Legal prohibitions on incestuous marriage (be they first-cousin marriages or on the monstrousity that would be sibling marriages) are an important part of the argument that there is no constitutional right for any two people to get married to each other. However, to the extent that first-cousin marriages in which one of the parties is infertile are exempt from the marriage prohibition (as is the case in the MD bill), we would be back in square one, since same-sex-marriage proponents would point out that same-sex “marriages” don’t produce offspring, either.
‘same-sex “marriages” don’t produce offspring, either.’
Yeah, but now they’re allowed to pollute perfectly normal children, anyway, to make up for it.