4.3 Same-Sex Marriage

The proposal to replace marriage entirely with civil unions or domestic partnerships differs from the ‘compromise’ proposal of a two-tier marriage law: marriage for opposite-sex couples only, and civil unions or domestic partnerships for same-sex and, if they choose, opposite-sex couples. The compromise proposal grants some of the benefits of marriage without ceding the title (or indeed, as usually proposed, all the benefits) of marriage to same-sex couples. This position does not fully answer arguments for same-sex marriage.

Many arguments for same-sex marriage invoke liberal principles of justice such as equal treatment, equal opportunity, and neutrality. Marriage provides benefits which are denied to same-sex couples on the basis of their orientation; if the function of marriage is the legal recognition of loving, or “voluntary intimate,” relationships, the exclusion of same-sex relationships appears arbitrary and unjustly discriminatory (Wellington 1995, 13). Same-sex relationships are relevantly similar to heterosexual relationships recognized as marriages, yet the state denies gays and lesbians access to the benefits of marriage, hence treating them unequally (Mohr 2005, Rajczi 2008, Williams 2011). Further, arguments in support of such discrimination seem to depend on controversial moral claims regarding homosexuality of the sort excluded by neutrality (Wellington 1995, Schaff 2004, Wedgwood 1999).

To see why a two-tier solution fails to address these arguments, we must consider what benefits marriage provides. There are tangible benefits such as eligibility for health insurance and pensions, privacy rights, immigration eligibility, and hospital visiting rights (see Mohr 2005, Chapter 3). Crucially, however, there is also an important benefit of legal, and indirectly social, recognition of a relationship as marriage. The status of marriage itself confers legitimacy and invokes social support. The two-tier system does not provide equal treatment because it does not confer on same-sex relationships the status associated with marriage.

In addition, some philosophers have argued that excluding gays and lesbians from marriage is central to gay and lesbian oppression, making them ‘second-class citizens’ and underlying social discrimination against them. Marriage is central to concepts of good citizenship, and so exclusion from it displaces gays and lesbians from full and equal citizenship: “being fit for marriage is intimately bound up with our cultural conception of what it means to be a citizen … because marriage is culturally conceived as playing a uniquely foundational role in sustaining civil society” (Calhoun 2000, 108). From this perspective, the ‘separate-but-equal’ category of civil unions retains the harmful legal symbol of inferiority (Card 2007, Mohr 2005, 89, Calhoun 2000, Chapter 5; cf. Stivers and Valls 2007).

However, if marriage is essentially heterosexual, excluding same-sex couples is not unequal treatment; same-sex relationships simply do not qualify as marriages. One case for the essential heterosexuality of marriage invokes linguistic definition: marriage is by definition heterosexual, just as a bachelor is by definition an unmarried man (Stainton, cited in Mercier 2001). But this confuses meaning and reference. Past applications of a term need not yield necessary and sufficient criteria for applying it: ‘marriage’, like ‘citizen’, may be extended to new cases without thereby changing its meaning (Mercier 2001). As noted above, appeal to past definition begs the question of what the legal definition should be (Stivers and Valls 2007).

A normative argument for the essential heterosexuality of marriage appeals to its purpose: reproduction in a naturally procreative unit (see 3.2.a). But marriage does not require that spouses be able to procreate naturally, or that they intend to do so at all. Further, married couples adopt and reproduce using donated gametes, rather than procreating ‘naturally’. Nor do proponents of this objection to same-sex marriage generally suggest that entry to marriage should be restricted by excluding those unable to procreate without third-party assistance, or not intending to do so.

Indeed, as the existence of intentionally childless married couples suggests, marriage has purposes other than child-rearing—notably, fostering a committed relationship (Mohr 2005, Wellington 1995, Wedgwood 1999). This point suggests a second defense of same-sex marriage: exclusive marital commitments are goods which the state should promote amongst same-sex as well as opposite-sex couples (Macedo 1995). As noted above, such rationales come into tension with liberal neutrality; further controversy regarding them will be discussed below (5.2).

Some arguments against same-sex marriage invoke a precautionary principle urging that changes which might affect child welfare be made with extreme caution. But in light of the data available, Murphy argues that the precautionary principle has been met with regard to harm to children. On his view, parenting is a basic civil right, the restriction of which requires the threat of a certain amount of harm. But social science literature shows that children are neither typically nor catastrophically harmed by same-sex parenting. Even if two biological parents statistically provide the optimal parenting situation, optimality is too high a standard for permitting parenting. This can be seen if an optimality condition is imagined for other factors, such as education or wealth (Murphy 2011).

A third objection made to same-sex marriage is that its proponents have no principled reason to oppose legalizing polygamy (e.g. Finnis 1997; see Corvino 2005). One response differentiates the two by citing possible harmful effects for women found in male-headed polygyny, but not in same-sex marriage (e.g. Wedgwood 1999). Another response is to bite the bullet: a liberal state should not choose amongst the various ways (compatible with justice) individuals wish to organize sex and intimacy. Thus, the state should recognize a diversity of marital relationships—including polygamy (Calhoun 2005, Mahoney 2008).

Finally, some arguments against same-sex marriage rely on judgments that same-sex sexual activity is impermissible. As noted above, the soundness of these arguments aside, neutrality excludes appeal to such contested moral views (Rawls 1997, 779, Schaff 2004, Wedgwood 1999). However, some arguments against same-sex marriage have invoked neutrality, on the grounds that legalizing same-sex marriage would force some citizens to tolerate what they find morally abhorrent (Jordan 1995). But this reasoning seems to imply, absurdly, that mixed-race marriage, where that is the subject of controversy, should not be legalized. A rights claim to equal treatment (if such a claim can support same-sex marriage) trumps offense caused to those who disagree; the state is not required to be neutral in matters of justice (Beyer 2002; Boonin 1999; Schaff 2004; see also Barry 2011).