In general, courts legitimately may use some extra-textual sources to determine whether a claimed inalienable right exists. Debatable issues, instead, include the appropriate types and relative weights of those extra-textual sources; the ways to apply them to articulate rights without undue judicial discretion; and conclusions that should follow from applying those sources and methods about the existence, nature, and scope of rights protected--all still difficult, remaining questions.
Public debate about abortion also illustrates the distinction between fair and irrelevant issues for argument. A genuine critique of Roe (refined by Casey) cannot merely complain the text lacks the term "abortion." And basic reproductive freedom and women's bodily autonomy at least reflect principled implications of Griswold, other precedent, and text--even if one contests the formulation and application of those principles. Most legitimately disputable is the competing scope of states' asserted interests in pregnant women's health and fetal "life," the rationale allowing states to ban most abortions after fetal viability. Genuine debate continues on the nature and limits of those interests and their relation to a woman's rights.
Conservative: Granted there are unenumerated rights, but declaring a right to control procreation displays too much discretion by judges.
Whole Constitutionalist: The Court recognized women's reproductive and bodily autonomy in a process yoked to text, history, and precedent. At the same time, it has recognized states' interest in the fetus, allowing bans of most post-viability abortions --following a common law, rather than either a religious or secular-moral, view of whether and when fetal "life" becomes comparable to born human life.
Freed from the obfuscation of myth-based thinking, the above dialogue could continue productively. (Note Conservative's interlocutor is now Whole Constitutionalist, reflecting this essay's perspective.)
The whole-constitutionalist perspective on gay rights.
Attuned to the Court's approach to such other rights issues, gay marriage advocates present two independent constitutional arguments. The first relies on more-explicit text, the Equal Protection Clause: "No state shall . . . deny to any person within its jurisdiction the equal protection of the laws." On its face, that text could be read to prohibit states from denying gays a legal right afforded heterosexuals--the right to choose a marriage partner corresponding to one's sexual orientation.
But equal protection precedent calls for a more-constrained analysis. To uphold most classifications that treat groups of people differently, the Court has required only a rational basis. Thus, the class of speeding drivers can be made to pay a fine others do not because highway safety is a legitimate government goal to which such fines are rationally related. The government has been required to meet a higher level of justification, heightened scrutiny, only for certain classifications: those related to the Equal Protection Clause's original motivation--racial classifications--and those of certain other groups who have been held to somehow have diminished political power.
The Court has held just four non-racial classification types require justification greater than mere rationality: nationality, alienage (with exceptions), gender, and being born to unmarried parents. Paralleling the conservative turn in its composition, the Court has not identified any further "suspect" classifications since the 1970s, rejecting heightened scrutiny for classifications based on, for instance, age, disability, and wealth. The Court even rejected sexual orientation as a suspect classification in 1986, upholding a conviction for homosexual sodomy in Bowers v. Hardwick, finding Georgia rationally determined to treat same-sex sexual activity differently.
But two subsequent decisions cast doubt on Bowers's continuing validity. In Romer v. Evans, the Court overturned a Colorado constitutional amendment that prevented municipalities in the state from enacting ordinances to prohibit sexual-orientation discrimination. And Lawrence v. Texas struck down a homosexual sodomy law. In neither case, however, did the Court call sexual orientation a "suspect" or "quasi-suspect" classification--one requiring some form of heightened scrutiny. Rights advocates had argued for "intermediate scrutiny"--a test already applied to classifications based on gender and birth to unmarried parents--requiring government to show its actions to be substantially related to an important government interest. Overturning both states' provisions, Justice Kennedy instead characterized them as either (i) based on the illegitimate motivation of animus towards gays or (ii) not rationally related to any other governmental objective that is legitimate. But most scholars, as well as Justice Scalia in his Lawrence dissent, recognized that the threshold for justification Kennedy actually employed was higher than the typical "rational basis" test, much more like intermediate scrutiny. Many commentators characterize Romer, Lawrence, and a few similar cases as applying a "rational basis plus" test, an unclear standard, uncertain in application. If the Court reaches the merits of the present appeals, it could clarify the standard for gay rights.
Bans on same-sex marriage probably fail the most-likely clarified standard, intermediate scrutiny. Opponents have not established any important governmental purpose gay-marriage bans directly and substantially relate to achieving. By contrast, empirical evidence shows they do not enhance the stability of heterosexual marriages or welfare of children.
The alternative to the equal protection argument relies on the more-generally-framed Due Process clauses restricting both the federal and state governments. Again, the Court uses the prohibition against denying "life, liberty, or property without due process of law" as the starting point for articulating unenumerated fundamental rights, holding the states to be restricted by almost all the concepts that expressly limit the federal government in the Bill of Rights. And both the federal and state governments are restricted by other unenumerated rights, such as those to contraception and abortion. The due process analysis would consider the claimed right to marry the adult partner of one's choosing against that backdrop of a wide range of already-recognized, unenumerated rights, aided by general, limiting principles that guide the determination of whether any claimed right is inalienable.
For heterosexuals, precedent does already recognize an adult's right to marry--to enter into a legally-significant, intimate, family-enabling, indefinitely-enduring commitment to any adult of the sex to which they are primarily attracted--even if genetics place them in a racial category different than their chosen partner's.
Absent some principled reason all Americans do not share that right, then, every adult is fundamentally entitled to enter into that legally-significant, intimate, family-enabling, indefinitely-enduring commitment to an adult of the sex to which they are primarily attracted--even if genetics or other formative elements have placed them in the sexual-orientation minority. And that children raised by gay couples are not their joint genetic issue is not a distinction that justifies denying their rights; heterosexual couples are fundamentally entitled not to procreate at all and can raise non-joint-genetic children. What's more, the Court has already held that all Americans may believe anything, say almost anything, associate with almost anyone, and worship in almost any way, even not at all. A same-sex marital spouse also constitutes an associational choice and exercise of fundamental personal beliefs and practices.
And the scope of unenumerated rights cannot be limited to a narrow conception of American "tradition." Court conservatives often argue the constitutional significance of tradition--for instance that it justifies both limiting fundamental parental rights to marital partners, not unwed fathers, and extending gun rights beyond what the Second Amendment requires. Yet our tradition also includes slavery, and we inherit the practice of opposite-sex marriage from eras when people were severely oppressed for being gay. A more-Burkean view scrutinizes tradition for embedded values still relevant. The contemporarily-relevant value in the "marriage tradition" is not anti-gay prejudice but the virtue of committed adult relationships. And embedded within tradition supporting many other recognized rights are more-general values of freedom of thought, association, and life-style choice, also supporting marital choice. Kennedy's Lawrence opinion spoke of the rights of intimate association between consenting adult partners in the privacy of the home; the ability to legally commit to one's partner in such a relation seems just as fundamental, just as traditional. (And fi nding a right to same-sex marriage would not also constitutionalize polygamy. As rejecting plural marriage does not deny anyone a committed relationship with an adult of the sex to which one is attracted, limiting one to a single marital partner at a time does not offend the fundamental right that supports gay marriage.)
Finally, t hose who argue the infringement on marriage rights to be insubstantial because civil-unions suffice for gays harken to the narrow thinking of 1896, the "separate but equal" specter of Plessy v. Ferguson. Fifty-eight years later, the Court rejected that concept in Brown v. Board of Education, following extensive empirical evidence not only that purportedly-equal conditions generally prove far from equal when scrutinized, but that other, intangible harms inevitably inhere when we separate citizens using immutable characteristics.