                   This opinion is subject to revision before final
                        publication in the Pacific Reporter

                                   2019 UT 71


                                    IN THE

        SUPREME COURT OF THE STATE OF UTAH

                              OSCAR CASTRO,
                                Appellant,
                                       v.
                          MARI TERESA LEMUS,
                               Appellee.

                             No. 20180094
                       Heard February 22, 2019
                       Filed December 19, 2019

             On Certification from the Court of Appeals

                       Fourth District, Provo
                   The Honorable Lynn W. Davis
                          No. 174401943

                                Attorneys: 1
 Troy L. Booher, Julie J. Nelson, Michael J. Teter, Salt Lake City,
             Dustin A. Hardy, Orem, for appellant
            Aaron M. Drake, Salt Lake City, for appellee

   JUSTICE PETERSEN authored the opinion of the Court, in which
       CHIEF JUSTICE DURRANT, ASSOCIATE CHIEF JUSTICE LEE,
           JUSTICE HIMONAS, and JUSTICE PEARCE joined.



_____________________________________________________________
   1   Amicus Curiae attorneys are:
    Sean D. Reyes, Att’y Gen., Andrew Dymek, Asst. Att’y Gen.,
Tyler R. Green, Solic. Gen., Stanford E. Purser, Deputy Solic. Gen.,
Salt Lake City, for State of Utah.
                           CASTRO v. LEMUS
                         Opinion of the Court

   JUSTICE PETERSEN, opinion of the Court:

                          INTRODUCTION
    ¶1 Appellant Oscar Castro seeks to establish his paternity of a
child born to Mari Teresa Lemus (Mother), who is married to
another man (Husband). Castro contends that he is the biological
father of the child. But because Mother was married when the child
was born, the Utah Uniform Parentage Act (UUPA) 2 presumes that
her husband is the child’s father. Castro filed a petition in the district
court to rebut this legal presumption. The district court dismissed
Castro’s paternity petition, applying court of appeals’ precedent to
determine that Castro has no standing under the UUPA because the
child was born during a marriage with a presumed father. See
generally R.P. v. K.S.W., 2014 UT App 38, 320 P.3d 1084.
    ¶2 On appeal, Castro argues that the court of appeals’
interpretation of the UUPA is incorrect. Alternatively, he contends
that if the UUPA does deny him standing, it is unconstitutional.
   ¶3 We conclude that section 78B-15-602 of the UUPA grants
standing to Castro and the other persons and entities listed in that
provision and that subsection 607(1) does not revoke that standing
when the child has a presumed father. Accordingly, we reverse and
remand.
                           BACKGROUND 3
    ¶4 Mother married Husband in 2012. Early in the marriage,
Husband traveled to Mexico to visit his mother, who had fallen ill.
Because he was later unable to return to Utah, Mother would travel
to and from Mexico periodically to be with Husband.
   ¶5 Mother and Husband separated two years later, and she
returned to Utah while he remained in Mexico. Soon thereafter,
Mother began dating Castro. Their relationship lasted approximately
two years, during which time they conceived a child.
_____________________________________________________________
   2  The Utah Uniform Parentage Act is set out in Utah Code
sections 78B-15-101 to -902.
   3  “On appeal from a motion to dismiss, we must accept the
factual allegations in the complaint as true and view all reasonable
inferences from them in the light most favorable to the plaintiff.”
Pang v. Int’l Document Servs., 2015 UT 63, ¶ 3, 356 P.3d 1190 (citation
omitted).


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                         Opinion of the Court

    ¶6 But in May 2016, Husband returned to Utah and he
reconciled with Mother. The child was born to Mother in December
that same year. Mother and Husband have remained married and
neither spouse has ever initiated divorce proceedings. Mother and
Husband allege that they have fulfilled all parental roles for the child
since birth, and they desire to continue to do so free from Castro’s
interference.
    ¶7 But Castro wants to establish himself as the child’s legal
father. To do so, Castro filed a petition in the district court to
challenge Husband’s presumed paternity; assert his own parentage;
and establish custody, child support, and parent-time. In response,
Mother filed a rule 12(b)(6) motion to dismiss for failure to state a
claim. Relying on the court of appeals’ decision in R.P. v. K.S.W.,
2014 UT App 38, 320 P.3d 1084, and its progeny, Mother argued that
subsection 78B-15-607(1) of the UUPA denies Castro standing to
challenge the presumption of paternity established under
subsection 204(1)(a).
   ¶8 In his opposition to Mother’s motion to dismiss, Castro
conceded that R.P. v. K.S.W. is binding upon the district court and
limits standing as to who may challenge the presumption of
paternity. But he argued that such a limitation violates his
constitutional rights to procedural and substantive due process and
equal protection.
   ¶9 Following a hearing on the motion to dismiss, the district
court dismissed Castro’s paternity petition. Relying on court of
appeals’ precedent, the district court reiterated that the UUPA
purposefully subordinates the judiciary’s truth-seeking function to
policy concerns about protecting a marriage from third-party
challenges. The court also concluded that Castro had failed to
overcome the presumption that the UUPA is constitutional.
    ¶10 Castro timely appealed from the district court’s final ruling
on the motion to dismiss. The court of appeals certified the case to
this court to review unsettled constitutional questions regarding the
UUPA. We exercise jurisdiction under Utah Code section
78A-3-102(3)(b).
                     STANDARD OF REVIEW
   ¶11 “We review the grant of a motion to dismiss for
correctness, granting no deference to the decision of the district
court.” Hudgens v. Prosper, Inc., 2010 UT 68, ¶ 14, 243 P.3d 1275. A
rule 12(b)(6) motion to dismiss for failure to state a claim should be
granted only if “assuming the truth of the allegations in the

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                          Opinion of the Court

complaint and drawing all reasonable inferences therefrom in the
light most favorable to the plaintiff, it is clear that the plaintiff is not
entitled to relief.” Id. (citation omitted). “The interpretation and
constitutionality of a statute are questions of law that we review for
correctness.” Waite v. Utah Labor Comm’n, 2017 UT 86, ¶ 5, 416 P.3d
635.
                               ANALYSIS
    ¶12 Castro argues that the court of appeals has incorrectly
interpreted the UUPA to deny standing to alleged fathers when the
child is conceived or born during a marriage between the mother
and another man who is legally presumed to be the child’s father. In
the alternative, he argues that if we conclude the UUPA does deny
him standing, the statute is unconstitutional for a number of reasons.
Because we agree with Castro that the UUPA grants standing to
alleged fathers in these circumstances, we do not reach his
constitutional claims.
                  I. STATUTORY INTERPRETATION
    ¶15 The initial question before us is whether the UUPA grants
standing to biological fathers—termed “alleged fathers” 4 in the
statute—when another man is legally presumed to be the child’s
father. Castro argues that the UUPA clearly grants him standing.
Mother argues it clearly does not.
    ¶16 The court of appeals addressed this question in R.P. v.
K.S.W., 2014 UT App 38, 320 P.3d 1084. In R.P., a married woman
conceived a child during an extramarital affair. Id. ¶ 2. After she
informed the alleged father of the pregnancy as well as her intent to
remain married, the alleged father filed a petition to establish
paternity. Id. Initially, the mother admitted that the alleged father
was the child’s biological father, and they entered into a stipulated
agreement regarding child support, parent-time, and joint legal
custody. Id. ¶¶ 2–3. But when the alleged father later requested
increased parent-time, the mother moved to set aside the agreement
and dismiss the case, arguing, among other things, that the alleged
father lacked standing to challenge the child’s paternity. Id. ¶ 3. The

_____________________________________________________________
   4 “‘Alleged father’ means a man who alleges himself to be, or is
alleged to be, the genetic father or a possible genetic father of a child,
but whose paternity has not been determined.” UTAH CODE
§ 78B-15-102(2).


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district court agreed that the alleged father lacked standing and
dismissed the case. Id.
    ¶17 The court of appeals affirmed that ruling. Id. ¶¶ 1, 45. After
analyzing the relevant statutory provisions, it concluded that they
were ambiguous as to who had standing to rebut the presumption of
paternity. Id. ¶¶ 15–17. So the court looked to the UUPA’s legislative
history and policy objectives. Id. ¶¶ 18–26. Ultimately, the court of
appeals concluded the UUPA denied standing to the alleged father
to assert his paternity while the mother’s marriage to the presumed
father remained intact. Id. ¶ 26.
    ¶18 This is a matter of first impression for this court. We
conclude that the UUPA does grant an alleged father standing to
assert his paternity, even where, as here, the child has a presumed
father.
   ¶19 When interpreting a statute, our primary objective “is to
ascertain the intent of the legislature.” Bagley v. Bagley, 2016 UT 48,
¶ 10, 387 P.3d 1000 (citation omitted). Because “[t]he best evidence of
the legislature’s intent is the plain language of the statute itself,” we
analyze that first. Id. (alteration in original) (citation omitted). In
doing so, “[w]e read the plain language of the statute as a whole[]
and interpret its provisions in harmony with other statutes in the
same chapter and related chapters.” Miller v. Weaver, 2003 UT 12,
¶ 17, 66 P.3d 592. Accordingly, we begin by looking at the text of the
UUPA.
    ¶20 The UUPA governs “determinations of parentage in this
state.” UTAH CODE § 78B-15-103(1). “‘Determination of parentage’
means the establishment of the parent-child relationship,” id.
§ 78B-15-102(9), which is “the legal relationship between a child and
a parent of the child,” id. § 78B-15-102(18). The term “[p]arent-child
relationship” includes “the mother-child relationship and the
father-child relationship.” Id. (internal quotation marks omitted).
    ¶21 Establishing the mother-child relationship is usually a
straightforward matter because the mother has given birth to the
child. 5 Id. § 78B-15-201(1)(a)(i) (establishing a mother-child

_____________________________________________________________
   5 We note, however, that the mother-child relationship can also
be established through a gestational agreement, adjudication,
adoption, or an unrebutted presumption of maternity. See id.
§ 75B-15-201(1)(a)(ii)–(v).


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                           Opinion of the Court

relationship by “the woman’s having given birth to the child”). But
because this is not the case for the father, Utah law creates a
presumption that a married mother’s husband is the father of the
child if the child is born during the marriage. See id.
§ 78B-15-204(1)(a). This presumption is rebuttable. A “[p]resumed
father” is defined in the UUPA as “a man who, by operation of law
under [s]ection 78B-15-204, is recognized as the father of a child until
that status is rebutted or confirmed as set forth in this chapter.” Id.
§ 78B-15-102(20) (emphasis added) (internal quotation marks
omitted).
    ¶22 When no presumption of paternity exists, Utah law
recognizes other pathways to establish paternity. Under the UUPA,
the father-child relationship can be established in a number of ways,
including by a legal declaration of paternity (declarant father), an
adjudication of paternity (adjudicated father), or adoption. See id.
§ 78B-15-201(2)(b)–(d).
            A. Section 602—the UUPA’s Standing Provision
   ¶23 The UUPA explicitly identifies the parties with standing to
maintain a proceeding to adjudicate the parentage of a child.
Specifically, Utah Code section 78B-15-602, titled “Standing to
maintain proceeding,” provides:
       Subject to Part 3, Voluntary Declaration of Paternity
       Act, and Sections 78B-15-607 and 78B-15-609, a
       proceeding to adjudicate parentage may be maintained
       by:
          (1) the child;
          (2) the mother of the child;
          (3) a man whose paternity of the child is to be
              adjudicated;
          (4) the support-enforcement agency or other
              governmental agency authorized by other law;
          (5) an authorized adoption agency or licensed
              child-placing agency;
          (6) a representative authorized by law to act for an
              individual who would otherwise be entitled to
              maintain a proceeding but who is deceased,
              incapacitated, or a minor; or
          (7) an intended parent under Part 8, Gestational
              Agreement.

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                         Opinion of the Court

    ¶24 Castro argues section 602 definitively answers the question
before us. This specific standing provision explicitly grants standing
to “a man whose paternity of the child is to be adjudicated.” Id.
§ 78B-15-602(3). An alleged biological father such as Castro arguably
falls within this broad category, and he would therefore have
standing to bring a paternity proceeding under the UUPA.
             B. Section 607—Limitations in Proceedings in
                which the Child has a Presumed Father
    ¶25 If our analysis were to end here, the question of Castro’s
standing would be straightforward. But the UUPA’s standing
provision is expressly “[s]ubject to Part 3, Voluntary Declaration of
Paternity Act, and Sections 78B-15-607 and 78B-15-609.” Id.
§ 78B-15-602. Mother argues that subsection 607(1) takes back some
of the standing that section 602 grants. Subsection 78B-15-607(1)
reads:
       § 78B-15-607.   Limitation—Child      having    presumed
       father
      (1) Paternity of a child conceived or born during a
      marriage with a presumed father, as described in
      Subsection 78B-15-204(1)(a), (b), or (c),[6] may be raised
      by the presumed father, the mother, or a support
_____________________________________________________________
   6 Under Utah Code section 78B-15-204(1), “[a] man is presumed
to be the father of a child if”:
       (a) He and the mother of the child are married to each
       other and the child is born during the marriage;
       (b) He and the mother of the child were married to
       each other and the child is born within 300 days after
       the marriage is terminated by death, annulment,
       declaration of invalidity, or divorce, or after a decree of
       separation; [or]
       (c) Before the birth of the child, he and the mother of
       the child married each other in apparent compliance
       with law, even if the attempted marriage is or could be
       declared invalid, and the child is born during the
       invalid marriage or within 300 days after its
       termination by death, annulment, declaration of
       invalidity, or divorce or after a decree of separation
       ....


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                         Opinion of the Court

       enforcement agency at any time before filing an action
       for divorce or in the pleadings at the time of the
       divorce of the parents.
    ¶26 Mother construes this language to mean that when a child
is “conceived or born during a marriage with a presumed father,”
paternity may be challenged only by the mother, the presumed
father, or a support enforcement agency. In other words, she asserts
that this provision takes away standing from the other persons and
entities listed in section 602 when a presumed father exists (as
described in subsections 204(1)(a), (b), and (c)).
    ¶27 In R.P., the court of appeals concluded that subsection
607(1) was ambiguous. 2014 UT App 38, ¶¶ 15–17. It identified two
possible readings. Id. ¶ 16. Under the first reading, “[A]ll of the
persons listed in section 602 have standing to challenge that child’s
paternity at any time, except the presumed father and the mother,
who may do so only prior to filing an action for divorce or in the
divorce pleadings.” Id. Under the second reading, “[S]ection 607
limits the right to raise the child’s paternity to the two persons listed:
the presumed father and the mother.” 7 Id. In support of this reading,
the court found the language “[p]aternity . . . may be raised by . . . .”
to signal a standing limitation. Id. ¶ 19 (quoting UTAH CODE
§ 78B-15-607(1)). But the court ultimately concluded both readings
were plausible and looked to the UUPA’s legislative history and
policy objectives to break the tie. Id. ¶¶ 18–26. Those sources
persuaded the court to adopt the second interpretation, thus limiting
standing under the UUPA to only the mother and presumed father
when a presumed father exists. Id.
   ¶28 Castro disagrees with the interpretation of subsection
607(1) advanced by Mother and previously adopted by the court of

_____________________________________________________________
   7 In 2017, after R.P. v. K.S.W., 2014 UT App 38, 320 P.3d 1084,
issued, the legislature amended subsection 78B-15-607(1) to also
include “a support enforcement agency” as one of the parties
allowed to challenge a child’s paternity “at any time before filing an
action for divorce or in the pleadings at the time of the divorce of the
parents.” So, in 2014, the court of appeals’ interpretation of
subsection 607(1) limited standing to the mother and presumed
father. See R.P., 2014 UT App 38, ¶ 26. Now, Mother’s similar
interpretation of subsection 607(1) limits standing to the mother,
presumed father, and a support enforcement agency.


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appeals. He argues that section 602 identifies those with standing
under the UUPA, and subsection 607(1) does nothing to alter that.
Instead, he asserts that it merely establishes a deadline to challenge
paternity if a mother and presumed father divorce, which applies
only to the parties whose interests are adjudicated in the divorce
proceeding: the mother, the presumed father, and a support
enforcement agency.
   ¶29 As we outlined above, Castro is correct that section 602 is
the UUPA’s specific standing provision. But because the standing
provision is “[s]ubject to” three other parts of the UUPA, including
section 607, the question presented here is whether subsection 607(1)
operates to modify the standing granted in section 602. 8 We
conclude that it does not.
    ¶30 First, subsection 607(1) never expressly limits standing. The
section is titled “Limitation,” not “Standing Limitation.” And it
contains no clear language limiting standing. It does not say: “If a
child has a presumed father . . . only the mother, the presumed
father, or a support enforcement agency may initiate a proceeding to
adjudicate the parentage of that child.”
    ¶31 In contrast, another section of the UUPA does contain
express language where the legislature intended to limit standing.
Appearing just before the disputed provision, section 606 states that
“[a] proceeding to adjudicate the parentage of a child having no
declarant or adjudicated father may be commenced at any time. If
initiated after the child becomes an adult, only the child may initiate the
proceeding.” (Emphasis added.) This language unequivocally limits
standing to the child once the child becomes an adult. In
comparison, subsection 607(1) contains no such language.
    ¶32 Short of such unequivocal language, subsection 607(1)
might have signaled a standing limitation if the first sentence ended
after “enforcement agency,” to read: “Paternity of a child conceived
or born during a marriage with a presumed father . . . may be raised
by the presumed father, the mother, or a support enforcement
agency.”



_____________________________________________________________
   8 Mother has not argued that either of the other parts of the
UUPA to which section 602 is subject—part 3 and section 609—affect
standing here.


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                          Opinion of the Court

    ¶33 But the sentence does not end there. It goes on to direct
when the three listed parties may raise the issue of paternity.
Specifically, the language states that when a child was conceived or
born during a marriage, and therefore a presumed father exists, the
mother, the presumed father, or a support enforcement agency may
raise paternity “at any time before filing an action for divorce or in
the pleadings at the time of the divorce of the parents.” UTAH CODE
§ 78B-15-607(1). This timing directive becomes the substantive focus
of the provision.
    ¶34 Ultimately, subsection 607(1) is silent as to the other
persons and entities with standing under section 602—it does not set
timing limitations for them, and it also does not speak to their
standing. It simply does not address them at all. We do not read this
silence to revoke the standing expressly granted to the persons and
entities listed in section 602, which specifically addresses standing
under the UUPA. Rather, we read subsection 607(1) to mean only
what it expressly states: that the mother, the presumed father, or a
support enforcement agency may raise the issue of paternity at any
time, but if there is a divorce, they must raise it either before a
divorce petition is filed or in the divorce pleadings. 9

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   9   The court of appeals was concerned that this reading allows
         all other persons identified in section 602 to challenge
         the paternity of a child with a presumed father at any
         time but restrict[s] a challenge by the presumed father
         and the mother to any time prior to the filing of a
         divorce action or in the pleadings at the time of
         divorce.
R.P., 2014 UT App 38, ¶ 24. But for reasons of estoppel and finality,
this timing limitation makes sense. Notably, if the mother and
presumed father do not divorce, the UUPA places no time limit on
them. But if they do divorce, the district court must adjudicate issues
related to any children of the marriage—custody, parent-time, and
child support—as part of that proceeding. The question of paternity
precedes those issues. Subsection 607(1) requires those whose
interests are to be adjudicated in a divorce proceeding to raise the
issue of paternity either up front or never. In practice, this means
that if either parent is dissatisfied with a court order regarding
custody, parent-time, or child support, he or she cannot later
collaterally attack that order by arguing for the first time that the
                                                              (cont’d.)
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    ¶35 Second, looking at subsection 607(1) within the structure of
the statute as a whole, it becomes even clearer that it should be read
as a limitation on timing, not standing. Nearby sections with similar
structures are titled “No limitation” or “Limitation,” and it is
apparent that the word “limitation” refers to timing limitations
within those provisions, not standing limitations.
   ¶36   For example, section 606 states:
      § 78B-15-606. No limitation—Child having no declarant
      or adjudicated father
      A proceeding to adjudicate the parentage of a child
      having no declarant or adjudicated father may be
      commenced at any time. If initiated after the child
      becomes an adult, only the child may initiate the
      proceeding.
(Emphases added.)
    ¶37 The title “No limitation” must refer to timing—specifically
that when a child has no declarant or adjudicated father, there is no
limitation on when a paternity proceeding may be raised. It “may be
commenced at any time.” Id. § 78B-15-606. “No limitation” cannot
refer to standing, which is clearly limited in the second sentence to
the child once he or she becomes an adult.
   ¶38 The other section cross-referenced in           the   standing
provision, section 609(1), states:
      § 78B-15-609. Limitation—Child having declarant father
      (1) If a child has a declarant father, a signatory to the
      declaration of paternity or denial of paternity or a
      support-enforcement agency may commence a proceeding
      seeking to rescind the declaration or denial or
      challenge the paternity of the child only within the time
      allowed under Section 78B-15-306 or 78B-15-307.
(Emphases added.)
_____________________________________________________________
husband is not really the child’s father. While the same estoppel
concerns do not necessarily apply to support enforcement agencies,
such agencies frequently intervene in divorce cases and their
interests are adjudicated in those proceedings. So, the inclusion of
support enforcement agencies in this provision promotes finality and
consistency in divorce decrees.


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                         Opinion of the Court

    ¶39 As in section 606, “[l]imitation” here refers to timing
limitations—specifically, those time limits established in sections
78B-15-306 and -307. Those sections appear in part 3 of chapter 15,10
which deals with voluntary declarations or denials of paternity. See
id. § 78B-15-301, -303. Section 306(1) allows a person to rescind a
declaration or denial of paternity but only within two specified
timeframes. 11 And section 307 provides that if a signatory or a
support enforcement agency misses those deadlines, a proceeding to
challenge the declaration or denial may be commenced “only on the
basis of fraud, duress, or material mistake of fact.” Id.
§ 78B-15-307(1).
    ¶40 Thus, section 609(1) closes a potential loophole by applying
the deadlines set out in subsection 306(1) for rescinding a declaration
or denial of paternity to proceedings under the UUPA that involve a
child with a declarant father. As in subsection 607(1), this makes
sense based on principles of estoppel. If a man has either declared or
denied that he is a child’s father, the UUPA gives him a period of
time in which to rescind his declaration or denial of paternity, but it
restricts his ability to do so after an adjudicative proceeding relating
to the child (to which he is a party) has begun.
    ¶41 Looking now to the subsection at issue here, it is similarly
structured. Section 607’s title refers to a “[l]imitation” for a certain
type of paternity case:
        § 78B-15-607.   Limitation—Child    having    presumed
        father
        (1) Paternity of a child conceived or born during a
        marriage with a presumed father, as described in
        [s]ubsection 78B-15-204(1)(a), (b), or (c), may be raised
        by the presumed father, the mother, or a support

_____________________________________________________________
   10 We note that section 602 is “[s]ubject to Part 3” and sections 607
and 609. As we explain here, part 3 and section 609 are related, in
that section 609 cross-references the deadlines established in part 3 of
this chapter.
   11 Subsection 306(1) permits a signatory to a declaration or denial
of paternity to rescind that declaration or denial within the earlier of
“60 days after the effective date of the declaration or denial,” or “the
date of notice of the first adjudicative proceeding [relating to the
child] to which the signatory is a party.”


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        enforcement agency at any time before filing an action for
        divorce or in the pleadings at the time of the divorce of the
        parents.
(Emphases added.)
   ¶42 When viewed together with sections 606 and 609, in which
“limitation” clearly relates to the time within which the respective
proceedings must be commenced, it becomes apparent that
subsection 607(1) follows the same pattern. It functions like sections
606 and 609 to establish when certain persons with standing may
commence a proceeding in certain types of cases (or, in the case of
section 606, to establish that there are no time limitations). The
common threads running through these time limits appear to be
estoppel and equitable concerns.
    ¶43 Mother observes that when a child has a presumed father,
the UUPA specifies that “[a] presumption of paternity . . . may only
be rebutted in accordance with [s]ection 78B-15-607.” See id.
§ 78B-15-204(2). 12 She argues that this means section 607, rather than
section 602, governs standing in paternity cases involving a
presumed father. She is incorrect.
    ¶44 It is accurate that the UUPA provides that the presumption
of paternity must be rebutted in accordance with section 607. See id.
But this has nothing to do with standing. Section 607 as a whole
directs when and how paternity may be rebutted.
    ¶45 We have focused on subsection 607(1) because its meaning
is the primary point of dispute before us. But section 607 as a whole
is made up of four subsections. As discussed, subsection 607(1) limits
when the mother, the presumed father, and a support enforcement
agency may commence a proceeding in the event of a divorce. It also
establishes other rules applicable only to the mother, the presumed
father, and a support enforcement agency in a proceeding under the
UUPA. See id. § 78B-15-607(1).
    ¶46 And the other three subsections of section 607 establish
guidelines generally applicable to proceedings under the UUPA. See
id. § 78B-15-607(2)–(4). They are written in the passive voice, so they
seemingly apply to all potential petitioners rather than a subset of
them.
_____________________________________________________________
   12As Mother points out, this provision is also found in Utah Code
subsection 30-1-17.2(4).


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                          Opinion of the Court

    ¶47 Subsection 607(2) states that when the child has a presumed
father as described in subsection 204(1)(d), 13 “the presumption may
be rebutted at any time if the tribunal determines that the presumed
father and the mother . . . neither cohabited nor engaged in sexual
intercourse with each other during the probable time of conception.”
   ¶48 Subsection 607(3) outlines how the presumption of
paternity may be rebutted: either by (a) “genetic test results that
exclude the presumed father”; (b) “genetic test results that rebuttably
identify another man as the father . . .”; (c) “evidence that the
presumed father and the mother of the child neither cohabited nor
engaged in sexual intercourse with each other during the probable
time of conception”; or (d) “an adjudication under this part.”
   ¶49 And finally subsection 607(4) states that “[t]here is no
presumption to rebut if the presumed father was properly served
and there has been a final adjudication of the issue.”
    ¶50 Contrary to Mother’s argument that section 607 governs
standing under the UUPA when a child has a presumed father, these
provisions do not relate to standing. They instruct potential
petitioners on how and when they may rebut the presumption of
paternity. For example, Castro states that he seeks to rebut
Husband’s paternity under subsection 607(3)(c) by showing that
Husband and Mother did not cohabitate or engage in sexual
intercourse during the probable time of conception. Accordingly, he
seeks to rebut Husband’s paternity in accordance with section 607, as
_____________________________________________________________
   13 Under subsection 204(1)(d), a man is presumed to be the child’s
father if
        (d) after the birth of the child, he and the mother of the
        child married each other in apparent compliance with
        law, whether or not the marriage is, or could be
        declared, invalid, he voluntarily asserted his paternity
        of the child, and there is no other presumptive father of
        the child, and:
           (i) the assertion is in a record filed with the Office of
           Vital Records;
           (ii) he agreed to be and is named as the child’s
           father on the child’s birth certificate; or
           (iii) he promised in a record to support the child as
           his own.


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                         Opinion of the Court

required by subsection 204(2). This is irrelevant to whether he has
standing.
   ¶51 Ultimately, the specific standing provision of the UUPA
grants standing to “a man whose paternity of the child is to be
adjudicated.” Id. § 78B-15-602(3). This seemingly includes Castro. We
conclude that subsection 607(1) does nothing to alter section 602. It
creates deadlines for the mother, presumed father, and support
enforcement agencies in a divorce proceeding, but it is silent as to
the others listed in section 602. And we do not interpret this silence
to revoke the standing of any of the persons or entities listed in
section 602. 14
    ¶52 We conclude this is the better reading of the statute. But we
need not go further to decide whether this is the plain and
unambiguous meaning of the relevant provisions because, even
assuming ambiguity existed, we would nevertheless adopt Castro’s
interpretation due to the serious constitutional issues raised by
Mother’s reading of the UUPA. See infra ¶¶ 53–60.
                II. CONSTITUTIONAL AVOIDANCE
   ¶53 In this and the companion cases in which we also issue
opinions today, alleged fathers have argued that if the UUPA denies
_____________________________________________________________
   14 We acknowledge the court of appeals’ concern that permitting
alleged fathers to challenge paternity could “discourag[e] the
presumed father from staying married to the mother and assuming
parental responsibilities for the child.” R.P., 2014 UT App 38, ¶ 24.
However, we note that any limitation that subsection 607(1) imposes
also applies in cases where there is no longer a marriage to protect.
Subsection 607(1) applies when a presumption of paternity arises
under subsections 204(1)(a), (b), or (c). Significantly, only
subsection 204(1)(a) is limited to a situation where the child is born
into an intact marriage. Under subsection 204(1)(b), the marriage was
terminated before the child was born. UTAH CODE § 78B-15-204(1)(b)
(“[The presumed father] and the mother of the child were married to
each other and the child is born within 300 days after the marriage is
terminated . . . .”). And subsection 204(1)(c) also includes marriages
that have ended. Id. § 78B-15-204(1)(c) (“[B]efore the birth of the
child, [the presumed father] and the mother of the child married
each other in apparent compliance with law, even if the attempted
marriage is or could be declared invalid, and the child is born during
the invalid marriage or within 300 days after its termination . . . .”).


                                  15
                          CASTRO v. LEMUS
                        Opinion of the Court

them standing, it is a violation of their procedural and substantive
due process rights and their right to equal protection under the state
and federal constitutions. See Hinkle v. Jacobsen, 2019 UT 72,
¶ 19, --- P.3d --- (arguing that the UUPA violates the due process and
equal protection clauses of the federal constitution); Olguin v.
Anderton, 2019 UT 73, ¶ 18, --- P.3d --- (arguing that the UUPA
violates alleged fathers’ procedural and substantive due process
rights under the state and federal constitutions); Mackley v.
Openshaw, 2019 UT 74, ¶ 2 n.2, --- P.3d --- (arguing that the UUPA
violates alleged fathers’ state and federal procedural and substantive
due process rights as well as principles of equal protection). In one
companion case, the district court ruled that the UUPA violated the
alleged father’s right to procedural due process. See Olguin, 2019 UT
73, ¶¶ 1, 9, 12.
    ¶54 We note that in R.P. v. K.S.W., the appellant did not raise
any constitutional challenges to the UUPA. See 2014 UT App 38,
¶¶ 7, 44, 320 P.3d 1084. Accordingly, the court of appeals left “for
another day the issue of the constitutional implications of the
UUPA’s standing limitations where the alleged father has an
established relationship with the child.” Id. ¶ 7.
    ¶55 However, parties are not required to invoke the canon of
constitutional avoidance before we may consider it when
interpreting a statute. State v. Garcia, 2017 UT 53, ¶ 52, 424 P.3d 171
(“[F]ailure to invoke the constitutional avoidance canon does not
deprive us of the ability to employ that canon to interpret the
statute.”). Indeed, “when statutory language is ambiguous—in that
its terms remain susceptible to two or more reasonable
interpretations after we have conducted a plain language analysis—
we generally resort to other modes of statutory construction and
seek guidance from legislative history and other accepted sources.”
Marion Energy, Inc. v. KFJ Ranch P’ship, 2011 UT 50, ¶ 15, 267 P.3d 863
(citation omitted) (internal quotation marks omitted). “The canon of
constitutional avoidance is an important tool for identifying and
implementing legislative intent.” Utah Dep’t of Transp. v. Carlson,
2014 UT 24, ¶ 23, 332 P.3d 900.
    ¶56 Under the canon of constitutional avoidance, courts may
“reject[] one of two plausible constructions of a statute on the
ground that it would raise grave doubts as to [the statute’s]
constitutionality.” Id. This practice “reflects the prudential concern
that constitutional issues not be needlessly confronted, but also
recognizes that [the legislature], like this [c]ourt, is bound by and
swears an oath to uphold the Constitution.” Edward J. DeBartolo Corp.

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                          Cite as: 2019 UT 71
                         Opinion of the Court

v. Fla. Gulf Coast Bldg. & Constr. Trades Council, 485 U.S. 568, 575
(1988). Thus, in applying the canon of constitutional avoidance, we
presume that “the legislature ‘either prefers not to press the limits of
the Constitution in its statutes, or it prefers a narrowed (and
constitutional) version of its statutes to a statute completely stricken’
by the courts.” Carlson, 2014 UT 24, ¶ 23 (quoting Richard L. Hansen,
Constitutional Avoidance and Anti-Avoidance by the Roberts Court, 2009
SUP. CT. REV. 181, 186).
    ¶57 Castro argues that if subsection 607(1) denies standing to
alleged fathers, it violates his state and federal constitutional rights
to procedural due process, substantive due process, and equal
protection. 15 The United States Supreme Court has recognized that
the Fourteenth Amendment protects parents’ liberty interest “in the
care, custody, and control of their children.” Troxel v. Granville, 530
U.S. 57, 65 (2000). But the Supreme Court has stated that “the mere
existence of a biological link” does not, in and of itself, merit
substantial protection under the Due Process Clause. Lehr v.
Robertson, 463 U.S. 248, 261 (1983). Instead, a biological link offers
biological fathers “an opportunity . . . to develop a relationship with
his offspring.” Id. at 262. If a biological father “com[es] forward to
participate in the rearing of his child” and “accepts some measure of
responsibility for the child’s future, he may enjoy the blessings of the
parent-child relationship.” Id. at 261–62 (citation omitted). If he fails
to do so, however, his interest in establishing such a relationship is
not afforded the same constitutional protections. See id. at 262.
    ¶58 In the adoption context, we have affirmed that due process
is satisfied if the Utah Code provides an unwed biological father
with “a meaningful chance to preserve his opportunity to develop a
relationship with his child.” In re Adoption of T.B., 2010 UT 42, ¶ 31,
232 P.3d 1026. The adoption code does this by providing that “an
unwed natural father may acquire the right to consent to an

_____________________________________________________________
   15 The Due Process Clause provides that “[n]o person shall be . . .
deprived of life, liberty, or property, without due process of law.”
U.S. CONST. amend. V. This guarantee was extended to the states
through the Fourteenth Amendment. Id. amend. XIV, § 1 (“No state
shall . . . deprive any person of life, liberty, or property, without due
process of law.”). The Equal Protection Clause states that “[n]o state
shall . . . deny to any person within its jurisdiction the equal
protection of the laws.” Id.


                                   17
                          CASTRO v. LEMUS
                        Opinion of the Court

adoption by satisfying certain statutory requirements,” including
initiating a paternity proceeding. Id. ¶ 26.
    ¶59 But a construction of subsection 607(1) that denies standing
to all alleged fathers 16 means that they have no opportunity to
initiate a paternity proceeding or preserve their opportunity to
develop a relationship with their children in any other manner. This
interpretation of subsection 607(1) raises questions as to the UUPA’s
constitutionality. The court of appeals recognized this in R.P. when it
stated that “constitutional considerations might require further
analysis in cases such as this—where the alleged father has an
established relationship with the child.” 2014 UT App 38, ¶ 7.
    ¶60 Because of the serious constitutional questions raised by an
interpretation of the UUPA that denies standing to all alleged fathers
when a presumed father exists, we would be compelled to adopt
Castro’s interpretation of the statute even if the relevant language
were ambiguous.
                           CONCLUSION
    ¶61 We conclude that section 78B-15-602 of the UUPA grants
standing to alleged fathers seeking to adjudicate their paternity, and
nothing in subsection 607(1) revokes that standing. We overrule R.P.
v. K.S.W., 2014 UT App 38, 320 P.3d 1084. And we reverse the district
court’s dismissal of Castro’s paternity petition and remand to the
district court for further proceedings.




_____________________________________________________________
   16The UUPA appears to address the viability of a claim by an
unwed biological father not through its standing provision, but
through subsection 104(3), which states that a “court shall, without
adjudicating paternity, dismiss a petition that is filed under this
chapter by an unmarried biological father if he is not entitled to
consent to the adoption of the child under [s]ections 78B-6-121 and
78B-6-122.”


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