Massachusetts highest court ruled on February 4, 2004, that anything less than same sex marriages is unconstitutional. The court's decision will stand until 2006, when a constitutional amendment defining marriage as a union between one man and one woman can placed on the ballot. In response, the lawmakers in Massachusetts are preparing to vote on a proposed amendment to the state's constitution that would seek to make the court's ruling moot, by defining marriage as a union between one man and one woman, thus expressly making same sex marriages illegal in Massachusetts.

In a similar decision issued in Vermont in 1999, Vermont's highest court told the Vermont lawmakers that it could allow gay couples to marry or it could create a separate category with the same rights and benefits of marriage. The Vermont lawmakers chose to create a separate category called "civil unions".

The Massachusetts decision made no mention of the Vermont law on civil unions, pointing instead to a recent Ontario, Canada decision which changed the definition of marriage to include gay couples. The Massachusetts high court stated that any category short of marriage would establish an "unconstitutional, inferior and discriminatory status for same sex couples." "The history of our nation has demonstrated that separate is seldom, if ever equal."