Gender Diversity and Same-Sex Marriage

Abstract

Opponents of same-sex marriage have recently adopted a curious new argument. The argument goes something like this. The Supreme Court has held that diversity is a compelling state interest in institutions of higher education. Opposite-sex marriage includes gender diversity, while same-sex marriage does not. Therefore, states may allow same-sex marriage while banning opposite-sex marriage — even if the ban triggers heightened scrutiny under equal protection or due process — because opposite-sex marriage furthers gender diversity, while same-sex marriage does not.The gender diversity argument against same-sex marriage has made its way into a number of briefs during the recent increase in challenges to same-sex marriage bans. For example, it appeared in multiple amicus briefs in United States v. Windsor, as well as in various filings in challenges to Utah's same-sex marriage ban in the Tenth Circuit and Kentucky's same-sex marriage ban in the Sixth Circuit.Despite this newfound popularity, the gender diversity argument fails for a number of reasons. It erroneously conflates sex and gender, impermissibly relies on sex and gender stereotyping, lacks credible empirical support, draws untenable analogies, runs afoul of well-established doctrine, and, taken to its logical conclusion, leads to a inexorably to a number of consequences that are either universally undesirable or that we are fairly certain its proponents do not support. In short, we think the argument wholly unsuccessful, and urge courts not to entertain it.