On June 26, 2013, the U.S. Supreme Court, by a 5-4 decision, overturned section 3 of the federal Defense of Marriage Act (DOMA) which effectively denied federal recognition of same-sex marriages which are legal at the state level. United States v. Windsor.
In 2013, Colorado enacted the Colorado Civil Union Act, which provides couples, including gay & lesbian couples, with the right to enter into a civil union, and to enjoy the rights, privileges, and headaches that married couples enjoy. For the full details, see Colorado Civil Unions in the Colorado Divorce & Family Law Guide.
In August 2012, the Colorado Court of Appeals issued a decision which affects annulments in Colorado in two important ways: (1) it approved marrying for a green card as a basis to find a fraudulent marriage, and (2) it held that a spouse who fraudulently induced the other to marry is not entitled to maintenance or a share of the marital estate beyond that spouse's own financial contributions. In re: the Marriage of Joel, 2012 COA 128.