system
Given the following post, respond as if you're commenting on Reddit:
human
CMV: There's no good argument for gay marriage that doesn't also include polyamourous marriage.

From the opening remarks at the Supreme Court today:


   *Mr. Chief Justice, and may it please the Court: The intimate and committed relationships of same­sex couples, just like those of heterosexual couples, provide mutual support and are the foundation of family life in our society. If a legal commitment, responsibility and protection that is marriage is off limits to gay people as a class, the stain of unworthiness that follows on individuals and families contravenes the basic constitutional commitment to equal dignity.*

Are we willing to declare that polyamourous relationships cannot be intimate or committed? Do they not provide mutual support? Are such people supposed to not feel like second-class citizens if there love is not OK but everyone else's is? Do we not worry about their feeling a similar 'stain of unworthiness'?

Some arguments I've heard from another thread are: "Well, that would really complicate the tax code." I kinda think that's the tax code's fault. We don't need to have a tax code that treats people different according to their marital status.

"This would make pre-nups and inheritance more complicated." Again, this seems like a side thing, not an argument for denying people rights, if such rights exist. 

"One fails rational basis review, and the other doesn't." I'm not a lawyer, but I do find this the technically best argument, but it still seems thin to me. You can easily say the Government has as compelling interest in keeping marriage between man and woman as you can say it has interest in keeping it between only 2 people. Fundamentally, man + woman = child, which is on of the main things about marriage. If anything, polyamorous relationships that contain at least one man and one woman pass that test easier than homosexual relationships do.

Does anyone have anything else? Or can you expand one of the previous arguments to something more convincing?
gpt
Marriage is a unique form of contract law that allows people to share finances, property ownership, tax burden, insurance benefits, and more.

Allowing an unlimited number of people to join into such an arrangement would be a recipe for abuse.  For example:

1. An entire corporation of 150 people avoid almost all labor and tax laws by becoming a marriage union.  The corporation may even coerce employees to join.

2. A single soldier or retiree supports 200 woman from his hometown with spousal benefits.

3. A criminal organization makes all their communications protected by spousal privilege.