<P> The community property concept originated in civil law jurisdictions but is now also found in some common law jurisdictions . The states of the United States that recognize community property are primarily in the Western United States; it was inherited from Mexico's ganancial community system, which itself was inherited from Spanish law (a Roman - derived civil law system) and ultimately from the Visigothic Code . While under Spanish rule, Louisiana adopted the ganancial community system of acquests and gains, which replaced the traditional French community of movables and acquests in its civil law system . </P> <P> The community property system is usually justified by the pragmatic recognition that such joint ownership recognizes the theoretically equal contributions of both spouses to the creation and operation of the family unit, a basic component of civil society . The countervailing majority view in most U.S. states, as well as federal law, which is based on traditional American family values and gender roles, is that marriage is a sacred compact in which a man assumes a "deeply rooted" moral obligation to support his wife and child, whereas community property essentially reduces marriage to an "amoral business relationship". </P> <P> In the United States there are nine community property states: Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, and Wisconsin . Alaska has also adopted a community property system, but it is optional . Spouses may create community property by entering into a community property agreement or by creating a community property trust . In 2010, Tennessee adopted a law similar to Alaska's and allows residents and non-residents to opt into community property through a community property trust . The commonwealth of Puerto Rico allows property to be owned as community property also as do several Native American jurisdictions . In the case of Puerto Rico, the island had been under community property law since its settlement by Spain in 1493 . The U.S. Supreme Court ruled that a similar statute allowing spouses to elect a community property system under Oklahoma law would not be recognized for federal income tax reporting purposes . The Harmon decision should also apply to the Alaska system for income reporting purposes . </P> <P> If property is held as community property, each spouse technically owns an undivided one - half interest in the property . This type of ownership applies to most property acquired by each spouse during the course of the marriage . It generally does not apply to property acquired prior to the marriage or to property acquired by gift or inheritance during the marriage . After a divorce, community property is divided equally in some states and according to the discretion of the court in the other states . </P>

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