We examine whether and how roll call voting depends on legislators’ beliefs about peers’ vote intentions. Through field experiments conducted in three state legislatures, we find that information about peers’ support for bills influences respondents’ beliefs about bill passage, but not their stated or revealed support for legislation. We then analyze a legislative procedure — the use of sequential roll call voting — and its replacement by electronic voting to study how asymmetries in information about peers’ votes affected roll call voting in the US Congress and Nevada legislature. We find that earlier voters were more likely to abstain under sequential voting procedures, but not under the electronic procedures that replaced them. Effects appear larger on lopsided, less salient votes, and on days on which more roll calls were held. We conclude that peers’ votes more likely affect whether legislators cast a vote than how they vote, and that a key role of peers’ votes is to reinforce legislators’ predispositions rather than persuade them to switch positions.

Persuasion and Ideological Voting in Legislatures (with Daniel Bergan)

American legislators are generally thought to be ideologues who take consistently partisan positions, but recent research suggests they are also pliant targets of persuasion campaigns by special interests, lobbyists, fellow legislators, and even academics. This paper explores this seeming discrepancy. First, we revisit the credibility of findings of legislative persuasion to determine whether legislators’ positions can be changed, and if so whether such changes are robust and long-lasting. Second, we examine whether persuasion works against, or alongside, ideology. Finally, we interview legislators to hear their experiences as targets of persuasion. We conclude that legislative persuasion can be long-lasting and found on bills other than those targeted by advocates. Persuasion can increase ideological position-taking and polarization by allowing legislators to take positions consistent with their broader ideology. Finally, legislative persuasion most resembles a process of policy-specific learning rather than deep ideological conversion or shallow priming or pandering. Our findings suggest legislative persuasion may play a key role in how parties, interest groups, and constituents drive polarization and highlight how legislative processes influence roll-call based measures of legislator ideology.

The Minimal Effects of Public Health Campaigns on Travel During the COVID-19 Pandemic (with Ethan Bueno de Mesquita, Mehdi Shadmehr, and Benjamin Shaver)

We explore the effectiveness of a public health campaign via a large-scale field experiment during the COVID-19 pandemic. In 2020, approximately 125,000 households were sent mail from health experts encouraging social distancing. Targeted geographies received varying dosages of treatments, and some targeted households were informed that neighbors also received the messages, to highlight the strategic considerations underlying social distancing. We find minimal effects of the campaign on holiday travel and on other social distancing behavior. We consider our results in light of a similar intervention and conclude that travel was unlikely to be influenced by messages from public health experts.