Slow news day over at the National Review, which asks the question "Is a lesbian threesome any less legitimate than a lesbian twosome?"
Let's dissect that question.
Were the question to ask only "Is a lesbian threesome less legitimate than a lesbian twosome?" there wouldn't be a problem. It's a simple question with a simple answer. From a legal standpoint, yes, a lesbian threesome is less legitimate than a lesbian twosome because civil marriage is limited to two persons. Similarly, the question "Is a lesbian threesome any less legitimate than a mixed-gender threesome?" is easily answered. From a legal standpoint, no, the law does not presently permit more than two people to be married concurrently.
However, as asked, "Is a lesbian threesome any less legitimate than a lesbian twosome?" starts from the premise that a lesbian twosome (presumably referring to a married couple comprised of two women) - is illegitimate (which I assume means "not worthy of recognition"). And that right there is the problem.
Under federal and Massachusetts state law, a civil marriage is the union of two persons, regardless of sex or gender. A civil marriage of two women is the same as the civil marriage of two men and is also the same as the civil marriage of a man and a woman. In the eyes of the law, all are legitimate. It's a fairly simple and straightforward concept and has been written about extensively.
So, would a purported civil marriage of three women be any less legitimate than the civil marriage of two women? Yes. The law would not recognize the former and the law does and will continue to recognize the latter.
I think a more pertinent question is why the National Review uses terms like "lesbian twosome" when the more accurate and less salacious phrase "married couple" exists.