An Economic Assessment of Same-Sex Marriage Laws – Harvard Journal of Law & Public Policy

It is a complex set of personal values, social norms, religious customs, and legal constraints that regulate a particular intimate human relation over a life span … [M]arriage has always entailed more than a mere “contract.” Marriage involves not just a couple, but extended family members, non-blood relations, and impersonal third parties like the church, state, or tribe. … [M]arriage is an institution uniquely equipped to handle incentive problems between a man and a woman over their full life cycle. …

The economic case against same-sex marriage, based on new institutional ideas, is that it is likely a bad idea for both heterosexual and homosexual couples. …

This Article argues that the institutional details of marriage are designed with specific purposes in mind, and that these purposes generally have little to do with homosexual relations. The fundamental point of this Article is that when different human relationships fall under a “one size fits all” law, the result is a bad fit for everyone. Alterations to heterosexual institutions resulting from contracting problems arising in homosexual relations will have profound effects on heterosexual marriage, and heterosexual pressures on marriage law will likely be inappropriate for homosexual couples. The problem with having a set of laws that does not provide a good fit for the couple is the ultimate effect such laws will have on children. Marriage stability is often sensitive to changes in the law, with greater divorce rates a common outcome. The effects of divorce are often ambiguous on the husband and wife, but for children they are mostly negative.”

http://www.law.harvard.edu/students/orgs/jlpp/Vol29_No3_Allen.pdf