Justice Stevens
delivered the opinion of the Court.
The question presented is whether New York has sufficiently protected an unmarried father’s inchoate relationship with a child whom he has never supported and rarely seen in the two years since her birth. The appellant, Jonathan Lehr, claims that the Due Process and Equal Protection Clauses of the Fourteenth Amendment, as interpreted in Stanley v. Illinois, 405 U. S. 645 (1972), and Caban v. Mohammed, 441 U. S. 380 (1979), give him an absolute right to notice and an opportunity to be heard before the child may be adopted. We disagree.
Jessica M. was born out of wedlock on November 9, 1976. Her mother, Lorraine Robertson, married Richard Robertson eight months after Jessica’s birth. On December 21, 1978, when Jessica was over two years old, the Robertsons filed an adoption petition in the Family Court of Ulster County, New York. The court heard their testimony and received a favorable report from the Ulster County Department of Social Services. On March 7, 1979, the court entered an order of adoption. In this proceeding, appellant contends that the adoption order is invalid because he, Jessica’s putative father, was not given advance notice of the adoption proceeding.
The State of New York maintains a “putative father registry.” A man who files with that registry demonstrates his intent to claim paternity of a child born out of wedlock and is therefore entitled to receive notice of any proceeding to adopt that child. Before entering Jessica’s adoption order, the Ulster County Family Court had the putative father registry examined. Although appellant claims to be Jessica’s natural father, he had not entered his name in the registry.
In addition to the persons whose names are listed on the putative father registry, New York law requires that notice of an adoption proceeding be given to several other classes of possible fathers of children born out of wedlock — those who have been adjudicated to be the father, those who have been identified as the father on the child’s birth certificate, those who live openly with the child and the child’s mother and who hold themselves out to be the father, those who have been identified as the father by the mother in a sworn written statement, and those who were married to the child’s mother before the child was six months old. Appellant admittedly was not a member of any of those classes. He had lived with appellee prior to Jessica’s birth and visited her in the hospital when Jessica was born, but his name does not appear on Jessica’s birth certificate. He did not live with appellee or Jessica after Jessica’s birth, he has never provided them with any financial support, and he has never offered to marry appellee. Nevertheless, he contends that the following special circumstances gave him a constitutional right to notice and a hearing before Jessica was adopted.
On January 30, 1979, one month after the adoption proceeding was commenced in Ulster County, appellant filed a “visitation and paternity petition” in the Westchester County Family Court. In that petition, he asked for a determination of paternity, an order of support, and reasonable visitation privileges with Jessica. Notice of that proceeding was served on appellee on February 22, 1979. Four days later appellee’s attorney informed the Ulster County Court that appellant had commenced a paternity proceeding in West-chester County; the Ulster County judge then entered an order staying appellant’s paternity proceeding until he could rule on a motion to change the venue of that proceeding to Ulster County. On March 3, 1979, appellant received notice of the change of venue motion and, for the first time, learned that an adoption proceeding was pending in Ulster County.
On March 7, 1979, appellant’s attorney telephoned the Ulster County judge to inform him that he planned to seek a stay of the adoption proceeding pending the determination of the paternity petition. In that telephone conversation, the judge advised the lawyer that he had already signed the adoption order earlier that day. According to appellant’s attorney, the judge stated that he was aware of the pending paternity petition but did not believe he was required to give notice to appellant prior to the entry of the order of adoption.
Thereafter, the Family Court in Westchester County granted appellee’s motion to dismiss the paternity petition, holding that the putative father’s right to seek paternity “must be deemed severed so long as an order of adoption exists.” App. 228. Appellant did not appeal from that dismissal. On June 22,1979, appellant filed a petition to vacate the order of adoption on the ground that it was obtained by fraud and in violation of his constitutional rights. The Ulster County Family Court received written and oral argument on the question whether it had “dropped the ball” by approving the adoption without giving appellant advance notice. Tr. 53. After deliberating for several months, it denied the petition, explaining its decision in a thorough written opinion. In re Adoption of Martz, 102 Misc. 2d 102, 423 N. Y. S. 2d 378 (1979).
The Appellate Division of the Supreme Court affirmed. In re Adoption of Jessica “XX,” 77 App. Div. 2d 381, 434 N. Y. S. 2d 772 (1980). The majority held that appellant’s commencement of a paternity action did not give him any right to receive notice of the adoption proceeding, that the notice provisions of the statute were constitutional, and that Caban v. Mohammed, 441 U. S. 380 (1979), was not retroactive. Parenthetically, the majority observed that appellant “could have insured his right to notice by signing the putative father registry.” 77 App. Div. 2d, at 383, 434 N. Y. S. 2d, at 774. One justice dissented on the ground that the filing of the paternity proceeding should have been viewed as the statutory equivalent of filing a notice of intent to claim paternity with the putative father registry.
The New York Court of Appeals also affirmed by a divided vote. In re Adoption of Jessica “XX,” 54 N. Y. 2d 417, 430 N. E. 2d 896 (1981). The majority first held that it did not need to consider whether our decision in Caban affected appellant’s claim that he had a right to notice, because Caban was not retroactive. It then rejected the argument that the mother had been guilty of a fraud upon the court. Finally, it addressed what it described as the only contention of substance advanced by appellant: that it was an abuse of discretion to enter the adoption order without requiring that notice be given to appellant. The court observed that the primary purpose of the notice provision of § 111-a was to enable the person served to provide the court with evidence concerning the best interest of the child, and that appellant had made no tender indicating any ability to provide any particular or special information relevant to Jessica’s best interest. Considering the record as a whole, and acknowledging that it might have been prudent to give notice, the court concluded that the Family Court had not abused its discretion either when it entered the order without notice or when it denied appellant’s petition to reopen the proceedings. The dissenting judges concluded that the Family Court had abused its discretion, both when it entered the order without notice and when it refused to reopen the proceedings.
Appellant has now invoked our appellate jurisdiction. He offers two alternative grounds for holding the New York statutory scheme unconstitutional. First, he contends that a putative father’s actual or potential relationship with a child born out of wedlock is an interest in liberty which may not be destroyed without due process of law; he argues therefore that he had a constitutional right to prior notice and an opportunity to be heard before he was deprived of that interest. Second, he contends that the gender-based classification in the statute, which both denied him the right to consent to Jessica’s adoption and accorded him fewer procedural rights than her mother, violated the Equal Protection Clause.
The Due Process Claim.
The Fourteenth Amendment provides that no State shall deprive any person of life, liberty, or property without due process of law. When that Clause is invoked in a novel context, it is our practice to begin the inquiry with a determination of the precise nature of the private interest that is threatened by the State. See, e. g., Cafeteria Workers v. McElroy, 367 U. S. 886, 895-896 (1961). Only after that interest has been identified, can we properly evaluate the adequacy of the State’s process. See Morrissey v. Brewer, 408 U. S. 471, 482-483 (1972). We therefore first consider the nature of the interest in liberty for which appellant claims constitutional protection and then turn to a discussion of the adequacy of the procedure that New York has provided for its protection.
I
The intangible fibers that connect parent and child have infinite variety. They are woven throughout the fabric of our society, providing it with strength, beauty, and flexibility. It is self-evident that they are sufficiently vital to merit constitutional protection in appropriate cases. In deciding whether this is such a case, however, we must consider the broad framework that has traditionally been used to resolve the legal problems arising from the parent-child relationship.
In the vast majority of cases, state law determines the final outcome. Cf. United States v. Yazell, 382 U. S. 341, 351— 353 (1966). Rules governing the inheritance of property, adoption, and child custody are generally specified in statutory enactments that vary from State to State. Moreover, equally varied state laws governing marriage and divorce affect a multitude of parent-child relationships. The institution of marriage has played a critical role both in defining the legal entitlements of family members and in developing the decentralized structure of our democratic society. In recognition of that role, and as part of their general overarching concern for serving the best interests of children, state laws almost universally express an appropriate preference for the formal family.
In some cases, however, this Court has held that the Federal Constitution supersedes state law and provides even greater protection for certain formal family relationships. In those cases, as in the state cases, the Court has emphasized the paramount interest in the welfare of children and has noted that the rights of the parents are a counterpart of the responsibilities they have assumed. Thus, the “liberty” of parents to control the education of their children that was vindicated in Meyer v. Nebraska, 262 U. S. 390 (1923), and Pierce v. Society of Sisters, 268 U. S. 510 (1925), was described as a “right, coupled with the high duty, to recognize and prepare [the child] for additional obligations.” Id., at 535. The linkage between parental duty and parental right was stressed again in Prince v. Massachusetts, 321 U. S. 158, 166 (1944), when the Court declared it a cardinal principle “that the custody, care and nurture of the child reside first in the parents, whose primary function and freedom include preparation for obligations the state can neither supply nor hinder.” Ibid. In these cases the Court has found that the relationship of love and duty in a recognized family unit is an interest in liberty entitled to constitutional protection. See also Moore v. City of East Cleveland, 431 U. S. 494 (1977) (plurality opinion). “[S]tate intervention to terminate [such a] relationship . . . must be accomplished by procedures meeting the requisites of the Due Process Clause.” Santosky v. Kramer, 455 U. S. 745, 753 (1982).
There are also a few cases in which this Court has considered the extent to which the Constitution affords protection to the relationship between natural parents and children born out of wedlock. In some we have been concerned with the rights of the children, see, e. g., Trimble v. Gordon, 430 U. S. 762 (1977); Jimenez v. Weinberger, 417 U. S. 628 (1974); Weber v. Aetna Casualty & Surety Co., 406 U. S. 164 (1972). In this case, however, it is a parent who claims that the State has improperly deprived him of a protected interest in liberty. This Court has examined the extent to which a natural father’s biological relationship with his child receives protection under the Due Process Clause in precisely three cases: Stanley v. Illinois, 405 U. S. 645 (1972), Quilloin v. Walcott, 434 U. S. 246 (1978), and Caban v. Mohammed, 441 U. S. 380 (1979).
Stanley involved the constitutionality of an Illinois statute that conclusively presumed every father of a child born out of wedlock to be an unfit person to have custody of his children. The father in that case had lived with his children all their lives and had lived with their mother for 18 years. There was nothing in the record to indicate that Stanley had been a neglectful father who had not cared for his children. 405 U. S., at 655. Under the statute, however, the nature of the actual relationship between parent and child was completely irrelevant. Once the mother died, the children were automatically made wards of the State. Relying in part on a Michigan case recognizing that the preservation of “a subsisting relationship with the child’s father” may better serve the child’s best interest than “uprooting him from the family which he knew from birth,” id., at 654-655, n. 7, the Court held that the Due Process Clause was violated by the automatic destruction of the custodial relationship without giving the father any opportunity to present evidence regarding his fitness as a parent.
Quilloin involved the constitutionality of a Georgia statute that authorized the adoption, over the objection of the natural father, of a child born out of wedlock. The father in that case had never legitimated the child. It was only after the mother had remarried and her new husband had filed an adoption petition that the natural father sought visitation rights and filed a petition for legitimation. The trial court found adoption by the new husband to be in the child’s best interests, and we unanimously held that action to be consistent with the Due Process Clause.
Caban involved the conflicting claims of two natural parents who had maintained joint custody of their children from the time of their birth until they were respectively two and four years old. The father challenged the validity of an order authorizing the mother’s new husband to adopt the children; he relied on both the Equal Protection Clause and the Due Process Clause. Because this Court upheld his equal protection claim, the majority did not address his due process challenge. The comments on the latter claim by the four dissenting Justices are nevertheless instructive, because they identify the clear distinction between a mere biological relationship and an actual relationship of parental responsibility.
Justice Stewart correctly observed:
“Even if it be assumed that each married parent after divorce has some substantive due process right to maintain his or her parental relationship, cf. Smith v. Organization of Foster Families, 431 U. S. 816, 862-863 (opinion concurring in judgment), it by no means follows that each unwed parent has any such right. Parental rights do not spring full-blown from the biological connection between parent and child. They require relationships more enduring.” 441 U. S., at 397 (emphasis added).
In a similar vein, the other three dissenters in Caban were prepared to “assume that, if and when one develops, the relationship between a father and his natural child is entitled to protection against arbitrary state action as a matter of due process.” Caban v. Mohammed, supra, at 414 (emphasis added).
The difference between the developed parent-child relationship that was implicated in Stanley and Caban, and the potential relationship involved in Quilloin and this case, is both clear and significant. When an unwed father demonstrates a full commitment to the responsibilities of parenthood by “com[ing] forward to participate in the rearing of his child,” Caban, 441 U. S., at 392, his interest in personal contact with his child acquires substantial protection under the Due Process Clause. At that point it may be said that he “act[s] as a father toward his children.” Id., at 389, n. 7. But the mere existence of a biological link does not merit equivalent constitutional protection. The actions of judges neither create nor sever genetic bonds. “[T]he importance of the familial relationship, to the individuals involved and to the society, stems from the emotional attachments that derive from the intimacy of daily association, and from the role it plays in ‘promoting] a way of life’ through the instruction of children ... as well as from the fact of blood relationship.” Smith v. Organization of Foster Families for Equality and Reform, 431 U. S. 816, 844 (1977) (quoting Wisconsin v. Yoder, 406 U. S. 205, 231-233 (1972)).
The significance of the biological connection is that it offers the natural father an opportunity that no other male possesses to develop a relationship with his offspring. If he grasps that opportunity and accepts some measure of responsibility for the child’s future, he may enjoy the blessings of the parent-child relationship and make uniquely valuable contributions to the child’s development. If he fails to do so, the Federal Constitution will not automatically compel a State to listen to his opinion of where the child’s best interests lie.
In this case, we are not assessing the constitutional adequacy of New York’s procedures for terminating a developed relationship. Appellant has never had any significant custodial, personal, or financial relationship with Jessica, and he did not seek to establish a legal tie until after she was two years old. We are concerned only with whether New York has adequately protected his opportunity to form such a relationship.
II
The most effective protection of the putative father’s opportunity to develop a relationship with his child is provided by the laws that authorize formal marriage and govern its consequences. But the availability of that protection is, of course, dependent on the will of both parents of the child. Thus, New York has adopted a special statutory scheme to protect the unmarried father’s interest in assuming a responsible role in the future of his child.
After this Court’s decision in Stanley, the New York Legislature appointed a special commission to recommend legislation that would accommodate both the interests of biological fathers in their children and the children’s interest in prompt and certain adoption procedures. The commission recommended, and the legislature enacted, a statutory adoption scheme that automatically provides notice to seven categories of putative fathers who are likely to have assumed some responsibility for the care of their natural children. If this scheme were likely to omit many responsible fathers, and if qualification for notice were beyond the control of an interested putative father, it might be thought procedurally inadequate. Yet, as all of the New York courts that reviewed this matter observed, the right to receive notice was completely within appellant’s control. By mailing a postcard to the putative father registry, he could have guaranteed that he would receive notice of any proceedings to adopt Jessica. The possibility that he may have .failed to do so because of his ignorance of the law cannot be a sufficient reason for criticizing the law itself. The New York Legislature concluded that a more open-ended notice requirement would merely complicate the adoption process, threaten the privacy interests of unwed mothers, create the risk of unnecessary controversy, and impair the desired finality of adoption decrees. Regardless of whether we would have done likewise if we were legislators instead of judges, we surely cannot characterize the State’s conclusion as arbitrary.
Appellant argues, however, that even if the putative father’s opportunity to establish a relationship with an illegitimate child is adequately protected by the New York statutory scheme in the normal case, he was nevertheless entitled to special notice because the court and the mother knew that he had filed an affiliation proceeding in another court. This argument amounts to nothing more than an indirect attack on the notice provisions of the New York statute. The legitimate state interests in facilitating the adoption of young children and having the adoption proceeding completed expeditiously that underlie the entire statutory scheme also justify a trial judge’s determination to require all interested parties to adhere precisely to the procedural requirements of the statute. The Constitution does not require either a trial judge or a litigant to give special notice to nonparties who are presumptively capable of asserting and protecting their own rights. Since the New York statutes adequately protected appellant’s inchoate interest in establishing a relationship with Jessica, we find no merit in the claim that his constitutional rights were offended because the Family Court strictly complied with the notice provisions of the statute.
The Equal Protection Claim.
The concept of equal justice under law requires the State to govern impartially. New York City Transit Authority v. Beazer, 440 U. S. 568, 587 (1979). The sovereign may not draw distinctions between individuals based solely on differences that are irrelevant to a legitimate governmental objective. Reed v. Reed, 404 U. S. 71, 76 (1971). Specifically, it may not subject men and women to disparate treatment when there is no substantial relation between the disparity and an important state purpose. Ibid.; Craig v. Boren, 429 U. S. 190, 197-199 (1976).
The legislation at issue in this case, N. Y. Dom. Rel. Law §§ 111 and 111-a (McKinney 1977 and Supp. 1982-1983), is intended to establish procedures for adoptions. Those procedures are designed to promote the best interests of the child, to protect the rights of interested third parties, and to ensure promptness and finality. To serve those ends, the legislation guarantees to certain people the right to veto an adoption and the right to prior notice of any adoption proceeding. The mother of an illegitimate child is always within that favored class, but only certain putative fathers are included. Appellant contends that the gender-based distinction is invidious.
As we have already explained, the existence or nonexistence of a substantial relationship between parent and child is a relevant criterion in evaluating both the rights of the parent and the best interests of the child. In Quilloin v. Walcott, we noted that the putative father, like appellant, “ha[d] never shouldered any significant responsibility with respect to the daily supervision, education, protection, or care of the child. Appellant does not complain of his exemption from these responsibilities . . . .” 434 U. S., at 256. We therefore found that a Georgia statute that always required a mother’s consent to the adoption of a child born out of wedlock, but required the father’s consent only if he had legitimated the child, did not violate the Equal Protection Clause. Because appellant, like the father in Quilloin, has never established a substantial relationship with his daughter, see supra, at 262, the New York statutes at issue in this case did not operate to deny appellant equal protection.
We have held that these statutes may not constitutionally be applied in that class of cases where the mother and father are in fact similarly situated with regard to their relationship with the child. In Caban v. Mohammed, 441 U. S. 380 (1979), the Court held that it violated the Equal Protection Clause to grant the mother a veto over the adoption of a 4-year-old girl and a 6-year-old boy, but not to grant a veto to their father, who had admitted paternity and had participated in the rearing of the children. The Court made it clear, however, that if the father had not “come forward to participate in the rearing of his child, nothing in the Equal Protection Clause [would] preclud[e] the State from withholding from him the privilege of vetoing the adoption of that child.” Id., at 392.
Jessica’s parents are not like the parents involved in Caban. Whereas appellee had a continuous custodial responsibility for Jessica, appellant never established any custodial, personal, or financial relationship with her. If one parent has an established custodial relationship with the child and the other parent has either abandoned or never estab-fished a relationship, the Equal Protection Clause does not prevent a State from according the two parents different legal rights.
The judgment of the New York Court of Appeals is
Affirmed.
Although both Lorraine and Richard Robertson are appellees in this proceeding, for ease of discussion the term “appellee” will hereafter be used to identify Lorraine Robertson.
The order provided for the adoption of appellee’s older daughter, Renee, as well as Jessica. Appellant does not challenge the adoption of Renee.
Appellee has never conceded that appellant is Jessica’s biological father, but for purposes of analysis in this opinion it will be assumed that he is.
At the time Jessica’s adoption order was entered, N. Y. Soc. Serv. Law § 372-c (McKinney Supp. 1982-1983) provided:
“1. The department shall establish a putative father registry which shall record the names and addresses of. . . any person who has filed with the registry before or after the birth of a child out-of-wedlock, a notice of intent to claim paternity of the child ....
“2. A person filing a notice of intent to claim paternity of a child ... shall include therein his current address and shall notify the registry of any change of address pursuant to procedures prescribed by regulations of the department.
“3. A person who has filed a notice of intent to claim paternity may at any time revoke a notice of intent to claim paternity previously filed therewith and, upon receipt of such notification by the registry, the revoked notice of intent to claim paternity shall be deemed a nullity nunc pro tunc.
“4. An unrevoked notice of intent to claim paternity of a child may be introduced in evidence by any party, other than the person who filed such notice, in any proceeding in which such fact may be relevant.
“5. The department shall, upon request, provide the names and addresses of persons listed with the registry to any court or authorized agency, and such information shall not be divulged to any other person, except upon order of a court for good cause shown.”
At the time Jessica’s adoption order was entered, N. Y. Dom. Rel. Law §§ 111-a (2) and (3) (McKinney 1977 and Supp. 1982-1983) provided:
“2. Persons entitled to notice, pursuant to subdivision one of this section, shall include:
“(a) any person adjudicated by a court in this state to be the father of the child;
“(b) any person adjudicated by a court of another state or territory of the United States to be the father of the child, when a certified copy of the court order has been filed with the putative father registry, pursuant to section three hundred seventy-two-c of the social services law;
“(e) any person who has timely filed an unrevoked notice of intent to claim paternity of the child, pursuant to section three hundred seventy-two of the social services law;
“(d) any person who is recorded on the child’s birth certificate as the child’s father;
“(e) any person who is openly living with the child and the child’s mother at the time the proceeding is initiated and who is holding himself out to be the child’s father;
“(f) any person who has been identified as the child’s father by the mother in written, sworn statement; and
“(g) any person who was married to the child’s mother within six months subsequent to the birth of the child and prior to the execution of a surrender instrument or the initiation of a proceeding pursuant to section three hundred eighty-four-b of the social services law.
“3. The sole purpose of notice under this section shall be to enable the person served pursuant to subdivision two to present evidence to the court relevant to the best interests of the child.”
Without trying to intervene in the adoption proceeding, appellant had attempted to file an appeal from the adoption order. That appeal was dismissed.
Caban was decided on April 24, 1979, about two months after the entry of the order of adoption. In Caban, a father who had lived with his two illegitimate children and their mother for several years successfully challenged the constitutionality of the New York statute providing that children could be adopted without the father’s consent even though the mother’s consent was required.
Although the dissenters in Caban discussed the question of retroactivity, see 441 U. S., at 401, 415-416, that question was not addressed in the Court’s opinion.
We postponed consideration of our jurisdiction until after hearing argument on the merits. 456 U. S. 970 (1982). Our review of the record persuades us that appellant did in fact draw into question the validity of the New York statutory scheme on the ground of its being repugnant to the Federal Constitution, that the New York Court of Appeals upheld that scheme, and that we therefore have jurisdiction pursuant to 28 U. S. C. § 1257(2).
The question whether the Family Court abused its discretion in not requiring notice to appellant before the adoption order was entered and in not reopening the proceeding is, of course, not before us. That issue was presented to and decided by the New York courts purely as a matter of state law. Whether we might have given such notice had we been sitting as the trial court, or whether we might have considered the failure to give such notice an abuse of discretion had we been sitting as state appellate judges, are questions on which we are not authorized to express an opinion. The only question we have jurisdiction to decide is whether the New York statutes are unconstitutional because they inadequately protect the natural relationship between parent and child or because they draw an impermissible distinction between the rights of the mother and the rights of the father.
At present, state legislatures appear inclined to retain the unique attributes of their respective bodies of family law. For example, as of the end of 1982, only eight States had adopted the Uniform Parentage Act. 9A U. L. A. 171 (Supp. 1983).
See Hafen, Marriage, Kinship, and Sexual Privacy, 81 Mich. L. Rev. 463, 479-481 (1983).
See Trimble v. Gordon, 430 U. S. 762, 769 (1977) (“No one disputes the appropriateness of Illinois’ concern with the family unit, perhaps the most fundamental social institution of our society”). A plurality of the Court noted the societal value of family bonds in Moore v. City of East Cleveland, 431 U. S. 494, 505 (1977) (opinion of Powell, J.):
“Out of choice, necessity, or a sense of family responsibility, it has been common for close relatives to draw together and participate in the duties and the satisfactions of a common home. . . . Especially in times of adversity, such as the death of a spouse or economic need, the broader family has tended to come together for mutual sustenance and to maintain or rebuild a secure home life.”
In re Mark T., 8 Mich. App. 122, 154 N. W. 2d 27 (1967).
Having “concluded that all Illinois parents are constitutionally entitled to a hearing on their fitness before their children are removed from their custody,” the Court also held “that denying such a hearing to Stanley and those like him while granting it to other Illinois parents is inescapably contrary to the Equal Protection Clause.” 405 U. S., at 658.
In the balance of that paragraph Justice Stewart noted that the relation between a father and his natural child may acquire constitutional protection if the father enters into a traditional marriage with the mother or if “the actual relationship between father and child” is sufficient.
“The mother carries and bears the child, and in this sense her parental relationship is clear. The validity of the father’s parental claims must be gauged by other measures. By tradition, the primary measure has been the legitimate familial relationship he creates with the child by marriage with the mother. By definition, the question before us can arise only when no such marriage has taken place. In some circumstances the actual relationship between father and child may suffice to create in the unwed father parental interests comparable to those of the married father. Cf. Stanley v. Illinois, supra. But here we are concerned with the rights the unwed father may have when his wishes and those of the mother are in conflict, and the child’s best interests are served by a resolution in favor of the mother. It seems to me that the absence of a legal tie with the mother may in such circumstances appropriately place a limit on whatever substantive constitutional claims might otherwise exist by virtue of the father’s actual relationship with the children.” 441 U. S., at 397.
Commentators have emphasized the constitutional importance of the distinction between an inchoate and a fully developed relationship. See Comment, 46 Brooklyn L. Rev. 95, 115-116 (1979) (“the unwed father’s interest springs not from his biological tie with his illegitimate child, but rather, from the relationship he has established with and the responsibility he has shouldered for his child”); Note, 58 Neb. L. Rev. 610, 617 (1979) (“a putative father’s failure to show a substantial interest in his child’s welfare and to employ methods provided by state law for solidifying his parental rights . . . will remove from him the full constitutional protection afforded the parental rights of other classes of parents”); Note, 29 Emory L. J. 833, 854 (1980) (“an unwed father’s rights in his child do not spring solely from the biological fact of his parentage, but rather from his willingness to admit his paternity and express some tangible interest in the child”). See also Poulin, Illegitimacy and Family Privacy: A Note on Maternal Cooperation in Paternity Suits, 70 Nw. U. L. Rev. 910, 916-919 (1976) (hereinafter Poulin); Developments in the Law, 93 Harv. L. Rev. 1156, 1275-1277 (1980); Note, 18 Duquesne L. Rev. 375, 383-384, n. 73 (1980); Note, 19 J. Family L. 440, 460 (1980); Note, 57 Denver L. J. 671, 680-683 (1980); Note, 1979 Wash. U. L. Q. 1029,1035; Note, 12 U. C. D. L. Rev. 412, 450, n. 218 (1979).
Of course, we need not take sides in the ongoing debate among family psychologists over the relative weight to be accorded biological ties and psychological ties, in order to recognize that a natural father who has played a substantial role in rearing his child has a greater claim to constitutional protection than a mere biological parent. New York's statutory scheme reflects these differences, guaranteeing notice to any putative father who is living openly with the child, and providing putative fathers who have never developed a relationship with the child the opportunity to receive notice simply by mailing a postcard to the putative father registry.
This case happens to involve an adoption by the husband of the natural mother, but we do not believe the natural father has any greater right to object to such an adoption than to an adoption by two total strangers. If anything, the balance of equities tips the opposite way in a case such as this. In denying the putative father relief in Quilloin v. Walcott, 434 U. S. 246 (1978), we made an observation equally applicable here:
“Nor is this a case in which the proposed adoption would place the child with a new set of parents with whom the child had never before lived. Rather, the result of the adoption in this case is to give full recognition to a family unit already in existence, a result desired by all concerned, except appellant. Whatever might be required in other situations, we cannot say that the State was required in this situation to find anything more than that the adoption, and denial of legitimation, were in the ‘best interests of the child.’” Id,., at 255.
In a report explaining the purpose of the 1976 amendments to § 111-a of the New York Domestic Relations Law, the temporary state commission on child welfare that was responsible for drafting the legislation stated, in part:
“The measure will dispel uncertainties by providing clear constitutional statutory guidelines for notice to fathers of out-of-wedlock children. It will establish a desired finality in adoption proceedings and will provide an expeditious method for child placement agencies of identifying those fathers who are entitled to notice through the creation of a registry of such fathers within the State Department of Social Services. Conversely, the bill will afford to concerned fathers of out-of-wedlock children a simple means of expressing their interest and protecting their rights to be notified and have an opportunity to be heard. It will also obviate an existing disparity of Appellate Division decisions by permitting such fathers to be petitioners in paternity proceedings.
“The measure is intended to codify the minimum protections for the putative father which Stanley would require. In so doing it reflects policy decisions to (a) codify constitutional requirements; (b) clearly establish, as early as possible in a child’s life, the rights, interests and obligations of all parties; (c) facilitate prompt planning for the future of the child and permanence of his status; and (d) through the foregoing, promote the best interest of children.” App. to Brief for Appellant C-15.
Cf. Roe v. Norton, 422 U. S. 391 (1975), vacating and remanding 365 F. Supp. 65 (Conn. 1973). See Poulin 922-932; Barron, Notice to the Unwed Father and Termination of Parental Rights, 9 Family L. Q. 527, 542 (1975).
Nor can we deem unconstitutionally arbitrary the state courts’ conclusion that appellant’s absence did not distort their analysis of Jessica’s best interests. The adoption does not affect Jessica’s relationship with her mother. It gives legal permanence to her relationship with her adoptive father, a relationship they had maintained for 21 months at the time the adoption order was entered. Appellant did not proffer any evidence to suggest that legal confirmation of the established relationship would be unwise; he did not even know the adoptive father.
It is a generally accepted feature of our adversary system that a potential defendant who knows that the statute of limitations is about to run has no duty to give the plaintiff advice. There is no suggestion in the record that appellee engaged in fraudulent practices that led appellant not to protect his rights.
In Reed, the Court considered an Idaho statute providing that in designating administrators of the estates of intestate decedents, “[o]f several persons claiming and equally entitled to administer, males must be preferred to females.” See 404 U. S., at 73. The State had sought to justify the statute as a way to reduce the workload of probate courts by eliminating one class of contests. Writing for a unanimous Court, The Chief Justice observed that in using gender to promote that objective, the legislature had made “the very kind of arbitrary legislative choice forbidden by the Equal Protection Clause.” Id,., at 76. The State’s articulated goal could have been completely served by requiring a coin flip. The decision instead to choose a rule that systematically harmed women could be explained only as the product of habit, rather than analysis or reflection, cf. Califano v. Goldfarb, 430 U. S. 199, 222 (1977) (Stevens, J., concurring in judgment), or as the product of an invidious and indefensible stereotype, cf. id., at 218. Such legislative decisions are inimical to the norm of impartial government.
The mandate of impartiality also constrains those state actors who implement state laws. Thus, the Equal Protection Clause would have been violated in precisely the same manner if in Reed there had been no statute and the probate judge had simply announced that he chose Cecil Reed over Sally Reed “because I prefer males to females.”
Appellant does not contest the vital importance of those ends to the people of New York. It has long been accepted that illegitimate children whose parents never marry are “at risk” economically, medically, emotionally, and educationally. See E. Crellin, M. Pringle, & P. West, Born Illegitimate: Social and Educational Implications 96-112 (1971); cf. T. Lash, H. Sigal, & D. Dudzinski, State of the Child: New York City II, p. 47 (1980).
In Caban, the Court noted that an adoption “may proceed in the absence of consent when the parent whose consent otherwise would be required . . . has abandoned the child.” 441 U. S., at 392.
Appellant also makes an equal protection argument based upon the manner in which the statute distinguishes among classes of fathers. For the reasons set forth in our due process discussion, supra, we conclude that the statutory distinction is rational and that appellant’s argument is without merit.