This week the Supreme Court heard arguments on two cases looking at the constitutionality of same-sex marriage. Specifically, the cases were about measures that ban recognition of gay marriage by the federal government and the state of California. At the federal level, the Court heard about the Defense of Marriage Act (DOMA), which bans the recognition of a same-sex marriage and entails over 1,100 different laws that consider marriage status when determining an individual’s rights and responsibilities. And some of those laws determine how much that individual owes in taxes.
The discriminatory effect of the DOMA, which was signed into law in 1996, in tax law is at the center of United States v. Windsor. The original petitioner in the case, Edith Windsor, was forced to pay $363,000 more in federal estate taxes because under DOMA, her same-sex marriage is not recognized for tax purposes and thus is not eligible for the “surviving spouse” estate tax exemption available to heterosexual spouses. If the Supreme Court rules in favor of Windsor and declares DOMA unconstitutional, it would mean that same-sex marriages will be recognized by the federal government for all purposes, including taxes.
While such a ruling would have a relatively small impact in terms of the estate tax since almost no one pays it, there are many other federal tax provisions that do affect most married couples. The New York Times, for example, points to the fact that DOMA prevents same-sex spousal health benefits from being treated as a tax-exempt benefit, therefore increasing the tax bill of individual same-sex couples by a few thousand dollars each year.
Perhaps the most widespread tax impact would be on same-sex spouses who are not currently allowed to file their federal tax returns jointly. According to an analysis by CNN and tax experts, some same-sex spouses may currently be paying as much as $6,000 in extra taxes each year because of DOMA. While many same-sex spouses could receive a substantial tax benefit from filing jointly, they could also end up paying more in taxes due to the infamous marriage penalty, depending on each spouse’s level of income.
There is also a larger fiscal effect to consider. A 2004 Congressional Budget Office (CBO) report (PDF) estimated that federal recognition of same-sex marriage would actually reduce the deficit by roughly $450 million each year, through a combination of higher revenues and lower outlays. In other words, ruling DOMA unconstitutional would not only end same-sex marriage discrimination in the tax code and other parts of federal law, but would also have the bonus effect of slightly reducing the deficit.