Katherine M. Franke, a professor of law and the director of the Center for Gender and Sexuality Law at Columbia Law School warns:

Here’s why I’m worried: Winning the right to marry is one thing; being forced to marry is quite another. How’s that? If the rollout of marriage equality in other states, like Massachusetts, is any guide, lesbian and gay people who have obtained health and other benefits for their domestic partners will be required by both public and private employers to marry their partners in order to keep those rights. In other words, “winning” the right to marry may mean “losing” the rights we have now as domestic partners, as we’ll be folded into the all-or-nothing world of marriage.

... Once the marriage ban in New York State is lifted, domestic-partner couples, both gay and straight, will risk losing access to health care and other benefits if their employers treat marriage as the only ticket for entitlement to these benefits, which are increasingly expensive.

... What’s difficult to explain is that for some lesbians and gay men, having our relationships sanctioned and regulated by the state is hardly something to celebrate. It was only a few years ago that we were criminals in the eyes of the law simply because of whom we loved. As strangers to marriage for so long, we’ve created loving and committed forms of family, care and attachment that far exceed, and often improve on, the narrow legal definition of marriage. Many of us are not ready to abandon those nonmarital ways of loving once we can legally marry.