Perspective
Now that same-sex marriage has been given the thumbs-up by SCOTUS, I've heard people suggest that polygamy is likely to follow suit after an appropriate interval. I don't know, though. See, same-sex marriage was much more of a religious issue than a practical problem. Heck, I think there were cases back before the modern age where same-sex marriage did happen because one of the parties dressed as an opposite-sex individual and the pair procured a marriage license form a clueless official. We've already got all the infrastructure to support cohabitating pairs; the only question was how much we could regulate who those pairs could be.
Polygamy is going to be a different kettle of fish, though. Just as an example from my own work - I do taxes. You can file Single, or Married Filing Joint, or Married Filing Separately. The latter two assume a single spouse. And more to the point, all the tax tables assume either one or two people. If you have a group of four people who are married in a poly group, and those folks all work, they're going to end up in a much higher tax bracket than two couples would. So to be fair, you really ought to revamp all the tax tables, not to mention all of the IRS forms. That's what I mean about infrastructure. Not saying it's a good thing or a bad thing - just that there are practical issues that didn't exist for the same-sex marriage debate.
Polygamy is going to be a different kettle of fish, though. Just as an example from my own work - I do taxes. You can file Single, or Married Filing Joint, or Married Filing Separately. The latter two assume a single spouse. And more to the point, all the tax tables assume either one or two people. If you have a group of four people who are married in a poly group, and those folks all work, they're going to end up in a much higher tax bracket than two couples would. So to be fair, you really ought to revamp all the tax tables, not to mention all of the IRS forms. That's what I mean about infrastructure. Not saying it's a good thing or a bad thing - just that there are practical issues that didn't exist for the same-sex marriage debate.