Is polygamy bad for society?

As the U.S. reacts to Warren Jeffs' shocking legal victory, Canada is embroiled in its own battle over polygamy. The British Columbia Supreme Court is considering whether outlawing polygamy would violate the constitutional right to religious freedom and freedom of expression. The case was prompted by the arrest of two of the country's own Jeffs-like characters -- the leaders of Bountiful, a rather, um, bountiful Mormon group in B.C. -- but it gets at a much larger question: Is polygamy bad for society?