https://c4ss.org/content/38464
"Let’s get something out of the way at the start: the state — even if it should exist — should not be involved in marriage. But libertarians who think that this is all that need be said are wrong. To see this, imagine that the government declared that blacks could not use the interstate highways. Would it be enough for libertarians to say that the government should not own and operate highways, remaining agnostic on the particular policy? Of course not, because that’s not all there is to the matter. Libertarians should say that as long as the government does own and operate highways, it must not discriminate irrationally or invidiously in their use. Why is that a proper libertarian position? It is so because libertarians, pending abolition of the state, should want to limit as far as possible its power to commit injustice, to mistreat people or deprive them of their dignity. One way to do that is to eliminate or at least restrict its power to discriminate irrationally or invidiously. Government should not have the power to issue marriage licenses, but when it exercises that power, it should not be free to deny them to gay and lesbian couples. On what libertarian grounds should same-sex couples be turned away from the licensing bureau? As Steve Horwitz writes: “Classical-liberal principles require the State to treat all citizens as equal before the law.” This, he notes, has been one of the aims of liberal movements from time immemorial. Horwitz writes:
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It does not follow, as some libertarians suggest, that under the equality principle, laws that burden one group ought apply to all. The principle is equal protection. If the government imposed conscription on men, it would be unlibertarian to demand that women also be drafted in the name of equality under the law. On the contrary, that principle would be grounds for demanding abolition of conscription.
I’ve seen it argued that if marriage consisted merely in “negative rights” — rights, that is, against aggression — a libertarian could have no objection to legalization of same-sex marriage. But, the argument goes, since contemporary marriage entails “positive rights” as well — that is, (alleged) “rights” to government-provided benefits — a libertarian should object to extending this tainted institution to more people. That argument seems plausible at first, but I believe it crumbles on closer scrutiny.
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Let’s take an example, the federal Family and Medical Leave Act, which requires employers to provide job-protected though unpaid leave for qualified reasons. (Some states have similar laws.) Since passage of the law in 1993, FMLA benefits have been extended by the courts to same-sex couples who married in a state that recognizes that status.
Now it is true that mandated family and medical leave coercively imposes costs on employers (and ultimately employees) and therefore cannot pass libertarian muster. It is also true that with this latest Supreme Court decision, FMLA benefits will now apply to more people. But contrary to some libertarians, that is no reason to condemn the Supreme Court’s decision. Rather, it’s simply a reason to work for the repeal of the FMLA. Allowing the prohibition of SSM in order to prevent expansion of the FMLA is a little like bombing a village full of innocents to kill a criminal. To avoid one harm, a great deal more harm would be done. And note: it is not married couples who compel employers to provide leave, even if they take advantage of the law. The state is the aggressor. Let’s go after it and its impositions directly. Discriminating against same-sex couples does nothing to end those impositions. It simply declares that the benefits are for heterosexual couples only."