Just what can someone consent to is a whole other thread, and a interesting discussion if you want to post it over in the Discussion Club. But I have just the other night had this discussion with a group of very smart, very well educated people and it comes down to the fact that as long as we hold that everyone is of sound mind and body and not being coerced, then it is hard to justify taking away someone's right to consent even to extreme things like incest and cannibalism.
I don't really have an issue with the idea of Poly marriages, but the entire marriage legal framework would have to massively change, because right now marriage is clearly a contract between two people.
One of the things that would have to happen is that marriage would have to be redefined as a legal shell entity like corporations are. People could then join and leave marriages based on the rules of the marriage. It would make a lot of things like divorce a lot simpler because it will force people to work out those sorts of things in advance.
Also all you commitment phobic men, I have news for you. Basically no normal woman is going to agree to be in a poly marriage with 1 guy and multiple wives. What would actually happen is 1 women with multiple men, because lets face it tits attract way more men than dick attracts women. So if poly marriages actually happen, you will probably end up with even less sex than you currently have.
As someone who has actually been in polyamorous relationships I can say with authority that you are wrong. Women tend to form strong familiar bonds with each other, and are much better at sharing a man then men are at sharing a women. This also hold off the Coolidge effect and leads to a very active sex life.
There is also nothing from stopping people from have open marriages/swinging now or even having a live in second "wife." There is just no legal framework, currently for allowing more than 2 people to enter into a marriage contract.
That is kind of correct. There are some laws that poly people can fall foul of. But, more importantly that is not what we are talking about, we are talking about getting married, not being lovers.
Which this is why poly and same-sex marriages are not actually all that related. SSM would use the same legal framework that exists today, they just want access to it. Poly would require a whole new legal framework that no one currently has access to, so everyone is seen equal under the law.
Of course, you are right. We would not want to make our legislator work hard at making laws or anything. They might might have to miss on one of their lobbyists dinners.
But having said that, while they use similar arguments, SSM and Poly Marriage are separate issues that need to each have their own day.