United States Polygamy is the act or condition of a person marrying another person while still being lawfully married to another spouse. It is illegal in the United States. The crime is punishable by a fine, imprisonment, or both, according to the law of the individual state and the circumstances of the offense.

How common is polygamy in the US?

One-in-five U.S. adults believe that polygamy is morally acceptable, a recent Gallup poll found. This share has almost tripled (from 7%) since the question was first asked in 2003, but is still among the least accepted behaviors Gallup asks about.

Can polygamy be successful?

Monogamy Is No More Successful Than Polygamy, And Research That Shows Otherwise May Be Biased, Study Says. Years of scientific research have shown that monogamy, or the idea of one man mating with one women for their entire lives, is better than polygamy.