Last month, the Supreme Court declared unconstitutional the Defense of Marriage Act's requirement that only opposite-sex marriages may be recognized for federal law purposes. The Court's decision became effective July 21, 2013. As a result, the federal government must now recognize same-sex couples that are in "lawful marriages." The ruling did not affect the portion of the Defense of Marriage Act that allows states to define marriage as opposite-sex marriage and to refuse to recognize same-sex marriages entered into in other states.

The ruling's implications for benefit plans are broad, but uncertain. In using the term "lawful marriages," the Supreme Court did not address whether the federal government is required to recognize marriages validly entered into in states that recognize same-sex marriage by same-sex spouses who reside in states that do not recognize same-sex marriage or to treat civil unions or registered domestic partnerships as "lawful marriages" for federal purposes. The Court also did not address whether the ruling applies retroactively.

The ruling's effects on benefit plans will depend in large part on how the Internal Revenue Service and Department of Labor interpret the ruling. We do not recommend amending plans prior to the issuance of guidance. However, employers should review benefit plan documents as soon as possible to determine how their plans may be affected by the ruling. In particular, employers should review the definitions of "spouse" and "dependent" and other provisions affected by participants' marital status, including provisions that determine beneficiaries. Administrative changes are most likely to be necessary under plans that define "spouse" by reference to federal law or the law of a state that recognizes same-sex marriage.