The Supreme Court opinion on United States v. Windsor, No. 12-307 (2013) held that DOMA was unconstitutional under the Fifth Amendment when it failed to recognize same-sex marriage federally.
It is important to note that the reasoning behind this ruling was based on the fact that there are States which granted same-sex marriage but were not recognized federally. By failing to recognize those same-sex marriages, the government was discriminating against same-sex married couples. In doing so, same-sex married couples were deprived of the benefits and responsibilities of over 1,000 federal laws. Including protections under criminal law and provide financial harm to children of same-sex couples.
The Supreme Court noted that the State’s authority to regulate marriages was being squashed by the federal government. Based on precedent, “[e]ach state as a sovereign has a rightful and legitimate concern in the marital status of persons domiciled within its borders.” “The definition of marriage is the foundation of the State’s broader authority to regulate the subject of domestic relations with respect to the ‘[p]rotection of offspring, property interests, and the enforcement of marital responsibilities.'” (italics added).
Instead of respecting the State’s authority to regulate marriages, DOMA’s purpose was to “impose a disadvantage, a separate status, and so a sigma upon all who enter into same-sex marriages made lawful by the unquestioned authority of the States.”
Given that DOMA’s purpose was to impose restrictions and disabilities, the Supreme Court stated that “[b]y doing so [DOMA] violates basic due process and equal protection principles.”
The Supreme Court found that
DOMA’s principal effect is to identify a subset of state-sanctioned marriages and make them unequal. The principal purpose is to impose inequality, not for other reasons like governmental efficiency….
DOMA contrives to deprive some couples married under the laws of their State, but not other couples, of both rights and responsibilities. By creating two contradictory marriage regimes within the same State, DOMA forces same-sex couples to live as married for the purpose of state law but unmarried for the purpose of federal law, thus diminishing the stability and predictability of basic personal relations the State has found it proper to acknowledge and protect.