The Defense of Marriage Act (DOMA) is a U.S. federal law defining marriage as only a heterosexual union of a man and a woman. The law is intended to curtail the legalization of same-sex marriage under the Full Faith and Credit clause of the United States Constitution by allowing a state to determine for itself whether it must recognize such a union recognized by other states or jurisdictions.

It was signed into law by President Bill Clinton on September 21, 1996 after moving through a legislative fast track and overwhelming approval in both houses of the Republican controlled United States Congress.

Critics of DOMA argue that the law is unconstitutional on several grounds including:

  • Congress over-reached its authority under the Full Faith and Credit clause
  • the law illegally discriminates and violates the equal protection clause
  • the law violates the fundamental right to marriage (including same-sex marriage) under the due process clause

Several challenges to the law's constitutionality have been presented to the United States Supreme Court since its enactment, but so far the Court has declined to review any such cases. Many states have still not decided whether to recognize same-sex marriages or not. Some states have by legislation or referendum overturned their state court's recognition of such unions while Vermont is currently the only state to have given some legal recognition to such. California as well has a state-wide system for the registration and recognition of domestic partnerships.

In response to the growing number of legal and political challenges, some proponents of DOMA have proposed the Federal Marriage Amendment to the United States Constitution, which would override certain local and state loopholes and remove any possible application of the Constitutional "full faith and credit clause" being applied to same-sex partnerships, marriages or civil unions in other states.

"The bill amends the U.S. Code to make explicit what has been understood under federal law for over 200 years; that a marriage is the legal union of a man and a woman as husband and wife, and a spouse is a husband or wife of the opposite sex." [1]

See also: Same-sex marriage in the United States.

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