Congress Members Are More Likely to Follow Issue Priorities, Not Lead Them

In the APSA Public Scholarship Program, graduate students in political science produce summaries of new research in the American Political Science Review. This piece, written by Maryann Kwakwa, covers the new article by Pablo Barberá, University of Southern California, Jonathan Nagler, Patrick J. Egan, Richard Bonneau, John T. Jost  and Joshua A. Tucker, New York University, Who Leads? Who Follows? Measuring Issue Attention and Agenda Setting by Legislators and the Mass Public Using Social Media Data”

Who do legislators respond to? Do lawmakers follow the issue priorities of the public or is it the other way around? To whom should we expect members of Congress to be responsive: the general public, attentive voters, or their staunchest supporters? These are the questions that Barberá et al. answer in their recent article, “Who Leads? Who Follows? Measuring Issue Attention and Agenda Setting by Legislators and the Mass Public Using Social Media Data.”

Using Twitter to measure the political agendas of legislators and the American public, Barberá et al. find that lawmakers bring awareness to issues that U.S. citizens prioritize more often than they highlight their own policy goals. They also find that members of Congress are more responsive to party supporters than to the general public. Ideally, we might expect lawmakers to devote time to issues that reflect the priorities of the general population. However, Barberá et al. show that there is little evidence to support this claim. Rather, members of Congress are more likely to change their behavior to accommodate the political priorities of their core party supporters.

Some scholars argue that legislators seeking to increase their chances of reelection should focus on issues that a majority of the general public deems relevant.

Barberá et al. analyze all of the tweets sent by members of Congress from January 2013 to December 2014 to explore whether legislators’ political agendas change after shifts in issue attention by three different subgroups of the American public: partisans, people who are highly attentive to politics, and a random sample of U.S. Twitter users.

Some scholars argue that legislators seeking to increase their chances of reelection should focus on issues that a majority of the general public deems relevant. However, others believe that members of Congress have an incentive to be mostly responsive to attentive voters, not median voters. Because most voters do not follow day-to-day politics and many do not have clear issue priorities, the authors hypothesize that changes in attention by citizens who frequently follow politics may predict changes in attention by members of Congress.

There is also strong evidence to suggest that legislators are primarily interested in responding to core party supporters. Not only do these constituents have political interests that are easier to identify and represent, but they also play an active role in nomination processes. Although many scholars find that legislators are more likely to represent the policy preferences of their supporters rather than those of the mean voter, Barberá et al. demonstrate that this is the case particularly when it comes to the types of issues that members of Congress pay attention to.

Are members of Congress following their constituents and, if so, are they following particular types of constituents?

The answer to both of these questions is yes. The authors find that changes in issue attention by citizens are highly related to the issues that members of Congress discuss. Although politicians from both the Democratic and Republican Parties are able to persuade party supporters and attentive citizens to acknowledge some of their issue priorities, ultimately, the ability of the public to lead the agenda of Congress members is much greater than the ability of Congress members to lead the agenda of the public.

The authors also find that the media plays a powerful role in agenda setting. Learn more about how mass media coverage favors the issue priorities of the American public by reading the rest of this article here.

Overall, Barberá et al. show that politicians pay attention to the issue priorities of their party supporters rather than to those of attentive voters and the general public. Their conclusions about lawmaker responsiveness help clarify how partisanship shapes political agendas at present.


  • Maryann Kwakwa is a Ph.D. candidate (A.B.D.) in American Politics and Constitutional Studies at the University of Notre Dame. Her research interests include civic engagement, education, race/ethnic politics, and democratic citizenship. In her dissertation, Maryann uses a mixed-methods approach to analyze the effect of undergraduate college experiences on civic engagement in the United States. Maryann graduated from Oberlin College in 2014 with a Bachelor of Arts in Law and Society and a minor in Politics. At Notre Dame, Maryann has served on numerous departmental committees, led discussion sections for introductory American Politics courses, and taught a senior seminar, “Politics in Cyberspace,” as the instructor of record. She has also published a virtual review article for the American Political Science Association and two, co-authored journal articles, which appear in Politics, Groups, and Identities.
  • Article details: American Political Science ReviewFirst View, Who Leads? Who Follows? Measuring Issue Attention and Agenda Setting by Legislators and the Mass Public Using Social Media DataPublished online: 12 July 2019
  • About the APSA Public Scholarship Program.