No state legally allows polygamy. However, Utah and Colorado largely ignore polygamy as long as the parties remain discreet. There is no federal law prohibiting polygamy.
Latter Day Saint movement
Legal status of polygamy
The Latter Day Saint movement (also called the LDS movement or LDS restorationist movement) is the collection of independent church groups that trace their origins to a Christian primitivist movement founded by Joseph Smith in the late 1820s. Collectively, these churches have over 15 million members. The vast majority of members belong to The Church of Jesus Christ of Latter-day Saints (LDS Church), with their predominant theology being Mormonism. The LDS Church self-identifies as Christian. A minority of Latter Day Saint adherents, such as members of the Community of Christ, believe in traditional Protestant theology, and have distanced themselves from some of the distinctive doctrines of Mormonism. Other breakaway groups include the Remnant Church of Jesus Christ of Latter Day Saints which support lineal succession of leadership from Joseph Smith's descendants, and the more controversial Fundamentalist Church of Jesus Christ of Latter-Day Saints, who defend the practice of polygamy.
The movement began in western New York during the Second Great Awakening when Smith said that he received visions revealing a new sacred text, the Book of Mormon, which he published in 1830 as a complement to the Bible. Based on the teachings of this book and other revelations, Smith founded a Christian primitivist church, called the Church of Christ. The Book of Mormon brought hundreds of early followers, who later became known as "Mormons", "Latter Day Saints", or just "Saints." In 1831 Smith moved the church headquarters to Kirtland, Ohio, and in 1834 changed its name to the "Church of Jesus Christ of Latter Day Saints."
Polygamy in North America
The legal status of polygamy (also known as bigamy where forbidden) varies from country to country. Many of the countries where the practice yet exists are underdeveloped, and their populations mostly illiterate, as well as having cultures oppressive of women. The only form in which polygamy is permitted in all places where it is permitted is that of polygyny, a man taking multiple wives.
A majority of the world's countries and nearly all of the world's developed nations, do not permit polygamy, and there have been growing calls for the abolition of polygyny in many developing countries. In the countries which do not permit polygamy, a person who marries a person while still being lawfully married to another commits bigamy. In all cases, the second marriage is considered legally null and void. Besides the second and subsequent marriages being void, the bigamist is also liable to other penalties, which also vary between jurisdictions.
Mormonism and polygamy
Polygamy is the practice of taking more than one spouse. Polygyny is the specific practice of one man taking several wives, is a common marriage pattern in some parts of the world. In North America polygamy has never been a culturally normative or legally recognized institution after it was colonized by Europeans.
Polygamy became a significant social and political issue in the United States in 1852, when The Church of Jesus Christ of Latter-day Saints (LDS Church) made it known that a form of the practice, called plural marriage, was part of its doctrine. Opposition to the practice by the United States government resulted in an intense legal conflict, and culminated in LDS Church president Wilford Woodruff announcing the church's official abandonment of the practice on September 25, 1890. However, breakaway Mormon fundamentalist groups living mostly in the western United States, Canada, and Mexico still practice plural marriage.
Polygamy (called plural marriage by Mormons in the 19th century or the Principle by modern fundamentalist practitioners of polygamy) was taught by leaders of The Church of Jesus Christ of Latter-day Saints (LDS Church) for more than half of the 19th century, and practiced publicly from 1852 to 1890 by a minority of families (between 20% and 30%).
The church's practice of polygamy has been highly controversial, both within Western society and the church itself. America was both fascinated and horrified by the practice of polygamy, with the Republican platform at one time referencing "the twin relics of barbarism - polygamy and slavery." The private practice of polygamy, or more specifically, polygyny, was instituted in the 1830s by founder Joseph Smith, Jr. The public practice of polygamy (“plural marriage”) by the church was announced and defended in 1852 by one of the Council of the Twelve Apostles, Elder Orson Pratt, by the request of the church President at that time, Brigham Young.
federal law prohibiting polygamy
A mating system is a way in which a group is structured in relation to sexual behaviour. The precise meaning depends upon the context. With respect to higher animals, the term describes which males mate with which females, under which circumstances; recognised animal mating systems include monogamy, polygamy (which includes polygyny, polyandry, and polygynandry) and promiscuity. In plants, the term refers to the degree and circumstances of outcrossing. In human sociobiology, the terms have been extended to encompass the formation of relationships such as marriage.
The primary mating systems in plants are outcrossing (cross-fertilisation), autogamy (self-fertilisation) and apomixis (asexual reproduction without fertilisation, but only when arising by modification of sexual function). Mixed mating systems, in which plants use two or even all three mating systems, are not uncommon.