Bigamy is the practice of being married to two people at once. This form of polygamy is considered illegal in many Western countries, and it has historically been a topic of contention, especially in the United States. Some Mormon sects support the practice of polygamy, and resent state interference in what they view as their private affairs. As a general rule, this crime is rarely prosecuted, and when it is, the penalty varies; the primary spouse may be ordered to serve time in jail, and potentially to pay a fine, for example.
In a classic example of bigamy, a man marries a woman, and then marries another several years later, while he is still legally married to the first women. Depending on the culture in which this occurs, the second marriage may be undertaken with the full consent of both wives, or the second marriage may be concealed. Should the man take a third wife, he would be committing trigamy; if he added additional spouses to the mix, it would become polygamy, or, more accurately, polygyny.
Sometimes, people commit this act by accident, and there is some leeway in the law to provide for this. For example, if a couple separates but does not formally divorce and one spouse remarries, this could be considered a form of bigamy, but it is often permitted if the separation was more than five years ago, and the remarrying partner made a good faith effort to formally divorce the other. In some regions, if someone has been missing for five or more years, he or she could be legally declared dead, allowing the surviving spouse to remarry without fear of charges.
In the United States, where polygamy has been a particularly fraught issue, several court cases and laws have clearly dictated that being married to more than one person at the same time is illegal. The Morrill Anti-Bigamy Act of 1862 specifically outlawed the practice, and it was upheld in a Supreme Court challenge in 1878. The laws are often difficult to enforce, however, especially since they targeted the Mormon community, which lived in isolated regions of the American West. Even today, pressing charges can be challenging, and such charges are usually integrated into a larger indictment.
In some regions of the world, being married to two people is perfectly acceptable and commonplace, due to cultural or religious values. Some people feel that such marriages can be beneficial for those involved, allowing the partners to share the work in the marriage and work together as a team. Others feel that it exploits one or more of the people involved in the marriage, especially when a second wife is treated more like a household slave than a member of the family.