The Defense of Marriage Act (DOMA) is a United States federal law passed by the 104th United States Congress and signed into law by President Bill Clinton. It defines marriage for federal purposes as the union of one man and one woman, and allows states to refuse to recognize same-sex marriages granted under the laws of other states. The act's provisions were ruled unconstitutional or left effectively unenforceable by Supreme Court decisions in the cases of "United States v. Windsor" (2013) and "Obergefell v. Hodges" (2015).