We present a new measure of judicial ideology based on judicial hiring behavior. Specifically, we utilize the ideology of the law clerks hired by federal judges to estimate the ideology of the judges themselves. These Clerk-Based Ideology (CBI) scores complement existing measures of judicial ideology in several ways. First, CBI scores can be estimated for judges across the federal judicial hierarchy. Second, CBI scores can capture temporal changes in ideology. Third, CBI scores avoid case selection and strategic behavior concerns that plague existing vote-based measures. We illustrate the promise of CBI scores through a number of applications.

We study the political ideology of judicial law clerks in the United States, by constructing a novel dataset that combines information on the identity of clerks with a measure of political ideology based on political donations. We then use this data to empirically investigate several important questions about the ideologies of clerks. First, we examine whether clerks tend to share the liberal ideology of other lawyers or the more conservative ideology associated with federal judges and find that clerks tend to be disproportionately liberal. Second, we investigate how the ideology of clerks compares to the ideology of lawyers and find that liberal lawyers are more likely to have clerked than conservatives. Third, we assess whether the ideology of clerks differs based on the level of clerkship and find that the liberal skew becomes less pronounced as the prestige of the clerkship increases. Fourth, we analyze how ideology influences the hiring of clerks and find that the ideology of judges is strongly correlated with the ideology of their clerks.

We extend the scaling methodology previously used in Bonica (2014) to jointly scale the American federal judiciary and legal profession in a common-space with other political actors. The end result is the first data set of consistently measured ideological scores across all tiers of the federal judiciary and the legal profession, including 840 federal judges and 380,307 attorneys. To illustrate these measures, we present two examples involving the U.S. Supreme Court. These data open up significant areas of scholarly inquiry.

How do Americans evaluate potential U.S. Supreme Court candidates? Using a novel, two-part conjoint experiment, I show that respondents put high importance on the political leanings of potential Court candidates, a finding in contrast with the scholarly view that the public views the Court as different from other, more political institutions. Indeed, when respondents are given information about a nominee’s partisan leanings they rely extensively on that information in de- ciding whether to support the candidate, whether they trust the candidate, and whether they find the candidate qualified. By contrast, when partisan information is withheld, respondents appear to use other kinds of signals, such as race, in order to fill in the gaps. Those who are most knowledgeable about the Court are most influenced by these partisan signals, providing further support for the importance of political heuristics. The results suggest that the public’s evaluation of judicial nominees is more in line with how it evaluates other political actors. They also suggest that even candidates with excellent qualifications need not garner bipartisan public support.

Using a new dataset capturing the ideological positioning of nearly half a million U.S. judges and lawyers, we present evidence showing how ideology affects the selection of judges across federal and state judiciaries. We document that the higher the court, the more it deviates ideologically from the ideology of attorneys, suggesting ideology plays a strong role in judicial selection. We also show ideology plays stronger roles in jurisdictions where judges are selected via political appointments or partisan elections. Our findings suggest that ideology is an important component of judicial selection primarily where (1) using ideology leads to expected benefits to politicians, (2) when the jurisdiction's selection process allows ideology to be used, and (3) where it concerns the most important courts. The study is the first to provide a direct ideological comparison across judicial tiers and between judges and lawyers and to explain how and why American courts become politicized.

Judicial nominees to federal courts rarely reveal their genuine views on controversial issues. As a result, political actors---and especially the Senate---often have only partial information about how a nominee would vote on issues likely to come before the courts. We formulate a model that departs from the previous literature by incorporating this type of uncertainty into the nominations process. Our model shows that the absence of such information can yield suboptimal outcomes. In particular, when the President and Senate are ideologically divergent, low information about nominees' views results in the Senate occasionally rejecting acceptable nominees. Thus, even though low information allows the President to ``sneak in" more extreme candidates, it leads to both the President and the Senate being worse off than they would be with more transparency. Under such conditions, more information weakly increases both sides' welfare. Our results therefore raise questions about why nominees are permitted to keep important views private.

Does encouragement help address gender imbalances in technical fields? We present the results of one of the first and largest randomized controlled trials on the topic. Using an applied statistics conference in the social sciences as our context, we randomly assigned half of a pool of 3,945 graduate students to receive two personalized emails encouraging them to apply (n = 1,976) and the other half to receive nothing (n = 1,969). We find a robust, positive effect associated with this simple intervention and suggestive evidence that women responded more strongly than men. However, we find that women’s conference acceptance rates are higher within the control group than in the treated group. This is not the case for men. The reason appears to be that female applicants in the treated group solicited supporting letters at lower rates. Our findings therefore suggest that “low dose” interventions may promote diversity in STEM fields but may also have the potential to expose underlying disparities when used alone or in a non-targeted way.

The ideology of American lawyers has been a persistent source of discussion and debate. Two obstacles, however, have prevented this topic from being systematically studied: the sheer number of attorneys in the USA and the need for a methodology that makes comparing the ideology of specific individuals possible. In this article, we present a comprehensive mapping of lawyers’ ideologies that has overcome these hurdles. We use a new dataset that links the largest database of political ideology with the largest database of lawyers’ identities to complete the most extensive analysis of the political ideology of American lawyers ever conducted.

Although understanding the role of race, ethnicity, and identity is central to political science, methodological debates persist about whether it is possible to estimate the effect of something ``immutable.'' At the heart of the debate is an older theoretical question: is race best understood under an essentialist or constructivist framework? In contrast to the ``immutable characteristics'' or essentialist approach, we argue that race should be operationalized as a ``bundle of sticks'' that can be disaggregated into elements. With elements of race, causal claims may be possible using two designs: (1) studies that measure the effect of exposure to a racial cue and (2) studies that exploit within-group variation to measure the effect of some manipulable element. These designs can reconcile scholarship on race and causation and offer a clear framework for future research.

Researchers seeking to establish causal relationships frequently control for variables on the purported causal pathway, checking whether the original treatment effect then disappears. Unfortunately, this common approach may lead to biased estimates. In this paper, we show that the bias can be avoided by focusing on a quantity of interest called the controlled direct effect. Under certain conditions, the controlled direct effect enables researchers to rule out competing explanations---an important objective for political scientists.  To estimate the controlled direct effect without bias, we describe an easy-to-implement estimation strategy from the biostatistics literature. We extend this approach by deriving a consistent variance estimator and demonstrating how to conduct a sensitivity analysis. Two examples---one on ethnic fractionalization's effect on civil war and one on the impact of historical plough use on contemporary female political participation---illustrate the framework and methodology.

We show that contemporary differences in political attitudes across counties in the American South in part trace their origins to slavery’s prevalence more than 150 years ago. Whites who currently live in Southern counties that had high shares of slaves in 1860 are more likely to identify as a Republican, oppose affirmative action, and express racial resentment and colder feelings toward blacks. We show that these results cannot be explained by existing theories, including the theory of contemporary racial threat. To explain the results, we offer evidence for a new theory involving the historical persistence of political attitudes. Following the Civil War, Southern whites faced political and economic incentives to reinforce existing racist norms and institutions to maintain control over the newly freed African American population. This amplified local differences in racially conservative political attitudes, which in turn have been passed down locally across generations.

Why do some countries incorporate language from international treaties into their constitutions? Why do others not do so? This is among the most important questions in international law as well as the focus of Versteeg’s (2015) thought-provoking article “Law versus Norms: The Impact of Human-Rights Treaties on National Bills of Rights.” Versteeg’s data, among the most original and important in this field, lead us to think that treaties affect both norms and laws, which in turn affect constitutional language development. Building from this work, I advocate that scholars ought to think carefully about the complicated counterfactuals and causal processes behind the process of constitutional language change and to engage further the observational implications of the explanation in terms of norms versus those in terms of institutions. Thinking more carefully about the causal pathways, as well as the appropriate counterfactuals, could open up important avenues for exploring possible mechanisms for domestic constitutions to be affected by international treaties.

We begin with a typology of Americans’ understanding of the links between genetic inheritance and racial or ethnic groups. The typology has two dimensions: one running from genetic determinism to social construction, and the other from technology optimism to technology pessimism. Construing each dimension as a dichotomy enables four distinct political perspectives on the possibilities for reducing racial inequality in the United States through genomics. We then use a new public opinion survey to analyze Americans’ use of the typology. Survey respondents who perceive that some phenotypes are more prevalent in one group than another due to genetic factors are disproportionately technology optimists. Republicans and Democrats are equally likely to hold that set of views, as are self-identified blacks, whites, and Latinos. The article discusses the findings and speculates about alternative interpretations of the fact that partisanship and group identity do not differentiate Americans in their views of the links between genetic inheritance and racial inequality.

Experts, like lay people, express varying levels of technology optimism or pessimism about scientific endeavors. However, explanations for this variation are underdeveloped. We explore technology optimism and pessimism among experts, who have high levels of scientific literacy but different values and norms. We focus on genomic science; its novelty, life-and-death implications, complex technology, and broad but as-yet-unknown societal implications make it an excellent subject for the study of views about new knowledge. After demonstrating the range of views through elite interviews, we analyze results of two content analyses of about 750 articles by prominent social scientists, law professors, and biologists. Some disciplines pay more attention to genomics than others, and they differ in their valences; experts in more liberal disciplines tend to be less optimistic about genomics than scholars in relatively more conservative disciplines. We speculate on why genomics is an exception to the general finding that liberals are more supportive of science than conservatives.

In this paper, I use two new data sets to demonstrate that black federal judges are consistently overturned on appeal more often than similar white judges. The effect is robust and persists after taking into account previous professional and judicial experience, educational backgrounds, qualification ratings assigned by the American Bar Association, and differences in partisanship. This study is the first to explore how higher-court judges evaluate opinions written by judges of color, and it has clear implications: despite attempts to make judiciary more reflective of the general population, racial disparities within the legal system continue to persist.

In this paper, we ask whether personal relationships can affect the way that judges decide cases. To do so, we leverage the natural experiment of a child's gender to identify the effect of having daughters on the votes of judges. Using new data on the family lives of U.S. Courts of Appeals judges, we find that, conditional on the number of children a judge has, judges with daughters consistently vote in a more feminist fashion on gender issues than judges who have only sons. This result survives a number of robustness tests and appears to be driven primarily by Republican judges. More broadly, this result demonstrates that personal experiences influence how judges make decisions, and it is the first paper to show that empathy may indeed be a component in how judges decide cases.

Recent studies have questioned whether American Bar Association (ABA) ratings of judicial nominees are skewed against minority candidates.  However, a strong critique of these findings is that they are being driven by appointments made at a time of greater inequality in terms of education and preparedness.  In this paper, I address these questions.  First, I provide evidence that the educational and professional backgrounds of minority judicial nominees have indeed shifted over time, and that minority judges increasingly attend prestigious law schools and have clerkship experience.  Second, however, I show that the gap in ABA ratings between minority and white candidates continues into recent years, despite this trend.  My results therefore contribute to a growing literature calling into question the ongoing use of subjective ratings of judicial candidates.

This paper uses two new datasets to investigate the reliance by political actors on the external vetting of judicial candidates, in particular vetting conducted by the nation's largest legal organization, the American Bar Association (ABA). First, I demonstrate that poorly rated lower-court nominees are significantly more likely to have their nominations fail before the Senate. However, I also show that minority and female nominees are more likely than whites and males to receive these lower ratings, even after controlling for education, experience, and partisanship via matching. Furthermore, by presenting results showing that ABA ratings are unrelated to judges' ultimate reversal rates, I show that these scores are a poor predictor of how nominees perform once confirmed. The findings in this paper complicate the ABA's influential role in judicial nominations, both in terms of its utility in predicting judicial "performance" and also in terms of possible implicit biases against minority candidates, and suggest that political actors rely on these ratings perhaps for reasons unrelated to the courts.