【海外の反応】一夫多妻はなぜ違法？「税金より厄介な本当の理由」に海外ネット民が納得

it’s not really just “tax reasons” or some moral rule, it’s more about how marriage is structured in law. Marriage isn’t only symbolic, it’s a legal contract between two people that ties into things like inheritance, taxes, medical decisions, property rights and divorce rules. All of that is built on a simple 1-to-1 system, so when you try to extend it to multiple spouses it starts breaking down pretty quickly. You run into questions like how inheritance is split between several spouses and children, how divorce would even work if only one person leaves the group, how tax benefits or survivor benefits are divided, and what happens when multiple spouses have equal medical authority but disagree on decisions. Even property and debt become messy because responsibility and ownership aren’t designed to be shared between more than two people in a single legal unit. In theory you could redesign the system to handle it, but it would basically mean rewriting a huge part of family, tax and inheritance law, not just tweaking marriage rules. So it’s less about a moral ban and more about the fact that the whole legal framework is built around couples, and plural marriage doesn’t really fit without major structural changes.

It creates a lot more mess with everything – if there's children and a split, is child support evenly divided between everyone, even if some people didn't want kids and are completely uninvolved? Should ot be weighted by length of time in the relationship or flat rate? Inheritance is similar – if it's just one person, then stuff generally goes to them, barring an explicit instruction to the contrary (ie a will). If there's 4 other people, how does that work as a default? If there's a divorce, does that break the whole thing apart, or can it be split into multiple still-married blocks, and how does that work for finances and property? Basically take all the messy stuff that's evolved over generations for marriages, and start relitigating that again to try and establish a multi-person baseline – not simple or easy! Kids are generally presumed to be children of the married pair – if it's actually 3+ people, to what degree can the others claim parental rights? And to what degree can the children invoke parental rights from people not actually their parent? It's possible to develop rules and baselines for it, but it's a lot of hassle, for something that doesn't really have a massive of support behind it, so it's not really urgent for lawmakers to push for

Something which I'm not sure has been mentioned yet is that you end up with a lot of spare men, because It's always one man with multiple wives and never one woman with multiple husbands. 

What happens to the leftover men? It's quite easy to then get yourself into a situation where the country has a lot of young men who are frustrated (sexually frustrated, frustrated that their life isn't turning out the way they wanted, frustrated with the low social status that is often associated with being unmarried). 

Lots of young, frustrated and often angry men with time on their hands and little to lose is a good way to end up with social unrest, unpleasant political movements and so on – unless you suppress it in other ways. 

Utah has a problem with the "lost boys" who are essentially kicked out of the FLDS and left to fend for themselves once they come of age. I watched quite a good documentary on them a few years ago called the Sons of Perdition; it's awful what the cult does to them. 

It's the same reason why we ban sex selection in reproductive healthcare. 

Probably because polygamy in practice almost always means polygyny and the exploitation of girls.

Probably because polygamy in practice almost always means polygyny and the exploitation of girls.