The introduction chapter lays the groundwork for understanding the intricate relationship between Congress and information acquisition, particularly through committee hearings and witness testimonies. Highlighting the pivotal role of information in shaping legislative decisions, the chapter probes into the challenges faced by Congress in navigating the complex landscape of external expertise within a politically charged environment. The chapter delves into the critical questions driving the book’s exploration: How does Congress acquire information, and what factors influence the selection and content of information provided by external witnesses? It introduces the overarching themes of partisan incentives, institutional conditions, and the strategic nature of information acquisition, aiming to dissect their impact on legislative processes. By providing a comprehensive overview of the book’s scope, methodology, and key theoretical insights, the introduction sets the tone for a deep dive into the dynamics of congressional information-seeking behavior.

In this chapter, we examine how the politics of interbranch relations between the legislature and the bureaucracy affect the invitation of bureaucratic witnesses to hearings and how Congress can use hearings to control executive branch influence. We focus on the presence of divided government – when the party controlling Congress is not the party that controls the White House. We find that during periods of divided government, committees invited relatively fewer bureaucrats to testify; instead, they invited relatively more witnesses from think tanks, universities, and within Congress itself. This result is particularly pronounced when hearings were held on issues that the president prioritized. These findings are substantively important, especially given how the existing literature has characterized bureaucrats’ advantages in information and expertise in policy implementation vis-à-vis Congress. We provide evidence that under divided government, committees limited the amount of expert information from the executive branch that could be favorable to a president from the opposing party and instead welcomed outsiders to compensate for the relative loss of information from bureaucrats.

Chapter 7 scrutinizes how Congress’s internal resources impact the quantity and quality of information received by committees. Amid concerns over diminishing congressional capacity and the waning role of support agencies, the chapter explores the repercussions of downsizing initiatives – such as the elimination of the Office of Technology Assessment (OTA) – on committee information channels. Employing a difference-in-differences research design, the study reveals a stark decline in technical and scientific witnesses invited by committees heavily reliant on internally produced information post-OTA elimination. The findings underscore the critical role of robust congressional capacity in summoning research-based witnesses, emphasizing its pivotal significance in ensuring legislators’ access to vital scientific and technical insights.

This chapter explains the methodological approach behind the measurement of analytical information in witness testimonies. Focusing on House hearings from the 105th through 114th Congresses, the methodological approach quantifies technical information relevant to policymaking – analytical information – and shows how witness affiliations can capture meaningful differences in the amount of analytical information that witnesses provide Congress in committee hearings. Bureaucrats and research-affiliated witnesses excel in delivering analytical testimony, while citizens and religious institution representatives provide the least. The patterns in this chapter demonstrate that not all testimony provides the same type of information and that committees may receive different amounts of analytical information depending on the types of witnesses they invite. Taken together, the findings and patterns illustrated in this chapter motivate our argument that the composition of witnesses has important implications for committees, as witness invitations not only indicate from whom committees choose to hear but also signify the different types of information committees may ultimately receive.

This chapter introduces a novel dataset encompassing 731,810 witnesses across 74,077 House, Senate, and Joint standing committee hearings held between 1961 and 2018. The dataset includes comprehensive details such as witness names, organizational affiliations, hearing summaries, committee titles, dates, and bill numbers discussed. The chapter describes the meticulous construction process, emphasizing the extraction of key variables focusing on witness affiliations, affiliation type, and gender. With eighteen categorized affiliation types and nine broader parent categories, this classification captures the diverse spectrum of external groups represented in congressional hearings. The chapter also provides rich descriptive statistics on hearings and witness over time and across committees.

Chapter 5 examines the intent for a legislative hearing and how it affects a committee’s selection of witnesses. Committees, guided by the partisan goals of the committee chair, seek different types of information depending on whether they are considering specific bills in hearings. When the chair has not yet advanced a bill through the committee process, it gives the committee more political flexibility to hear from those who can provide expertise in policy development. Consistent with this argument, we show that committees turned to think tanks, universities, and bureaucrats – witnesses who can provide more analytical information – at higher rates for hearings without a bill (nonreferral hearings), when committees hearings to learn about an issue area. Committees tended to invite witnesses from mass-based groups, such as labor unions, trade associations, and membership associations, at higher rates for hearings on a specific bill (referral hearings). Different witness compositions between referral and nonreferral hearings suggest strategic choices of the identities of witnesses and thus the types of information that the committee hearing generates.

This chapter outlines our book’s contributions to understanding how partisan incentives drive the information-seeking behavior of Congress and its committees. Moreover, it underscores the challenge legislators face in balancing their political roles with the need for expert insights. In this final chapter, we relate our arguments and findings to recent challenges Congress has faced in seeking information in its partisan environment. We propose new lines of research that build on our data and work in our book and emphasize the connections to long-standing issues in American democracy. Our book, empirical evidence, and accompanying analyses promote a new understanding of the dynamics underlying the acquisition and dissemination of information in Congress and, we hope, will stimulate further inquiry into the role of information in shaping public policy in a democracy.

Chapter 2 delves into the critical role of congressional hearings and witnesses during the committee stage, emphasizing their significance in shaping legislative outcomes and policy formulation. It explores how hearings serve as one of the prime avenues for information gathering, drawing from previous studies to highlight their impact on communication among legislators, interest groups, and bureaucrats. The chapter unpacks the intricate process of selecting witnesses, elucidating the process of inviting individuals who provide members of Congress information during the committee stage. It underscores the choices and variables present in this selection process – such as expertise, ideological leaning, and organizational affiliations. Ultimately, this chapter serves as a comprehensive primer on the process of witness selection for congressional hearings and describes the pivotal role played by witnesses in a key stage of policymaking.