From the infuriatingly libertarian, but consistent, Richard Epstein of the University of Chicago Law, a column in Forbes on Prop 8, and why the answer is to de-regulate marriage from any government licensing:
Today's harsh skirmishing over Prop 8 starts from the common assumption that the state has the right to issue marriage licenses, so that the only question worth asking is whether it can discriminate between gay and straight couples. But to the libertarian, the antecedent inquiry is whether the state has any proper role in issuing marriage licenses at all.
Historically, people married long before the state issued its licenses. As with all licenses, the libertarian demands that the state justify any restriction on individual choice. By what warrant does the state regulate marriage? Not to protect children, who need as much protection against single parents as against married couples. For that end, use laws prohibiting abuse or neglect that are tied to child custody, not marriage.
More seductively, defenders of Proposition 8 insist that it is needed to "protect" marriage. From what? Surely not against threats of force designed to prevent couples from getting married. Unfortunately here, the "protection" is not against force, but against competition. That protection is no more legitimate than using high tariffs walls to protect American producers against foreign competition.
Truth is that free entry works in both cases. It is no business of the state to prohibit relationships that offend others' deeply held beliefs….
Sound political theory offers no haven to the defenders of Proposition 8. Unfortunately, constitutional law treats them more kindly. The California Court ignored the brute historical truth that our constitutional guarantees of individual liberty were always subject to a "police power limitation" on matters of health, safety, morals and general welfare. The libertarian is comfortable with laws that protect against contagion or explosion, but decidedly not with the historical conception of morals…
It was therefore risky business for gay-rights advocates to push the constitutional button that exposed them to the counterattack of Proposition 8. …