concurring.
In 2005, mother stipulated that child should be in the custody of child’s paternal grandmother. The stipulation was incorporated into a dissolution judgment1 and, as such, was subject to the statutory and case law requirements for modification of such judgments, including the requirements that the modification is justified by a substantial change in circumstances and that the modification is in the best interests of the child. ORS 107.135; Travis and Potter, 236 Or App 563, 666, 237 P3d 868 (2010), rev den, 349 Or 603 (2011) (identifying requirements). In 2008, mother moved to modify the judgment; she sought custody of child, among other alternatives. The trial court denied mother’s motion, concluding (1) that mother had failed to show a substantial change in circumstances justifying modification of the custody judgment, and (2) that modifying the custody judgment was not in child’s best interests. Mother appeals.
*488The appeal requires us to determine, at least in part, the requirements that a parent must satisfy in order to have a court modify a stipulated custody judgment that awarded custody to a nonparent. Relying on Troxel v. Granville, 530 US 57, 120 S Ct 2054, 147 L Ed 2d 49 (2000), mother contends that she has a fundamental right to make custody decisions regarding her child and that, as a result, (1) she was not required to show a substantial change in circumstances in order to have the stipulated custody judgment modified, and (2) she was entitled to a presumption that her custody choice was in the best interests of child. Therefore, mother concludes, the trial court was required to award her custody of child, regardless of whether she established a substantial change in circumstances, unless there was sufficient evidence to overcome the presumption that her custody choice was in the best interests of child.
The lead opinion rejects both of mother’s contentions, whereas the dissent accepts both of them. I write separately because I would reject mother’s first contention and not reach her second one. That is, I would hold that (1) mother was required to establish a substantial change in circumstances in order to have the custody judgment modified, (2) the trial court did not err in concluding that mother had failed to establish such a change, and (3) because mother had failed to establish the requirement for the modification that she requested, we need not decide whether the trial court was required to presume that mother’s requested modification was in child’s best interests.
Both of mother’s contentions are based on Troxel, which involved the constitutionality of a Washington State statute that authorized a court to award a person the right to visitation with a child, if the court concluded that the visitation was in the child’s best interests, regardless of whether the parent objected to the visitation. In Troxel, the dispute over visitation was between a mother and the paternal grandparents of the mother’s two daughters. The mother, who had full custody of the daughters, objected to the amount of visitation that the grandparents sought. The Washington Superior Court awarded the grandparents visitation in an amount greater than the amount to which *489the mother had agreed. The mother appealed, and the case eventually reached the United States Supreme Court.
A plurality of the Supreme Court concluded that “the Due Process Clause of the Fourteenth Amendment [to the United States Constitution] protects the fundamental right of parents to make decisions concerning the care, custody, and control of their children.” Troxel, 530 US at 66. Addressing the specific issue before it, the Court held that the challenged state statute was unconstitutional as applied because it did not afford any special weight to the mother’s determination regarding the amount of visitation that was in the best interest of her daughters. The Court explained, “[T]here is a presumption that fit parents act in the best interests of their children.” Id. at 68. “Accordingly, so long as a parent adequately cares for his or her children (i.e., is fit), there will normally be no reason for the State to inject itself into the private realm of the family to further question the ability of that parent to make the best decisions concerning the rearing of that parent’s children.” Id. at 68-69. The Court further explained, “The problem here is not that the Washington Superior Court intervened, but that when it did so, it gave no special weight at all to [the mother’s] determination of her daughters’ best interests [,]” id. at 69; instead, it appeared to presume that the amount of visitation awarded by the court was in the children’s best interests. As a result,
“[t]he decisional framework employed by the Superior Court directly contravened the traditional presumption that a fit parent will act in the best interest of his or her child. * * * In that respect, the court’s presumption failed to provide any protection for [the mother’s] fundamental constitutional right to make decisions concerning the rearing of her own daughters.”
Id. at 69-70. Accordingly, the Supreme Court concluded that the challenged state statute was unconstitutional as applied.
In Troxel, the Supreme Court went on to note that it was not defining “the precise scope of the parental due process right in the visitation context,” id. at 73, and that “the constitutionality of any standard for awarding visitation turns on the specific manner in which that standard is *490applied and that the constitutional protections in this area are best ‘elaborated with care[,]’” id. (quoting id. at 100) (Kennedy, J., dissenting). Thus, as the Oregon Supreme Court has stated, the Troxel court did not clearly “identify the scope of the parental rights protected by the Due Process Clause * * *.” O’Donnell-Lamont and Lamont, 337 Or 86, 100, 91 P3d 721 (2004), cert den, 543 US 1050 (2005).
The facts of Troxel differ in two significant respects from the facts of this case. First, in this case, the proceedings before the trial court were modification proceedings; mother had already stipulated to a judgment awarding grandmother custody of child. Thus, the state had already “inject [ed] itself into the private realm of the family.” Troxel, 530 US at 68. Second, and as a result of the stipulated custody judgment, mother did not have custody over child at the time of the proceedings, raising the question of whether the Troxel presumption applies.
Mother’s first contention is that she is not required to establish a substantial change in circumstances in order to have the stipulated custody judgment modified. Essentially, mother’s position is that she has a fundamental right to make custody decisions and that that right is not limited in any way by the fact that she already has stipulated to a judgment awarding grandmother custody. Because Troxel did not involve a modification proceeding, it provides limited guidance. Troxel can be fairly read as establishing that fit parents have a fundamental right to make custody decisions for their children and that, to give effect to that right, fit parents are entitled to a presumption that they act in the best interests of their children, at least during an initial custody determination. Troxel, 530 US at 66-68. But those principles do not resolve the issue in this case, which does not involve an initial custody determination.
Obviously, there are competing interests at stake when a parent seeks to modify a stipulated judgment awarding custody to a nonparent. On the one hand is the parent’s interest in deciding the custody of the child, and on the other hand is the interest in the durability of the judgment and the related security that the judgment provides to the *491child and the custodian. See State ex rel Johnson v. Bail, 325 Or 392, 398, 938 P2d 209 (1997) (“The rationale for the change-in-circumstances rule is that, unless the parent who seeks a change in custody establishes that the facts that formed the basis for the prior custody determination have changed materially by the time of the modification hearing, the prior adjudication is preclusive with respect to the issue of the best interests of the child under the extant facts [,]” and “[t]he purposes served by the change-in-circumstances rule are to avoid repeated litigation over custody and to provide a stable environment for children.” (Internal quotation marks and citations omitted.)). In my view, requiring a parent who has stipulated to a custody judgment to establish a substantial change in circumstances before the judgment may be modified does not unduly burden the parent’s due process rights. Invocation of the state’s authority, through the courts, to enter a custody judgment has consequences. Generally, when a parent knowingly and voluntarily stipulates to a custody judgment, the parent can be understood to have agreed to the legal requirements for modifying that judgment.2 The Due Process Clause does not, in my view, prohibit enforcement of those requirements. In other words, the Due Process Clause does not guarantee a parent the right to modify a stipulated custody judgment for any reason, or no reason, at all.
Here, the trial court concluded that mother had not proved a substantial change in circumstances. It appears that the trial court did not credit mother’s testimony that she no longer had any mental health or substance abuse problems. As the lead opinion explains, “the trial court was not required to find mother’s testimony to be credible * * * [and there is] no reason to disturb the trial court’s findings on appeal.” 258 Or App at 476.
Because mother did not satisfy the threshold requirement for modification of the stipulated judgment, there is no need to determine whether modification was in child’s best interests and, relatedly, whether mother was entitled to a presumption that it was. Therefore, I would not reach the merits of mother’s second contention.
*492For the foregoing reasons, I join in the portion of the lead opinion that holds that mother was required to establish a substantial change in circumstances in order to have the stipulated custody judgment modified, but I do not join in the portion of the lead opinion that holds that parents who have stipulated to a judgment awarding custody to a nonparent are not entitled to a presumption that they act in the best interests of their children.
Ortega, J., joins in this concurrence.
As the lead opinion recounts, mother and father executed a marital settlement agreement stating that they “desire[d] that [grandmother], be awarded sole legal and physical custody of [child], subject to the joint right of both Husband and Wife to equally share the parenting time ***.” The agreement also stated that grandmother had “exclusive discretion in day-to-day parenting, routine medical and dental matters, [and] interaction with school authorities,” and “full emergency authority to seek aid for the child under whatever circumstances [grandmother] deemled] appropriate.” The settlement agreement was incorporated into the stipulated dissolution judgment, which itself stated that “[grandmother] * * * is awarded sole legal and physical custody of [child], subject to the joint right of both Husband and Wife to parenting time * *
Of course, parties can agree to reduce the requirements for modification.