The Impact of Twitter Adoption on Lawmakers’ Voting Orientations

Social media has been found to be influential in a variety of contexts. From mobilizing the crowd in social movements to helping refugees settle into a new country, social media has had a significant impact. This study examines the role of social media in Congressional representation in a democratic political system. We intend to assess the impact of U.S. Representatives’ Twitter adoption on their voting orientations in the U.S. Congress. In particular, we consider whether the adoption of Twitter by representatives makes them vote more in line with the political ideology of their constituents. We constructed a panel data for 445 members of the 111th U.S. House of Representatives across a period of 24 months. We exploited the variation in joining Twitter across representatives to identify the impact of joining and using Twitter on voting orientations. Using fixed effects and difference-in-differences approaches, along with propensity score matching to address potential endogeneity in representatives’ Twitter adoption decisions, we found that representatives’ adoption of Twitter causes them to vote more in line with their constituents. Furthermore, the effect of Twitter adoption is more salient when a representative’s party differs from the party affiliation of the constituent or when Twitter use per capita is higher in the representative’s state. To identify the underlying mechanism of influence, we conducted further analysis on one of the important issues in the 111th Congress. Our results indicate that the volume of tweets directed at representatives signals the importance of certain bills to constituents. When representatives vote on bills that are the focus of a large volume of constituents’ tweets, they vote in a manner more aligned with their constituents’ opinions. Interestingly, the opinions the tweets express do not significantly influence their votes, suggesting that representatives are aware of the potential bias in opinions cascaded in tweets.

The online appendices are available at https://doi.org/10.1287/isre.2018.0791.