The resignation of California's Rep. Katie Hill, involving allegations that she was involved in a three-way sexual relationship, and an ensuing succession of articles defending polyamorous relationships, has National Review's John Hirschauer wondering whether polygamy will be the next frontier in the redefinition of marriage.

Just this week, CBS News ran a story about the "stigma of consensual non-monogamy," which complained: "There is no legal framework for polyamorous families to share finances, custody of children or the rights and responsibilities that come with marriage.  Likewise, there are no legal protections against people facing discrimination for being in a non-monogamous relationship."

The legalization of polygamy is not likely to happen any time soon, but the groundwork has already been laid.

In his brilliant book Marriage and Civilization: How Monogamy Made Us Human, William Tucker persuasively argued that monogamy created the conditions for the flourishing of human civilization.  This is the view accepted by religious Christians, of course, but Tucker made his case for the traditional family on secular grounds.

Noting that the disintegration of the family unit has been a major contributor to poverty, "the rule is: those who form traditional families succeed; those who don't fail."  Monogamy isn't a "natural" institution, Tucker cautioned; it requires the underpinnings of culture.  To sustain itself, monogamy "requires rules — rules that must be continuously enforced by the members practicing it."

Interestingly, Tucker was agnostic on the issue of same-sex "marriage," even positing that "if gay people aspire to monogamous marriage that only enhances its place in society."

However, he added the following important caveat:

The important thing for supporters of same-sex marriage [sic] is to draw a stark line between acceptance of gay marriage [sic] and acceptance of an 'anything-goes' attitude toward marriage, which says that it makes no difference whether people tie the knot or live in sin, whether they marry a man and a woman or marry two wives or three wives (because polygamy is always lurking at the edge of these discussions), or whether they marry their dog or their cat or their favorite lampshade." [p. 8]

Unfortunately, supporters of gay "marriage" were never required to articulate such a distinction, because the next year, the Supreme Court decided Obergefell v. Hodges, which held that same-sex "marriage" is a constitutionally protected right.  Until federal courts intervened, the issue was being debated by the people through their state legislatures.  A robust debate that might have clearly delineated the difference between allowing same-sex "marriage" and allowing polygamy was short-circuited.

In his dissent, Chief Justice John Roberts anticipated the issue of polygamy:

Although the majority randomly inserts the adjective 'two' in various places, it offers no reason at all why the two-person element of the core definition of marriage may be preserved while the man-woman element may not. Indeed, from the standpoint of history and tradition, a leap from opposite-sex marriage to same-sex marriage [sic] is much greater than one from a two-person union to plural unions, which have deep roots in some cultures around the world.

"It is striking," the chief justice concluded, "how much of the majority's reasoning would apply with equal force to the claim of a fundamental right to plural marriage."

As Hirschauer noted, Justice Anthony Kennedy's majority opinion in Obergefell "uses a nebulous, inchoate definition of marriage predicated on poetic notions of 'dignity' and 'love' rather than the traditional, unbroken consensus of Western civilization.  Why would the Court find the traditional restriction of marriage to a union between two persons a compelling reason to withhold the right to marry from three (or more) claimants?  If 'love,' 'dignity,' and the pursuant tax advantages are the constitutive parts of marriage, on what grounds would ... the courts withhold those 'rights' from polygamous unions?"

With a firm, but slim, conservative majority on the Court, the slippery slope of Obergefell isn't likely to lead to legal polygamy just yet.  But a challenge will come.  It may come from "lifestyle" polyamorists seeking the benefits of marriage.  Or it may come from the growing numbers of immigrants coming to the United States from countries in Africa and the Middle East, where polygamy is legal.  Either way, conservative jurists had better be ready to meet that challenge.

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