The argument that made gay marriage law in America was about marriage equality: not special rights for gay people but the right to the same treatment. There may be something to regret in the smallness of this ambition (previously), but the argument is sound.
Denying people the right to marry requires a public justification -one that would be in principle convincing to all concerned - and this demands more than the expression of the private moral beliefs of a politically dominant group like fundamentalist Christians. What this comes down to is the moral and political significance of the challenge Why not? for public reasoning in a liberal society, for identifying and overturning unjust laws and policies.
In the wake of the US Supreme Court's decision it is therefore rather disconcerting to find various gay marriage advocates, most notably, Jonathan Rauch, arguing so badly - basically sneering - against polygamy. One has the impression of a drawbridge being raised up. As far as I can tell, polygamy presents as good a case as gay marriage for legal recognition and regulation by the state, as Justice Roberts' Supreme Court dissent pointed out.
Many arguments against polygamy depend on widely shared prejudices about its contemporary practice. It is defined by its portrayal on TV reality shows, with some 3rd hand references to illiberal patriarchal societies in the Middle East or fringe fundamentalist Mormon communities and underage marriage.
The parallels with the ignorant disgust with which homosexuals were once perceived - and still are outside the West - is striking. Our experience of overcoming that prejudice should inform our response to this one.
Some want to draw a line between gay marriage and polygamy "because people aren't born polygamists", as the political satirist Jon Stewart put it to loud applause. The logic of this is disturbing.
It implies that homosexuals are defined by a congenital medical condition and the rest of society should take pity on them for this and try to arrange some special accommodation of their special needs so that they can live a facsimile of a normal life. As if they were physically disabled and asking for wheelchair access to public transport rather than protesting against the restrictions on their lives that the government itself imposed.
It is also inconsistent with the structure and success of the argument for marriage equality. In a liberal society, people do not have to justify their difference. It is the people who want to impose different treatment upon them who must justify themselves.
The public justifications that I have seen proposed for maintaining a ban on polygamy are ridiculous or appalling. Rauch for example argues that polygamous societies are bad for gender equality and are rapey violent places where lots of men are excluded from the benefits of marriage.
First, why suppose that a society that legalised polygamy would become a polygamous society? Is it really only the ban which is keeping us all from making the switch to polygamy? (Will the legalisation of gay marriage turn us all gay, as some conservatives seemed to claim it would?)
In any case, why make that presumption the test for a law? In a liberal society, why should the political right of these individuals to live their own lives as they see best be subject to an ethical (rather Kantian) test of 'What if everyone did that?' This is not a test we require of other groups. The gay rights movement itself, let alone gay marriage, would not have passed it. Consider, 'What if everyone only had sexual relationships with people of the same sex?' Society would die out (absent extensive technological intervention).
A liberal society does not place the burden of maintaining social well-being upon individuals in this way. And it does not define social well-being in terms of loyalty to traditional institutions and values in the first place. In a liberal society people should be as free as possible to pursue a life they consider worth living and to experiment with different forms of life. Social well-being actually benefits from the consequent disruption of social harmony by spontaneously evolving social norms, as in the case of women's rights.
Second, the assumption that polygamy is necessarily a patriarchal system prone to the abuse of women, especially children is not reasonable. Consider the historical transformation of monogamous marriage from the legalised male despotism described by JS Mill to the somewhat egalitarian institution of today. If monogamy can evolve with liberal society and become civilised by laws and social values that protect gender equality, why can't polygamy?
Fairness requires that proponents of polygamy be treated with equal respect. They deserve counter-arguments that are coherent and consistent with values asserted elsewhere, not ad hoc rationalisations for private prejudice in the style of the rhetoric of reaction. No, claiming the right to marry two people you love is not the same as asking to marry your toaster and is not in the same category as date-rape.
Rauch goes so far as to say that since people are not legally prevented from having multiple sexual relationships at the same time there is no pressing need to recognise polygamous marriage. (One wonders why he advocated gay marriage then.)
On the contrary, just as for gay marriage, legal recognition would counter discrimination, provide access to ancillary legal rights, and permit regulation.
It is pretty obvious that polygamy is the object of general contempt and derision. That's why opponents of gay marriage used it as an example of the pit at the bottom of the slippery slope. This contempt is partly sustained by the state's refusal to acknowledge any value in this way of living. While legal recognition alone would not confer popular approval, legalising polygamy would confer formal equality and dignity. As when the Supreme Court overturned bans on mixed-race marriage, it would provide a platform for further campaigning for social recognition and equality. Those who denigrate polygamy would be on the back foot - the onus would be clearly on them to justify their disdain rather than on polygamists to justify their difference.
There are thousands of ancillary rights associated with legal marriage, from next of kin rights for hospital visits to inheritance tax laws. If these rights follow from the recognition of the special value and practical importance of long-term committed romantic relationships in the lives of adults then there is no good reason to limit them to monogamous relationships. Monogamy does not have a monopoly on loving mutual commitment. Restricting these rights makes the lives and loves of polygamists unnecessarily difficult, and this appears quite deliberate. The state has effectively used its authority to privilege a particular form of romantic love that reflects the private prejudices of the majority, and is using its bureaucratic powers to make it difficult for people to live in any other way.
Finally, polygamy would benefit greatly from state regulation. The best way to protect the rights of polygamists within marriage is to bring it within the law, where the rights of women and children can be protected in line with secular liberal moral standards.
For example, polygamy should be legally construed as group marriage, where each adult is married to every other. This arrangement protects the rights of all parties and is morally superior but still consistent with traditional hub-and-spoke polygamy, where one man might marry several wives one after another even if the first wife would prefer otherwise. It is consistent because giving people the right to exercise a veto doesn't force them to use it, and it is morally superior because it makes submissive gender roles an individual choice rather than an institutional fact. (Just as modern monogamous marriage does not prevent arranged marriage but does prevent forced marriage.)
For another example, legalising polygamous marriage would also legalise polygamous divorce. Many marriages fail and when they do the parties need to be able to solve their differences within an equitable and adequate legal framework. Otherwise the division of property and children will be driven by bargaining power alone, something long recognised as a problem with traditional monogamous marriage. The fact that polygamous divorce may be particularly complicated only makes it more important to develop an adequate legal framework for it.
I had always thought that I was against the legalisation of polygamy. Yet reading the arguments against it from so called progressives in the wake of the US Supreme Court's ruling has changed my mind. When the challenge - Why not polygamy? - is explicitly put, it seems there is no answer to be had but a barrage of bigotry and sneers.