The legalization of same-sex marriage in a state is a signal that causes certain groups to change their opinion to support the policy

Five years ago, Iowa became the third U.S. state to allow same-sex marriages when the state Supreme Court issued a unanimous and very unpopular decision in the case Varnum v. Brien. Since this decision, public attitudes towards same-sex marriage in the state, and the United States in general, have changed dramatically. Rebecca Kreitzer, Allison Hamilton and Caroline Tolbert draw on a unique panel telephone survey in which the same individuals are interviewed before and after the Iowa Supreme Court legalized same-sex marriage to understand what groups of citizens were most likely to change their opinions on marriage rights in response to the Court’s decision. We find that the signaling of new social norms by the Court pressured some respondents to modify their attitudes. As the states continue on this rapid trajectory of legalizing same-sex marriage, we may see substantial shifts in attitudes towards LGBT rights.