Marina Adshade is an economist at Dalhousie University. She writes regularly on the economics of sex and love on her blog Dollars and Sex
The overwhelming majority of Canadians do not want to live in a polygamous household and, from an economic perspective, that observation is a bit of a mystery.
For a country like Canada, in which wealth is very unequally distributed, economic theory predicts that wealthy men should have more of everything, including wives. This doesn't suggest that wives are property. It suggests that if income matters then women who are maximizing their welfare, and the welfare of their children, should prefer to be the second, third, fourth wife of a very wealthy man to being the only wife of a poor man. Yet, despite high levels of inequality, the industrialized nations of the world all have adopted monogamy as the dominant marriage institution.
The explanation for why monogamy is preferred has to do with the way in which personal wealth is generated in industrialized nations.
In industrialized nations wealth is generated by those who are highly skilled. There is an economic argument for having only one spouse in an economy where wealth is a function of education - better educated men want to have better educated children and the best way to do that is for those children to have a well educated mother. Educated women have more bargaining power in the household and are better equipped to negotiate an arrangement where they are the only wife. Less educated women marry less educated men, but those men can only afford one wife anyway, and so monogamy pervades.
In Canada we don't have monogamy because the laws enforce this marital arrangement, we have these laws because historically this has been the arrangement that the majority has preferred.
So the question is, if monogamy is the best arrangement for those who can afford additional spouses, why does this institution need to be enshrined in the law? In the economic sense a policy is not optimal if someone can be made better off without making others worse off. If this is the criterion, then it has to be that criminalization of polygamy not be an optimal policy. If we allow everyone to act in their own best interests when making marriage choices, and assume that parents act in the best interest of their children, then surely those who chose to live in a polygamous household are better off than they would be in a monogamous household. They have to be because that is the arrangement they have chosen.
You can't make someone better off by forcing them to choose an alternative form of marriage that they do not prefer.
You may be worried that someone is being made worse off - the poor guys who can't find a wife because some men are taking more than their share. But, there will never be so much polygamy in Canada that it will add to the pool of men who will never marry.
Anyhow, the fact that so many women prefer to remain single than to be married to man who they don't desire as a husband is a much bigger contributor to bachelorhood than polygamy ever will be.
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