valuation
    of the leaseholds in the Unit and retroactively assessed taxes
    against the Unit for tax years subsequent to 2008. Kinder Morgan
    has paid the increased taxes and billed the fractional interest
    owners, including CO2’s members, for their proportionate shares.
    CO2 alleged that its members have collectively been assessed
    retroactive taxes estimated at $500,000 per year.
    7
    ¶ 14   During the audit of the 2008 tax statement, the retroactive
    assessment, the petition for abatement, and the subsequent
    appeals, Montezuma County communicated only with Kinder
    Morgan as the operator of the Unit. It issued special notices of
    valuation only to Kinder Morgan. It did not provide individual
    notice to any other fractional interest owner and no other fractional
    interest owner participated in the proceedings resulting in the
    increased tax liability.
    ¶ 15   According to its complaint, after CO2 received notice from
    Kinder Morgan that Kinder Morgan had paid increased taxes for the
    Unit, it attempted to challenge the retroactive assessment on behalf
    of its members. In substance, it argued that its members were
    entitled to deduct the costs that Kinder Morgan was disallowed, so
    its members did not underreport their selling price at the wellhead.
    As a result, CO2 argued, Montezuma County improperly increased
    the taxable value of their interests by retroactively assessing the
    entire Unit without making individual proportionality computations
    for each fractional interest owner.
    ¶ 16   CO2 filed an objection with the Montezuma County assessor
    pursuant to section 39-5-122, C.R.S. 2020, claiming that
    8
    Montezuma County wrongfully determined that CO2’s members had
    underreported their selling price at the wellhead beginning with the
    2008 tax year. CO2 alleged that Montezuma County responded,
    claiming it was unable to establish that CO2’s members should be
    treated differently than Kinder Morgan for purposes of computing
    the selling price at the wellhead, and that separate special notices
    of valuation have never been provided to CO2’s members and were
    not required.
    ¶ 17   CO2 then appealed to the board of equalization pursuant to
    section 39-8-106, C.R.S. 2020, and filed a petition for abatement
    with the board of county commissioners pursuant to section 39-10-
    114, C.R.S. 2020. CO2 alleged that Montezuma County responded
    as follows: “The Montezuma County Assessor’s office has not sent
    Notices of Value [to CO2]. As [CO2] is not identified as a
    Montezuma County taxpayer, we are not able to provide a hearing
    at the [b]oard of [e]qualization. Thank you.”
    ¶ 18   Consequently, CO2 commenced the underlying district court
    litigation against Montezuma County, asserting claims for
    (1) violation of its members’ civil rights, under 
    42 U.S.C. § 1983
    ;
    and (2) an injunction requiring Montezuma County to calculate and
    9
    refund its members’ alleged overpayment of taxes and precluding
    Montezuma County from levying retroactive taxes against its
    members without delivering actual notice to each member. The
    thrust of CO2’s complaint was that Montezuma County had denied
    its members due process of law by retroactively increasing their
    taxes without providing them individual notice of and an
    opportunity to challenge the retroactive assessment or the
    opportunity to seek a tax abatement.
    ¶ 19   Montezuma County filed a motion to dismiss, arguing, among
    other things, that CO2 was not the real party in interest and that it
    lacked standing.4 The district court granted the motion.
    ¶ 20   On appeal, CO2 contends that the district court erred by
    (1) dismissing its complaint for lack of standing; (2) concluding that
    it was not the real party in interest; and (3) denying its post-
    dismissal motion to amend the complaint. Because we conclude
    that CO2’s members have standing to bring the asserted claims, we
    4Montezuma County also argued that the complaint should be
    dismissed on the basis of claim and issue preclusion because
    Kinder Morgan made the same substantive argument when it
    challenged the retroactive assessment as CO2 makes now. The
    district court denied the motion to dismiss on these bases.
    10
    reverse the court’s order dismissing the complaint and remand for
    further proceedings.
    II.   Standing
    ¶ 21   CO2 contends that the district court erred in dismissing its
    complaint for lack of standing by concluding that (1) CO2’s
    members were not entitled to due process related to the retroactive
    assessment proceedings; and (2) CO2’s members “were not real
    parties in interest with standing” and, thus, CO2 was “not a real
    party in interest [with] standing” to maintain this lawsuit against
    Montezuma County. We agree.
    A.    Standard of Review and Applicable Law
    ¶ 22   For a court to have jurisdiction over a dispute, the plaintiff
    must have standing to bring the case. Ainscough v. Owens, 
    90 P.3d 851
    , 855 (Colo. 2004). Standing is a threshold issue that must be
    satisfied for a court to decide a case on the merits. Barber v. Ritter,
    
    196 P.3d 238
    , 245 (Colo. 2008).
    ¶ 23   Whether a party has standing is a question of law that we
    review de novo. 
    Id.
     And when deciding whether a party has
    standing, we must accept as true all averments of material fact in a
    complaint. Jones v. Samora, 
    2016 COA 191
    , ¶ 21 (citing State Bd.
    11
    for Cmty. Colls. & Occupational Educ. v. Olson, 
    687 P.2d 429
    , 434
    (Colo. 1984)).
    ¶ 24   In Colorado, plaintiffs benefit from a relatively broad definition
    of standing. Ainscough, 90 P.3d at 855. To establish standing, a
    plaintiff must have (1) suffered injury in fact (2) to a legally
    protected interest. Id. (citing Wimberly v. Ettenberg, 
    194 Colo. 163
    ,
    168, 
    570 P.2d 535
    , 539 (1977)).
    ¶ 25   “Injury in fact exists if ‘the action complained of has caused or
    has threatened to cause injury.’” Kreft v. Adolph Coors Co., 
    170 P.3d 854
    , 857 (Colo. App. 2007) (quoting Romer v. Colo. Gen.
    Assembly, 
    810 P.2d 215
    , 218 (Colo. 1991)). An injury in fact may
    be tangible, such as physical damage or economic harm, or
    intangible, such as aesthetic issues or the deprivation of civil
    liberties. Ainscough, 90 P.3d at 856. A remote possibility of future
    injury or an injury that is overly indirect or incidental is
    insufficient. Barber, 196 P.3d at 246.
    ¶ 26   If the plaintiff establishes an injury in fact, “the court must
    then determine whether this injury is to a legal interest which
    entitles the plaintiff to judicial redress.” Olson, 687 P.2d at 435.
    “Resolution of this second prong of standing basically rests on a
    12
    normative judgment that the injury is or is not actionable.” Id. The
    question is whether the plaintiff has a claim for relief under the
    constitution, the common law, a statute, or a rule or
    regulation. Ainscough, 90 P.3d at 856; see also Kreft, 
    170 P.3d at 858
     (“A legally protected interest must emanate ‘from a
    constitutional, statutory, or judicially created rule of law that
    entitles the plaintiff to some form of judicial relief.’” (quoting Bd. of
    Cnty. Comm’rs v. Bowen/Edwards Assocs., Inc., 
    830 P.2d 1045
    ,
    1053 (Colo. 1992))).
    ¶ 27   An organization may have standing to assert claims on behalf
    of its members if it shows that (1) its members would otherwise
    have standing to sue in their own right; (2) the interests it seeks to
    protect are germane to the organization’s purpose; and (3) neither
    the claim asserted nor the relief requested requires the participation
    of individual members in the lawsuit. Jones, ¶ 29.
    B.   Additional Background
    ¶ 28   In its motion to dismiss, Montezuma County argued that CO2
    lacked standing because its members lacked standing, and that its
    members lacked standing because Kinder Morgan, as the Unit
    13
    operator, is the sole entity responsible for paying taxes for the Unit
    and seeking abatement of those taxes.
    ¶ 29   In response, CO2 acknowledged that Kinder Morgan, as the
    Unit operator, was exclusively obligated to submit the annual
    property tax statement and to pay taxes on behalf of all
    nonoperating fractional interest owners in the Unit, but it
    contended that nothing in the governing statutes or guidelines
    authorized Montezuma County “to deal only with the operator when
    a retroactive assessment is in process.” Instead, it argued that
    Montezuma County was required to provide notice to each of its
    members, as taxpayers, and that each member should be able to
    challenge the assessment or to seek an abatement.
    ¶ 30   The district court concluded that CO2 “is not a real party in
    interest and lacks standing to maintain this lawsuit — because the
    members of [CO2] are not real parties in interest with standing to
    bring this suit against Montezuma County.” It concluded that the
    members’ alleged injury was not “to a legally protected or cognizable
    interest” because the statutory scheme governing oil and gas
    taxation “vests all legal and constitutional rights to contest the tax
    14
    assessed and levied with the unit operator” and “require[s]
    Montezuma County to interact only with the unit operator.”
    C.     Analysis
    ¶ 31   To determine whether CO2 has standing as an organization,
    we must first determine whether CO2’s members would have
    standing to sue in their own right. Jones, ¶ 29. Thus, we must
    determine whether CO2 sufficiently alleged that its members
    suffered an injury in fact to a legally protected interest emanating
    from the constitution, a statute, a rule, a regulation, or the common
    law. Kreft, 
    170 P.3d at 858
    .
    1.        Injury in Fact
    ¶ 32   To satisfy the actual injury requirement for standing, CO2
    must demonstrate that the challenged action caused or threatened
    to cause actual injury to its members. Kreft, 
    170 P.3d at 858
    .
    ¶ 33   In its complaint, CO2 alleged that Montezuma County violated
    its members’ due process rights, guaranteed by the Fifth and
    Fourteenth Amendments, by retroactively increasing the assessed
    value of their property without providing the members notice and
    an opportunity to challenge the assessment. It further alleged that
    15
    its members actually paid increased taxes as a result of the
    retroactive assessment.
    ¶ 34   We agree with the district court that CO2 sufficiently alleged
    that its members suffered an injury in fact — both the denial of due
    process and an economic loss. See Morgan v. McCotter, 
    365 F.3d 882
    , 888-89 (10th Cir. 2004) (where due process protections would
    have alleviated harm, the plaintiff has alleged an injury in fact
    (citing Rector v. City & Cnty. of Denver, 
    348 F.3d 935
    , 943-44 (10th
    Cir. 2003))); Hughey v. Jefferson Cnty. Bd. of Comm’rs, 
    921 P.2d 76
    ,
    78 (Colo. App. 1996) (Allegations that plaintiff paid taxes assessed
    on property “supply sufficient evidence of an economic injury to
    satisfy the requirement for an injury in fact.”).
    2.    Legally Protected Interest
    ¶ 35   To satisfy the second criterion for standing, CO2 must
    demonstrate that the injury allegedly suffered by its members is to
    a legally protected interest. Ainscough, 90 P.3d at 856.
    ¶ 36   “Generally, the one who bears the financial burden of a tax is
    a party aggrieved and thus has standing to challenge an
    assessment.” Hughey, 
    921 P.2d at 78
    . But here, the district court
    concluded that “the statutory scheme promulgated vests all legal
    16
    and constitutional rights to contest the tax assessed and levied with
    the unit operator” and that the “Colorado legislature does not grant
    the non-operating interest owners any right or recourse to request
    an audit or to contest the tax levied by the county.”
    ¶ 37   To resolve this issue, we must look to the Colorado statutes
    and guidelines governing the assessment and taxation of oil and gas
    leaseholds and land and determine whether CO2’s members have
    the right to notice and an opportunity to challenge the retroactive
    assessment or to seek an abatement of the increased tax. We
    conclude that each nonoperating fractional interest owner who pays
    taxes is entitled to the panoply of rights afforded a “property
    owner,” “person,” or “taxpayer” under the review, audit, protest,
    abatement, and appeal procedures detailed in the statutes and
    guidelines. Thus, we conclude that the injury allegedly suffered by
    CO2’s members is to a legally protected interest.
    a.    Rules of Statutory Interpretation
    ¶ 38   We review questions of statutory interpretation de novo. Traer
    Creek-EXWMT LLC v. Eagle Cnty. Bd. of Equalization, 
    2017 COA 16
    ,
    ¶ 8. Our primary goals in interpreting a statute are to discern and
    give effect to the General Assembly’s intent. Id. at ¶ 9. When
    17
    construing an administrative regulation, we apply the same rules of
    construction that we would when interpreting a statute. Williams v.
    Colo. Dep’t of Corr., 
    926 P.2d 110
    , 112 (Colo. App. 1996).
    ¶ 39   We first look to the ordinary and common meaning of the
    language used, giving effect to every word whenever possible.
    Cendant Corp. & Subsidiaries v. Dep’t of Revenue, 
    226 P.3d 1102
    ,
    1106 (Colo. 2009). We read words and phrases in context and
    construe them according to the rules of grammar and common
    usage. § 2-4-101, C.R.S. 2020; Gagne v. Gagne, 
    2014 COA 127
    ,
    ¶ 25. And we read and consider the statutory and regulatory
    scheme as a whole, giving consistent, harmonious, and sensible
    effect to all its parts. Cendant Corp., 
    226 P.3d at 1106
    .
    b.     Oil and Gas Property Taxation Law
    i.    Valuing Oil and Gas Leaseholds
    ¶ 40   To ensure uniform taxation premised on uniform assessment
    of property values, the General Assembly enacted article 7 of title
    39, which governs the valuation of oil and gas leaseholds and lands
    18
    for the purpose of property taxation.5 Yuma Cnty. Bd. of
    Equalization v. Cabot Petroleum Corp., 
    856 P.2d 844
    , 848 (Colo.
    1993); see also § 39-3-103(2), C.R.S. 2020. The General Assembly
    also delegated certain authority to the Property Tax Administrator
    as the head of the Division of Property Taxation in the Department
    of Local Affairs. See §§ 39-2-101, -109, C.R.S. 2020.
    ¶ 41   As relevant here, the Property Tax Administrator has the
    authority to prepare and publish manuals, appraisal procedures,
    and instructions concerning methods of appraising and valuing
    land, and to prepare and publish guidelines concerning the audit
    and compliance review of oil and gas leasehold properties for
    property tax purposes. § 39-2-109(1)(e), (k). To this end, the
    Property Tax Administrator prepares and publishes the ARL, a
    series of manuals addressing Colorado property assessment. See 2
    ARL Preface, at ii; 3 ARL Preface, at ii. The manuals, procedures,
    instructions, and guidelines published by the Property Tax
    Administrator must be used by assessors in valuing taxable
    5 For real property classification, “oil and gas leaseholds and lands
    includes all drilled wells producing any kind of petroleum or natural
    gas product, such as oil, gas, or helium and carbon dioxide.” 3 ARL
    at 6.21.
    19
    property. § 39-2-109(1)(e), (k); Huddleston v. Grand Cnty. Bd. of
    Equalization, 
    913 P.2d 15
    , 17 (Colo. 1996) (“[T]he manuals are
    binding on the county assessors.”).
    ¶ 42      Under this statutory and regulatory scheme, oil and gas
    leaseholds and lands are valued based on the selling price of the oil
    or gas “at the wellhead” during the preceding calendar year. §§ 39-
    7-101(1)(d), -102(1)(a). The “selling price at the wellhead” means
    the “net taxable revenues realized by the taxpayer for sale of the oil
    or gas, whether such sale occurs at the wellhead or after gathering,
    transportation, manufacturing, and processing of the product.”
    § 39-7-101(1)(d); see also 3 ARL at 6.25. And “net taxable
    revenues” are “equal to the gross lease revenues, minus deductions
    for gathering, transportation, manufacturing, and processing costs
    borne by the taxpayer pursuant to guidelines established by the
    [Property Tax Administrator].” § 39-7-101(1)(d); see also 3 ARL at
    6.25. The guidelines regarding what may be deducted from gross
    lease revenues are set forth in the ARL. See, e.g., 3 ARL at 6.35-
    6.47.
    20
    ii.   Annual Property Tax Statement
    ¶ 43   Every operator of any producing oil or gas unit must file an
    annual property tax statement for the unit by April 15 of each year.6
    § 39-7-101(1)(d); § 39-7-102(1)(a), C.R.S. 2020; 3 ARL at 6.25; see
    also 3 ARL at 6.21 (specifying that the statement required to be filed
    by April 15 of each year is an “Oil and Gas Real and Personal
    Property Declaration Schedule”). The annual statement or
    declaration schedule must include, among other things,
    (a) The wellhead location thereof and the name
    thereof, if there is a name;
    (b) The name, address, and fractional interest
    of the operator thereof;
    (c) . . . [T]he quantity of gas measured in
    thousands of cubic feet, sold or transported
    from the wellhead during the calendar year
    immediately preceding . . . ;
    (d) The selling price at the wellhead . . . [; and]
    (e) The name, address, and fractional interest
    of each interest owner taking production in
    kind and the proportionate share of total unit
    revenue attributable to each interest owner
    who is taking production in kind[.]
    6 If there is no operator, every person owning any producing oil or
    gas leasehold or lands is required to file the annual statement.
    § 39-7-101(1), C.R.S. 2020.
    21
    § 39-7-101(1); see also 3 ARL at 6.21.7
    iii.   Assessor Valuation
    ¶ 44   Based on the annual statement filed by the operator, rather
    than on its own independent verification of the volume and value of
    the oil and gas produced, the county assessor determines the value
    of the leaseholds and lands in the unit for assessment. § 39-7-
    102(1)(a); KM II, ¶ 30 (“[T]he assessor relies on information that is
    self-reported by the operator, typically without the means to
    independently verify the volume and value of oil and gas produced
    at the leasehold.”).
    ¶ 45   “[F]or taxable personal property on oil and gas leaseholds or
    lands for which the operator has filed the statement required by
    section 39-7-101(1),” the assessor must send a notice of valuation
    7 By March 15 of each year, each nonoperating interest owner may
    submit to the operator a report of the actual net taxable revenues
    received at the wellhead by such owner for production taken in
    kind. § 39-7-101(1.5). If the nonoperating interest owner timely
    submits this information, the operator must use it to determine the
    selling price at the wellhead to be reported in the annual statement.
    Id. But, if the nonoperating interest owner does not timely submit
    this information, “the amount of tax for which such nonreporting,
    nonoperating interest owner is liable shall be calculated based on
    the selling price at the wellhead reported by the operator.” Id.; see
    also 3 ARL at 6.22-6.23.
    22
    of the property “only to the operator, who shall accept it.” § 39-5-
    121(1.5)(b), C.R.S. 2020; see also § 39-7-102.5, C.R.S. 2020
    (indicating that oil and gas leaseholds and lands valued pursuant to
    article 7 follow the schedule for personal property regarding notices
    of valuation and appeals of valuation). Even though the operator is
    obligated to accept the notice of valuation, that acceptance “shall
    not be construed as an indication that the operator agrees with the
    amount of the actual value of the property stated in the notice or as
    obligating the operator to pay the tax attributable to property in
    which the operator has no ownership.” § 39-5-121(1.5)(b).
    iv.   Protest and Appeal of Valuation
    ¶ 46   Pursuant to section 39-5-122(2), “[i]f any person is of the
    opinion that [their] property has been valued too high” by the
    assessor, they may file a written “letter of objection and protest”
    with the assessor’s office and be heard. If the protest is denied, the
    assessor must mail a notice of determination to the “person
    presenting the objection and protest so denied,” stating the reasons
    for declining to change the valuation. § 39-5-122(2); see also 2 ARL
    23
    at 5.3.8 Any person whose objection and protest has been denied
    may appeal to the county board of equalization. § 39-5-122(3); see
    also § 39-8-106(1), (3); 2 ARL at 5.3. If the board of equalization
    denies the petition, the petitioner may appeal. See §§ 39-8-108(1)-
    (3), -107(1), C.R.S. 2020; see also § 24-4-106(9), (11), C.R.S. 2020;
    2 ARL at 5.6.
    v.    Payment of Taxes on Fractional Interests in Lands
    ¶ 47   When oil and gas wells are owned by multiple owners and
    operated as a unit, “the owner of each fractional interest in such
    units shall be liable for the same proportion of the tax levied against
    the total unit that his net taxable revenues received therefrom bears
    to the total net taxable revenues received from such unit.” § 39-10-
    106(1). Once taxes are levied, the unit operator is obligated to
    collect a proportionate share from each fractional interest owner
    8Although ARL Volume 3 is the manual specific to land valuation, it
    provides that “[v]aluation and/or assessment issues not pertaining
    directly to the valuation of land may be referenced to one of the
    other ARL manuals, as appropriate.” 3 ARL Preface, at ii. The
    mechanisms for protesting an assessment or seeking an abatement
    of a levied tax are general valuation and/or assessment issues,
    which are addressed in ARL Volume 2.
    24
    and remit the tax levied against the entire unit to the treasurer of
    the county in which the unit is located. § 39-10-106(2).
    ¶ 48   If the unit operator collects tax from the fractional interest
    owner as provided by statute, but fails to remit the amounts
    collected, it becomes liable for such tax, and the fractional interest
    owner “shall not be subject to any collection and enforcement
    remedies” for such tax. § 39-10-106(2), (4)(b)(III). Failure of the
    unit operator to collect tax from the fractional interest owner,
    however, does not preclude the treasurer from employing “lawful
    collection and enforcement remedies and procedures against the
    owner of any fractional interest to collect the tax owed by such
    owner.” § 39-10-106(4)(a).
    vi.   Abatement of Taxes Levied
    ¶ 49   Within two years after taxes are levied, a taxpayer may file a
    petition with the board of county commissioners to request an
    abatement of taxes due or a refund of taxes paid. 2 ARL at 5.12;
    see also §§ 39-1-113, 39-10-114, C.R.S. 2020. If the petition for
    abatement is denied, the petitioner may appeal. See § 39-10-
    114.5(1), C.R.S. 2020; see also § 24-4-106(11); 2 ARL at 5.14.
    25
    vii.   Audit and Post-Audit Procedures
    ¶ 50   Two statutory provisions authorize an assessor to retroactively
    assess taxes on “omitted property”: sections 39-5-125(1) and 39-10-
    101(2)(a)(I), C.R.S. 2020. KM II, ¶ 25. The question before the
    Colorado Supreme Court in KM II was whether underreporting of
    the value of oil and gas produced at a leasehold constitutes
    “omitted property” subject to corrective assessment under these two
    provisions. Id. It concluded that “the statutory scheme governing
    property taxation of oil and gas leaseholds and lands authorizes the
    retroactive assessment of property taxes when an operator
    underreports the volume or selling price of the oil and gas it
    produces.” Id. at ¶ 34.
    ¶ 51   To this end, the ARL authorizes assessors to conduct reviews
    or audits of “taxpayer oil and gas declarations” and request
    additional information related to the wells owned or operated by
    “the taxpayer.” 3 ARL at 6.52. It also authorizes counties to
    establish reasonable audit procedures “to fairly and accurately
    determine the actual value of oil and gas leaseholds and lands.” 3
    ARL at 6.55. And it specifies what procedures a county’s audit
    program must include and what rights a county must provide to “all
    26
    taxpayers” subject to an audit. 3 ARL at 6.56; see also 2 ARL at
    9.79-9.82.
    c.   The Injury CO2 Alleged Is to a Legally Protected Interest
    ¶ 52    The General Assembly has established a unique representative
    structure under which the unit operator is responsible for reporting
    and paying property taxes levied against oil and gas leaseholds and
    lands that are operated as a unit. But it has not expressly provided
    a similar representative structure for protesting and appealing a
    retroactive assessment or for petitioning for abatement of an
    increased tax liability.
    ¶ 53    As set forth below, notwithstanding the fact that the operator
    is obligated to report, collect, and remit taxes for the unit, the
    nonoperating fractional interest owner remains liable for and must
    pay its proportionate share of the taxes. And the governing statutes
    and ARL vest audit, protest, abatement, and appeal rights in a
    “taxpayer,” “property owner,” and “person,” terms that include a
    nonoperating fractional interest owner who pays taxes. In the
    absence of clear statutory language vesting all such rights in the
    unit operator, we must conclude that nonoperating fractional
    27
    interest owners who pay taxes maintain such rights and have
    standing to sue to enforce them.
    ¶ 54   When oil and gas wells are operated as a unit, the operator
    alone is obligated to file an annual property tax statement for the
    unit. § 39-7-101; 3 ARL at 6.21 (the property tax statement is also
    called a declaration schedule or an oil and gas declaration under
    the ARL). Based on that annual statement, the county assessor
    determines the value of the oil and gas leaseholds and lands in the
    unit and issues a notice of valuation. §§ 39-7-102(1)(a), -102.5;
    § 39-5-121(1.5).
    ¶ 55   Typically, the assessor is required to mail the notice of
    valuation to “each person who owns land.” § 39-5-121(1)(a)(I). But
    the parties appear to agree (so we will assume without deciding it is
    so) that the legislature has relieved assessors of the obligation to
    provide a notice of valuation to each nonoperating fractional
    interest owner in a unit by specifying that the assessor must
    28
    provide the notice of valuation “only to the operator, who shall
    accept it.” § 39-5-121(1.5)(b).9
    ¶ 56   By accepting the notice of valuation, however, the operator
    does not acquiesce to the valuation or otherwise become liable for
    any tax attributable to property owned by others. Id. That is
    because, even though taxes are levied against the “total unit,” each
    fractional interest owner in the unit is liable for its proportionate
    share of the taxes. § 39-10-106(1).
    9 The parties assert that section 39-5-121(1.5)(b), C.R.S. 2020,
    authorizes an assessor to issue an initial notice of real property
    valuation for all the oil and gas leaseholds and lands in a unit only
    to the unit operator. We are not so sure. That section provides, in
    relevant part, that “for taxable personal property on oil and gas
    leaseholds or lands” for which the operator has filed an annual
    statement, “the assessor shall send the notice of valuation only to
    the operator.” Id. (emphasis added). Both real and personal
    property on oil and gas leaseholds and lands are taxed. See §§ 39-
    1-104, 39-7-102, C.R.S. 2020. And although real property
    assessments for oil and gas leaseholds and lands “shall follow the
    schedule for personal property . . . regarding notices of valuation,”
    § 39-7-102.5, C.R.S. 2020 (emphasis added), we see nothing in the
    statutes requiring that real property assessments follow the same
    procedure as personal property assessments. Further, the ARL
    specifies that different notices of valuation are to be used for
    “reporting oil and gas production” and for reporting “[p]ersonal
    property used in the production of oil and gas.” 2 ARL at 9.55.
    However, because neither party raised this concern, and because it
    does not affect our disposition, we assume without deciding that
    the parties are correct, and that the assessor is authorized to send
    an initial notice of real property valuation only to the unit operator.
    29
    ¶ 57   Similarly, although the unit operator is obligated to collect
    taxes from the nonoperating fractional interest owners and to remit
    to the treasurer the full amount of the tax levied against the unit,
    the operator’s failure to collect a proportionate share of the tax from
    the nonoperating fractional interest owner does not preclude the
    treasurer from pursuing collection remedies against that owner to
    collect the tax. § 39-10-106(1), (4)(a); see also § 39-7-108, C.R.S.
    2020.
    ¶ 58   Thus, although the operator alone is obligated to report,
    collect, and remit taxes for the unit, the nonoperating fractional
    interest owner is ultimately liable for and must pay its
    proportionate share of the taxes levied against the unit.
    ¶ 59   The retroactive tax liability in this case arose after an audit.
    The governing statutes do not provide specific audit procedures;
    instead, they authorize the Property Tax Administrator to prepare
    and publish audit guidelines that bind county assessors. § 39-2-
    109(1)(k); Huddleston, 913 P.2d at 17. Thus, the ARL provides the
    audit procedures applicable to Montezuma County’s audit of the
    2008 tax statement filed by Kinder Morgan.
    30
    ¶ 60   Under the ARL, the assessor is required to provide a letter to
    “the taxpayer” indicating that an audit of “that taxpayer’s oil and
    gas declaration” will soon commence. See 3 ARL at 6.55. Upon
    completion of the audit, the county must mail its preliminary audit
    findings to “the taxpayer at the address recorded on the annual
    declaration,” and give “the taxpayer” thirty days to provide
    additional information. Id. at 6.56.
    ¶ 61   Notably, the nonoperating fractional interest owners’ names
    and addresses must be included in the annual tax statement. § 39-
    7-101(1)(e). So, the assessor should have access to each fractional
    interest owner’s address based on the annual statement to provide
    that owner with the letter and preliminary audit findings required
    by the ARL audit procedures.
    ¶ 62   If, as a result of the audit, a change in valuation is
    determined, the county must issue a special notice of valuation. 3
    ARL at 6.56. In contrast to section 39-5-121(1.5)(b), the ARL does
    not specify to whom the special notice of valuation must be sent.
    But the ARL requires the county to provide certain rights to “all
    taxpayers” subject to an audit — including the right to protest the
    indicated value within thirty days — which rights could not be
    31
    exercised if the taxpayer did not receive the special notice of
    valuation from the county. See 3 ARL at 6.56.
    ¶ 63   The county must include with each special notice of valuation
    a special protest form to be completed by “the property owner” to
    initiate a protest of the valuation of the property. 2 ARL at 9.55.
    The “specific requirements” set forth in the ARL for the special
    protest form indicate that “[p]ursuant to §§ 39-5-121(1) and 39-5-
    122(2), C.R.S., every [special notice of valuation] must be sent along
    with a form that, if completed by the property owner, allows the
    property owner to explain the basis for the protest of the property’s
    valuation or classification.” 2 ARL at 9.70.
    ¶ 64   Indeed, the ARL plainly states: “The Division recommends that
    assessors require letters of agency from persons who are not the
    owner of record but are filing a protest on behalf of the property
    owner. The owner is the only person recognized by law to have
    ‘standing’ to file a protest.” 2 ARL at 5.2. And the Property Tax
    Administrator’s “interpretations of the taxation statutes as
    embodied in the ARL are entitled to judicial deference.” Manor Vail
    Condo. Ass’n v. Bd. of Equalization, 
    956 P.2d 654
    , 659 (Colo. App.
    1998).
    32
    ¶ 65   Under section 39-5-122(2), to which the special protest form
    refers, any “person” who believes their property “has been valued
    too high” has the right to object and protest an assessment.
    “Person” means “natural persons, corporations, partnerships,
    limited liability companies, associations, and other legal entities
    which are or may become taxpayers by reason of the ownership of
    taxable real or personal property.” § 39-1-102(9); see also 2 ARL at
    5.1 (“If a taxpayer disagrees with the value assigned by the
    assessor, the taxpayer may file a protest during the statutory
    protest period.”).
    ¶ 66   If a taxpayer files a protest, the county must issue a special
    notice of determination, which must include a written explanation
    “regarding the basis for the omitted property and the county’s
    decision” and an advisement of the taxpayer’s right to file an
    abatement petition. 3 ARL at 6.56. Again citing section 39-5-
    122(2), the ARL requires that the special notice of determination be
    mailed to “each property owner who filed a protest with the
    [a]ssessor.” 2 ARL at 9.79.
    ¶ 67   The special notice of determination itself advises the recipient
    of the right to “continue your appeal” by filing a petition for
    33
    abatement with the county. 2 ARL at 9.82. It then refers to
    sections 39-1-113 and 39-10-114 and advises the recipient of the
    right to appeal any unsatisfactory decision of the board of county
    commissioners to the board of assessment appeals. Id. Under the
    statutes and the ARL, the “taxpayer” is the one vested with the right
    to file a petition for abatement. See § 39-1-113; 2 ARL at 5.13-5.14.
    Again, the ARL confirms: “As with taxpayers filing protests, a
    taxpayer must have proper standing to file an abatement petition.
    The first criterion is ownership.” 2 ARL at 5.15.
    ¶ 68   “Taxpayer” is not defined in the ARL, but its plain meaning
    and dictionary definition is “[s]omeone who pays or is subject to a
    tax.” Black’s Law Dictionary (11th ed. 2019); accord Merriam-
    Webster Dictionary, https://perma.cc/D429-STMG (defining
    “taxpayer” as “one that pays or is liable for a tax”); see also People v.
    Allman, 
    2019 CO 78
    , ¶ 15 (“Because the statute does not
    specifically define the word . . . , we look to the plain and ordinary
    meaning of the word, aided by the dictionary definition.”).
    ¶ 69   Thus, based on the plain language of the statutes and the ARL
    — which we are required to interpret together, to give consistent,
    harmonious, and sensible effect to all the provisions, see Cendant
    34
    Corp., 
    226 P.3d at
    1106 — we conclude that each nonoperating
    fractional interest owner who pays taxes is a “property owner,” a
    “person,” and a “taxpayer” entitled to the panoply of rights afforded
    such “property owner,” “person,” or “taxpayer” under the review,
    audit, protest, abatement, and appeal procedures detailed in the
    ARL and related statutes. See 3 ARL at 6.52-6.56.
    ¶ 70   Nothing in the statutes or the ARL indicates that a unit
    operator is the only “property owner” to whom a special notice of
    valuation and special protest form need be sent, see 2 ARL at 9.55,
    9.70, 9.79, or who has standing to file a protest, see 2 ARL at 5.2.
    Nothing in the statutes or the ARL indicates that a unit operator is
    the only “person” who may protest the valuation of the leaseholds
    and lands in an oil and gas unit as reflected in a notice of valuation
    or special notice of valuation. See § 39-5-122(2). Nothing in the
    statutes or the ARL indicates that a unit operator is the only
    “taxpayer” who is entitled to be notified of an audit, receive
    preliminary audit findings from the assessor, or protest the
    assessment, see 3 ARL at 6.56, or who has standing to file a
    petition for abatement of taxes levied against the unit, see § 39-1-
    113; 2 ARL at 5.13-5.15. Nothing in the statutes or ARL vests these
    35
    rights exclusively in the unit operator or appoints the unit operator
    as the statutory agent or representative of all nonoperating
    fractional interest owners when oil and gas wells are operated as a
    unit. And nothing in the ARL audit guidelines mandates a different
    procedure when the property is retroactively assessed or when taxes
    are increased retroactively.
    ¶ 71   We acknowledge that our holding today may upset settled
    practices regarding how counties review, audit, and retroactively
    assess the value of oil and gas leaseholds and lands and how they
    handle protests and petitions for abatement resulting from such
    retroactive assessments. It may also contravene the expectations of
    many nonoperating fractional interest owners, who may presume
    that the unit operator will handle such matters on their behalf. To
    be sure, this may be a case of “be careful what you wish for”
    because if an individual nonoperating fractional interest owner is
    entitled to receive notice of and challenge the retroactive assessment
    of its property, then it is equally obligated to raise such a challenge
    on its own behalf or designate an agent to protest for it. See 2 ARL
    at 5.2.
    36
    ¶ 72   But our primary objective when interpreting the governing
    statutes and the ARL is to effectuate the General Assembly’s intent
    “by looking to the plain meaning of the language used, considered
    within the context of the statute as a whole.” Hogan v. Bd. of Cnty.
    Comm’rs, 
    2018 COA 86
    , ¶ 11 (citation omitted), aff’d sub nom. Mook
    v. Bd. of Cnty. Comm’rs, 
    2020 CO 12
    . We cannot insert words into
    a statute. See id. at ¶ 23 (declining to “judicially rewrite” statutes to
    support government’s interpretation of term in ARL) (citation
    omitted). Absent clear language authorizing the unit operator to
    represent all tax-paying nonoperating fractional interest owners in
    the review, audit, protest, and abatement procedures, each such
    taxpayer has standing to assert that its rights in such procedures
    have been violated.
    ¶ 73   CO2 alleged that its members have suffered an injury in fact
    — the deprivation of due process and an economic loss — to a
    legally cognizable interest as contemplated by statutory and
    constitutional provisions. Thus, we conclude that CO2’s members
    have standing to bring the claims asserted in the complaint against
    Montezuma County.
    37
    ¶ 74   This conclusion, however, does not end the inquiry because
    CO2 must also have organizational standing to bring the asserted
    claims on behalf of its members. Jones, ¶ 29. We have already
    concluded that CO2’s members would have standing to sue in their
    own right. But for CO2 to have organizational standing, the
    interests it seeks to protect must be germane to the organization’s
    purpose and the claims asserted and the relief requested must not
    require participation by individual members in the lawsuit. Id.
    ¶ 75   Because the district court determined that CO2’s members
    lacked standing in their own right, it did not determine whether
    CO2 met the remaining criteria to have organizational standing.
    Neither party has argued that we should determine this question for
    the first time on appeal. Accordingly, the district court must
    address this issue on remand.
    ¶ 76   In reaching our conclusion today, we express no opinion as to
    the merits of CO2’s arguments. The district court disposed of this
    case on standing. Standing is a threshold issue separate from
    resolution of the merits. Barber, 196 P.3d at 245. We have
    concluded that CO2’s members have standing. Thus, we remand to
    the district court for further proceedings.
    38
    III.   Real Party in Interest
    ¶ 77   CO2 contends on appeal that the district court erred by
    concluding it was not “the real party in interest” with standing to
    maintain the action. But the court’s order in this regard appears to
    contradict itself. The court first concluded that CO2 was the real
    party in interest under C.R.C.P. 17(a), finding that CO2 was “a
    party with whom or in whose name a contract has been made for
    the benefit of another.” But then, as part of its standing analysis,
    the court found that CO2 “is not a real party in interest and lacks
    standing to maintain this lawsuit.”
    ¶ 78   Colorado Rule of Civil Procedure 17(a) provides that “[e]very
    action shall be prosecuted in the name of the real party in interest.”
    The purpose of the rule is “to protect defendants from the
    harassment of lawsuits by persons who do not have the power or
    right to make final and binding decisions concerning prosecution,
    compromise, and settlement.” Williams v. Genesee Dev. Co. No. 2,
    
    759 P.2d 823
    , 825 (Colo. App. 1988). “The real party in interest is
    that party who, by virtue of substantive law, has the right to invoke
    the aid of the court in order to vindicate the legal interest in
    question.” Goodwin v. Dist. Ct., 
    779 P.2d 837
    , 843 (Colo. 1989).
    39
    ¶ 79   The concepts of “real party in interest” and “standing” are
    often confused. 5A Stephen A. Hess, Colorado Practice Series:
    Handbook On Civil Litigation § 4:2, Westlaw (2020 ed. database
    updated Oct. 2020). “The distinctions between these categories are
    not always clear, and sometimes the inquiries overlap.” Id. Our
    courts have, on occasion, analyzed standing and real party in
    interest together. See, e.g., Miller v. Accelerated Bureau of
    Collections, Inc., 
    932 P.2d 824
    , 825 (Colo. App. 1996); Summers v.
    Perkins, 
    81 P.3d 1141
    , 1142 (Colo. App. 2003).
    ¶ 80   Standing “is the broadest and most substantive idea, which
    insures that plaintiffs assert only those claims demonstrating a
    legally cognizable injury so that the jurisdiction of the courts is
    exercised only when an actual controversy exists.” Hess, § 4.2.
    When the real party in interest is in issue, however, “there is
    usually no question about whether a legally cognizable claim has
    been stated. Instead, the question is to determine who possesses
    the right to assert the claim . . . .” Id. Thus, even if a plaintiff has
    standing to bring a claim, they may not be the real party in interest
    if, for example, they have assigned that claim to a third party. See
    40
    Platte Valley Mortg. Corp. v. Bickett, 
    916 P.2d 631
    , 633 (Colo. App.
    1996) (“An assignee of a claim is a real party in interest.”).
    ¶ 81   We have already concluded, as part of our standing analysis,
    that CO2’s members have the right to invoke the aid of the court to
    vindicate their rights under the constitution, statutes, and ARL
    guidelines. CO2’s members are real parties in interest. But CO2’s
    members are not the plaintiffs; CO2 is the plaintiff.
    ¶ 82   Rule 17(a) provides that “a party with whom or in whose name
    a contract has been made for the benefit of another . . . may sue in
    his own name without joining with him the party for whose benefit
    the action is brought.” The district court found that CO2 was such
    a party. Neither party appeals that finding and we see no reason to
    disturb it.10
    IV.   Attorney Fees
    ¶ 83   CO2 contends that it is entitled to attorney fees pursuant to
    C.A.R. 38(b) and 39.1 because Montezuma County’s defense of the
    district court’s order was frivolous and groundless under section
    10Because of our disposition, we need not address CO2’s remaining
    contention that the district court erred by denying its post-
    dismissal motion to amend its complaint.
    41
    13-17-102(4), C.R.S. 2020. CO2 does not appeal the district court’s
    ruling that the parties are to bear their own attorney fees and costs
    incurred at the trial court level. Instead, it seeks attorney fees for
    Montezuma County’s defense of the district court orders on appeal.
    We conclude that CO2 is not entitled to appellate attorney fees.
    ¶ 84   A court must award attorney fees against a party who
    “brought or defended a civil action, either in whole or in part, that
    the court determines lacked substantial justification.” § 13-17-
    102(2); see also § 13-17-102(4). An action lacks substantial
    justification if it is “substantially frivolous, substantially
    groundless, or substantially vexatious.” § 13-17-102(4); see also
    Castillo v. Koppes-Conway, 
    148 P.3d 289
    , 292 (Colo. App. 2006).
    ¶ 85   An appeal should be considered frivolous only “if the
    proponent can present no rational argument based on the evidence
    or law in support of a proponent’s claim or defense, or the appeal is
    prosecuted for the sole purpose of harassment or delay.” Mission
    Denver Co. v. Pierson, 
    674 P.2d 363
    , 366 (Colo. 1984). And we
    should award attorney fees on appeal as a sanction under C.A.R.
    38(b) only in “clear and unequivocal cases” of “egregious conduct.”
    Wood Bros. Homes, Inc. v. Howard, 
    862 P.2d 925
    , 935 (Colo. 1993).
    42
    ¶ 86   We do not find that Montezuma County’s defense of the
    district court’s order lacks substantial justification. Even though it
    was ultimately unsuccessful, Montezuma County presented rational
    arguments based on the evidence and the law — a particularly
    complicated scaffold of statutes and guidelines — in support of its
    claims. See Mission Denver Co., 674 P.2d at 366 (finding that
    appeal was not frivolous “merely because [it was] ultimately
    unsuccessful). Therefore, we decline to award CO2 its appellate
    attorney fees.
    V.    Conclusion
    ¶ 87   We reverse the district court’s order dismissing the complaint
    for lack of standing and remand for further proceedings consistent
    with this opinion.
    JUDGE ROMÁN and JUDGE WELLING concur.
    43