Title: Judging Ideology
Description: This dissertation is motivated by a straightforward question about a drastic change to American politics: why has the process of staffing the circuit courts of appeals, once so agreeable and bipartisan, seemed to have descended into almost complete partisan bitterness? Across the entire time series, these are, after all, the same courts endowed with the same power of judicial review. And when the process of staffing them was harmonious, the courts were nevertheless deciding the fate of major, controversial policies of national importance---such as the New Deal in the 1930s and civil rights in the 1950s---just as they do today. Yes, many other aspects of American politics have changed through the decades. But what could possibly explain such a complete reversal of course? I argue that this change, toward divisiveness and partisan warfare, is actually about the judiciary itself and the substantive manner by which the nominees are thought of---namely, the entry of judicial ideology into the debate through the innovation of circuit judges being evaluated on ideological terms.

While taken for granted as central today, any ideological assessment of circuit court nominees, and in particular viewing them as having a comprehensive judicial philosophy as opposed to just a position on singular pressing issue of the day, was almost nonexistent for generations. Its entry into the process was piecemeal and somewhat complicated, but it eventually came to dominate and irrevocably polarize the business of staffing the courts. I argue that this was the key factor that leaves us where we are today. Broadly speaking, I consider the contributions and particular strengths of my dissertation, relative to previous scholarship, to be threefold. First is my argument and accompanying analyses which put the crucial (and severely understudied) role of judicial ideology front and center. Second, I analyze the entire lifespan of the circuit courts, whereas the previous scholarship looks only at (often relatively brief) subsets of their history. As far as I know, this is the first study to systematically look at all circuit court nominations from the establishment of these courts in 1891 through the modern era.

Third, I collect and analyze a great deal of new data. In particular I focus on systematically utilizing extensive archival resources and build two original data sets related to the Senate's public and private evaluation of judicial nominees; and while there is certainly a qualitative aspect to much of this research, I also synthesize and make sense of it with quantitative analysis. In chapter 1, I explain the puzzle motivating this research, elaborate my argument, and lay out the theoretical, methodological, and data collection contributions of this dissertation. I also review the literature and describe the three existing schools of thought. In chapter 2, I give an overview of the history of the circuit courts from their founding to the present. In this data-heavy chapter, I examine multiple metrics individually, and using several of these I build a robust composite score of divisiveness for each nominee ever made to the circuit courts, from 1891 through 2020. As far as I know this has never been done before.

I find overwhelming evidence that the process has fundamentally changed and become more divisive. In chapter 3, I dig more deeply into the timing of this change, and begin to explore how and why it happened---and begin my attempt at demonstrating how the evaluation of judicial ideology is central to this change. To do this I examine a massive data source that has never been utilized: the Senate Judiciary Committee hearings for all nominees. With both qualitative and quantitative analysis, I show that the evaluation of nominees has varied widely over time. Prior to 1979, nominees were evaluated almost exclusively based on their qualifications, with ideology examined only under special circumstances, which I explore in depth. In this time period, ideological scrutiny predicted a contentious confirmation process, providing evidence for my argument that ideological evaluation drove divisiveness. Also in this chapter, I analyze the post-1979 transition to the routine ideological evaluation that permanently altered the confirmation process.

I find that Republicans and comprehensive judicial philosophies both played a key role. In chapter 4, I examine the senators' private evaluation of nominees, in part to serve as a check on the validity of my earlier data analysis and also to see if there is any difference between the senators' public and private goals in relation to the judiciary. To do this, I build an original data set of over 1000 internal letters and memoranda from senators, by searching the archival records of nearly every president since Benjamin Harrison as well as over 150 senators. Studying this material qualitatively and quantitatively, the findings here largely align with the analysis of the public committee hearings: for much of history senators were concerned mainly about qualifications, with ideological concern rare and under special circumstances, but eventually ideology came to be the predominant concern which ended the consensual and placid process. This immense historical record also brings to light additional senatorial goals, such as ensuring residents of their own state as well as personal friends obtain judicial appointments.

In chapter 5, I focus in on the post-1979 era and I find that the more ideologically distant a nominee is from the Senate, the more divisive the confirmation process is. This provides evidence that the process is defined by ideology related to the nominees, not garden variety polarization of the system. In chapter 6, I conclude, trying to synthesize all of my findings as well as offer some thoughts on areas of future research.