Sherif Girgis, Ryan Anderson and Robert George: Does Marriage Have Essential Properties?

…in attempting to explain away the parallel Western legal tradition,…[Andrew Koppelman] does concede that the original public purpose of marriage law was not to oppress or exclude anyone, but to ensure that wherever possible children were reared by their father as well as their mother. His contention is simply that we should now expand its purposes to recognize same-sex partnerships.

Note two things about this concession.

First, it shows that when Koppelman insists that “any definition of marriage that excludes same-sex couples strikes [him] as already underinclusive,” he is simply measuring marriage law against a set of purposes that, for whatever reasons, he wishes it served, and not against the purposes that he admits it has served historically. In other words, Koppelman seems implicitly to concede that there is a rational basis for current marriage law””in which case, it passes constitutional muster. He also implicitly concedes that to recognize same-sex partnerships would be not merely to expand but to change the definition and meaning of civil marriage.
Second, while urging that we expand marriage law’s understood purposes, Koppelman says nothing to answer a consideration we raise against doing so: If the law encourages people to see marriage as an essentially emotional union that has no principled connection to organic bodily union or procreation, then marital norms (e.g., permanence, exclusivity, monogamy) will increasingly be treated as optional at best, and groundlessly restrictive at worst””at great cost to children and society generally. (After all, there is no reason that essentially emotional unions like friendships should involve pledges of permanence or exclusivity.) Koppelman also completely sidesteps our specific argument that he has no ground of principle for opposing “open marriages” and legal recognition of polyamorous sexual partnerships as marriages….

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