According to the United States Government Accountability Office (GAO), there are 1,138 statutory provisions[1] in which marital status is a factor in determining benefits, rights, and privileges.
The conflict between this definition and the Due Process Clause of the Fifth Amendment to the Constitution led the U.S. Supreme Court to rule DOMA unconstitutional on June 26, 2013, in the case of United States v. Windsor.
An update was published in 2004 by the GAO covering the period between September 21, 1996 (when DOMA was signed into law), and December 31, 2003.
There are some laws that either benefit or penalize married couples over single people, depending upon their own circumstances: In addition, community-property states frequently have forms of ownership that allow a full basis step-up on one's own share of community property on the death of a spouse (in addition to the normal step-up on spouse's assets).
Following the 2004 GAO report at least one bill, the Uniting American Families Act, has been proposed to attempt to remedy some of the differences in rights between same-sex partnerships and marriages.