Religious Diversity and Party Control in the States: Explaining Adoptions of Same-Sex Marriage Laws

Despite the burgeoning literature on morality policies in the US, the conditions under which legislation in favor of same-sex marriage has been adopted remain largely unexplored. This study examines the enactment of marriage equality laws in the US states from 2004 to 2014, by focusing on the interplay between religious diversity and party control of the state government. I argue that incorporating the religious composition of each state allows to better understand the crucial role that political parties play in the policy-making process. The results of the discrete-time event history analysis show that party control of the state government is an important factor determining policy output only in those states that are religiously more diverse. Conversely, in religiously homogeneous states, the effect of Democratic versus Republican and divided governments is not significant.