The United States Supreme Court ruled on June 26, 2015 that same-sex married couples are entitled to the same equal protection under the law, and their marriage must be recognized by every state.
The case, Obergefell v. Hodges, was actually a consolidation of several cases dealing with same-sex marriage rights under the 14th Amendment, which extends the 5th Amendment equal protection clause to the sattes. Same-sex couples already received equal treatment under federal law after U.S. v Windsor , i.e. for federal tax purposes and other benefits under federal law such as ERISA. Jim Obergefell was married in Maryland but at the time his husband died they were Ohio residents. Ohio, however, refused to recognize Obergefell as a surviving spouse. He sued the state of Ohio, naming Hodges, its director of the Department of Health.
What was established by the Supreme Court ruling in Obergefell is that states are required to issue marriage licenses to individuals of the same gender and to recognize same-sex marriages of residents who were married in another state where the marriage was legally valid.
Between the Obergefell and Windsor cases it appears that going forward in the United States that same-sex marriage will retain the status of opposite sex marriages, will enjoy the same state and other spousal benefits of marriage, divorce, adoption, death benefits, and inheritance through intestacy.
What this means in the estate planning arena is that if you fail to make a plan that Uncle Sam will have one for you. Thus, although same-sex married couples are afforded spousal rights under the laws of intestacy, it is still as relevant as ever to proactively make an estate plan. All of the valid reasons for planning apply across the board. It is still best practice to take control of your own estate planning, and to leave as little to state law interpretation as possible.