This ability to be named on a birth certificate as a co-parent (or, as we used to call it, "mother" and "father") has important legal consequences and cannot be dismissed as mere quibbling over semantics. Allowing a spouse to be entered on the birth certificate as a parent traditionally conveys parental rights and responsibilities to the party so named. Conversely, requiring a spouse to adopt the child to claim parental rights requires significant expenditure of time and money and serves as a significant barrier to entry.
I come to no conclusion. The problem is a novel one, and rests on a premise that is out of fashion -- that biological differences between people may be relevant to the definition of rights. All I can say is that, from a legal perspective, I wish they would hurry up with an artificial replicator as seen in the Vorkosiverse. It would make things much tidier.
Back in old, old days, by which I mean immediately after WWII, marriage was only between a man and a woman and concepts like "wedlock" mattered for actual legal things -- such as defining inheritance rights. Paternity also mattered, regardless of wedlock, for certain legal consequences. But while maternity was usually easy to establish by being present for the event, paternity was not subject to proof. A man might impregnate a women to whom he was not married, or a woman married to a man might conceive from another man. As these things mattered for social reasons and for establishing legal rights, certain legal presumptions existed.
Of relevance, the law presumed that if a woman was married, that the man married to her was the father. this held even under circumstances where the allotted time from marriage to birth would preclude conception during marriage. If you tied the knot before the baby popped out, it was presumed the legitimate child of the fellow who gave you the wedding ring. Rebutting this presumption after the fact to avoid the consequences of being a father was usually difficult, if not impossible. Being listed on the birth certificate as Daddy made you legally Daddy, with all the rights and responsibilities attendant thereto. While this presumption had lots of exceptions in practice, it was as good as any other legal presumption to resolve doubt ever is.
In cases of a divorced or widowed biological parent remarrying, it was clear that the new parent was not biologically related to the child. In this case, the new spouse would have to formally adopt the child. As this had the effect (back then) of entirely eliminating the biological parent's rights, it was not undertaken lightly. In those days, we were rather rigid on a child having one Mommy and, ideally, one Daddy. As children were wards of their parents and generally treated as entailed chattel (they could not be sold, but you could whup them like stubborn mules if they misbehaved), it was considered important to have clear, unambiguous sets of rights and responsibilities.
So, to summarize, we start for the purposes of our story with a legal presumption that a family consists of biological Mommy, biological Daddy and Children as the set of cognizable legal interests. Since we cannot always prove biological Daddy, the law makes a presumption that biological Daddy is the guy married to biological Mommy. Where it is certain that there is no biological relationship, the law does not recognize a parental interest absent adoption, which eliminates the rights of the parent(s) so replaced.
Time passes, social patterns proceed to change. We have a lot more children born out of wedlock, both to single moms and moms in combinations that are not traditional marriage. We have a trend to avoid entirely terminating the rights of birth parents, particularly mothers, via adoption. We have significant shifts in divorce and custody, and other shifts in family patterns. All of these work to undermine what had previously been considered the previous underlying assumptions wrt to who is considered a child's parent and what level of legal interest in a child the law acknowledges and protects.
Put another way, first society, then the law, begins to view family and family rights as a social construct rather than as a limited set of biological rights. More accurately, the law begins to recognize social interests in the construction of the family overlayered with biological rights. This is particularly true for the rights of biological mothers, in large part owing to a convergence of cultural prejudices from both the liberal and conservative elements of society. As a result, a biological mother's rights are no longer entirely eliminated by adoption. But we also extend certain family rights (in some jurisdictions) to grandparents, to domestic partnership arrangements that are not traditional marriage, and to others in a not entirely consistent pattern.
Most recently, the rise of the idea of the family as social construct free from biological determinant has given rise to first the idea, then the actuality, of same sex marriage. This is the natural continuation of the idea of family as social construct, in which the primary purpose is the fulfillment of the needs of the individuals, rather than as a biological unit designed primarily for propagation of the species and accumulation of physical wealth and social capital. In particular, society begins to move from seeing marriage as a desirable pre-requisite for engendering children (in part so we can be more certain of paternity for economic and social reasons) to seeing marriage (or other forms of family) as a desirable pre-requisite for raising children (no longer regarded as entailed chattel to their biological parents) in a nurturing environment. It is on this basis that the Massachusetts Supreme Judicial court found no "rational basis" for defining marriage as solely between a man and a woman.(Although why we exclude polyamoury is unclear, but social evolution is invariably a gradual process.)
But this now creates an interesting conflict between the old presumptions, which made biological relationship with the child the defining factor, and the new presumption of marriage as social construct. The person married to the biological mother of a child at the time of birth is presumed to be the child's father. But this presumption was based on biological likelihood, and was rebuttable under certain circumstances. Where we could know with certainty that the spouse of the biological mother (or father) was not biolgically related to the child, such as in the case of a second marriage following divorce, we require adoption. (Or, as Nick Naylor, anti-hero of Thank You for Smoking says to his ex-wife's husband, "Brad, I'm his *father.* You're just the guy [having sexual relations] with his Mom.")
Which brings us to the current decision of NY State, and now NYC, to allow a woman married to another woman giving birth in a NY hospital to enter the name of her partner on the birth certificate as co-parent. On the one hand, this would appear to be a useful extension of the "family as social construct" rule, in that it extends the traditional presumption that the person married to the birth mother is the father. If we view this as a privilege attendant upon marriage, then it is logical to extend all privileges of marriage, including the right to the presumption of "fatherhood" to the non-birthing spouse.
But viewed another way it makes no sense, because we know that the woman married to the birth mother is not a parent of the child. We not only know this, we know that it cannot be true. While it was certainly factually true often enough that the man married to the woman giving birth was not the biological father, and that in individual cases we could know this with certainty, it was a useful legal presumption that was true often enough that we could ignore the cases where the presumption was wrong as irrelevant. Furthermore, if the presumption later proved false, it might be rebuttable for certain purposes.
But here in absolutely all cases of a woman married to a woman, we know the non-birthing woman is not the biological parent. We know it as assuredly as if the couple were married after the birth of the child, and it is true for every case of such a pairing until medical science advances. This not only creates an absurd result -- that the difference of timing in marriage makes the difference between adoption and recognition as co-parent (a factor which was not the case under the old rule where it was a mere presumption) -- but a discriminatory impact. it creates a class of people, married men, who can never be co-parents except though adoption.
But there is an underlying reality. The child has a second biological parent other than the biological father, who is determinable with certainty at the moment of birth. The fact that she is not married to the biological father is not legally determinitive. Like Stan in life of Brian who wants to have babies but can't, two married men cannot enjoy the same ease of becoming co-parents as two married women.
So wherein does equal protection lie? Should we treat marriage to the birth mother as giving rise to the right to claim co-parency? On what grounds? Because it arises from a now defunct legal presumption that we chose to treat as a right attendant on marriage? If it is because marriage is a social construct, we should extend the right to married men. But married men do not have the same factual situation as married women, in that there is an actual birth mother somewhere that the law traditionally cares about.
Shabbos requires that I stop here. But it raises fascinating questions for consideration.