folk1e asks: "What about the pluralistic marriages undertaken in similar circumstances?"

Well, I live in Nevada which has a very substantial population of Mormans, and they are not allowed multiple partners. It has been against church policy for a long time, and it is against the law. There are a number of men serving prison time right now who simply married more than once.

If we use Bill D's standard that it does not affect the lives of others, then clearly these people should not be in any trouble.

If gay unions become recognised by the government as equal to heterosexual ones, polygamy must also be recognized as equal.