Does unconscious racial bias affect trial judges?

Author:Rachlinski, Jeffrey J.

Race matters in the criminal justice system. Black defendants appear to fare worse than similarly situated white defendants. Why? Implicit bias is one possibility. Researchers, using a well-known measure called the Implicit Association Test, have found that most white Americans harbor implicit bias toward black Americans. Do judges, who are professionally committed to egalitarian norms, hold these same implicit biases? And if so, do these biases account for racially disparate outcomes in the criminal justice system? We explored these two research questions in a multi-part study involving a large sample of trial judges drawn from around the country. Our results--which are both discouraging and encouraging--raise profound issues for courts and society. We find that judges harbor the same kinds of implicit biases as others; that these biases can influence their judgment; but that given sufficient motivation, judges can compensate for the influence of these biases.


Justice is not blind.

Researchers have found that black defendants fare worse in court than do their white counterparts. In a study of bail-setting in Connecticut, for example, Ian Ayres and Joel Waldfogel found that judges set bail at amounts that were twenty-five percent higher for black defendants than for similarly situated white defendants. (1) In an analysis of judicial decisionmaking under the Sentencing Reform Act of 1984, David Mustard found that federal judges imposed sentences on black Americans that were twelve percent longer than those imposed on comparable white defendants. (2) Finally, research on capital punishment shows that "killers of White victims are more likely to be sentenced to death than are killers of Black victims" and that "Black defendants are more likely than White defendants" to receive the death penalty. (3)

Understanding why racial disparities like these and others persist in the criminal justice system is vital. Only if we understand why black defendants fare less well than similarly situated white defendants can we determine how to address this deeply troubling problem.

Two potential sources of disparate treatment in court are explicit bias and implicit bias. (4) By explicit bias, we mean the kinds of bias that people knowingly--sometimes openly--embrace. Explicit bias exists and undoubtedly accounts for many of the racial disparities in the criminal justice system, but it is unlikely to be the sole culprit. Researchers have found a marked decline in explicit bias over time, even as disparities in outcomes persist. (5)

Implicit bias--by which we mean stereotypical associations so subtle that people who hold them might not even be aware of them--also appears to be an important source of racial disparities in the criminal justice system. (6) Researchers have found that most people, even those who embrace nondiscrimination norms, hold implicit biases that might lead them to treat black Americans in discriminatory ways. (7) If implicit bias is as common among judges as it is among the rest of the population, it might even account for more of the racially disparate outcomes in the criminal justice system than explicit bias.

In this Article, we report the results of the first study of implicit racial bias among judges. We set out to explore whether judges hold implicit biases to the same extent the general population and to determine whether those biases correlate with their decisionmaking in court. Our results are both alarming and heartening:

(1) Judges hold implicit racial biases.

(2) These biases can influence their judgment.

(3) Judges can, at least in some instances, compensate for their implicit biases.

Our Article proceeds as follows. We begin, in Part I, by introducing the research on implicit bias and its impact on behavior. In Part II, we briefly describe the methods of our study. We provide a much more detailed account in the Appendix. In Part III, we report our results and interpret them. Finally, in Part IV, we explore the implications of our results for the criminal justice system, identifying several possible measures for combating implicit racial bias.


    Psychologists have proposed that implicit biases might be responsible for many of the continuing racial disparities in society. (8) To assess the extent to which implicit biases account for racial disparities, researchers must first ascertain whether people hold implicit biases and then determine the extent to which implicit biases influence their actions.

    1. Demonstrating Implicit Bias

      In their efforts to assess whether people harbor implicit biases, psychologists have used a variety of methods. (9) Standing front and center among these methods, however, is the Implicit Association Test (IAT). (10) Developed by a research group led largely by Tony Greenwald, Mahzarin Banaji, and Brian Nosek, the IAT is the product of decades of research on the study of bias and stereotypes (11) and has attracted enormous scholarly and popular attention. (12) More than four and a half million people have taken the IAT. (13) The test takes different forms, but most commonly, it consists of a computer-based sorting task in which study participants pair words and faces. A typical administration of the "Race IAT" proceeds as follows (14):

      First, researchers present participants with a computer screen that has the words "White or Good" in the upper left-hand corner of the screen and "Black or Bad" in the tipper right. The researchers then inform the participants that one of four types of stimuli will appear in the center of the screen: white people's faces, black people's faces, good (positive) words, or bad (negative) words. The researchers then explain that the participants should press a designated key on the left side of the computer when a white face or a good word appears and press a designated key oil the right side of the computer when a black face or a bad word appears. Researchers refer to the white/good and black/bad pairings as "stereotype congruent," because they are consistent with negative stereotypes associated with black Americans. (15) The participants complete several trials of this first task.

      Then, the computer is programmed to switch the spatial location of "good" and "bad" so that the words "White or Bad" appear in the upper left-hand corner and "Black or Good" appear in the upper right. The researchers explain to the participants that they are now supposed to press a designated key on the left side of the keyboard when a white face or a bad word appears and press a designated key on the right side of the keyboard when a black face or a good word appears. Researchers refer to these white/bad and black/good pairings as "stereotype-incongruent," because they are inconsistent with the negative stereotypes associated with black Americans. The participants then complete several trials of this second task. (16)

      Researchers have consistently found that white Americans express a strong "white preference" on the IAT. (17) They make this determination by comparing the amount of time it takes respondents to complete the two tasks identified above--that is, their "response latency." (18) Most white Americans complete the first task (in which they sort white and good from black and bad) more quickly than the second (in which they sort black and good from white and bad). (19) In other words, most white Americans produce higher response latencies when faced with the stereotype-incongruent pairing (white/bad or black/good) than when faced with the stereotype-congruent pairing (white/good or black/bad).

      Researchers have observed a different pattern of implicit biases among black Americans. Black Americans do not exhibit the same white preference that whites express, but neither do they show a mirror-image black preference. (20) Rather, black Americans express a much greater variation, with many expressing moderate to strong black preferences that are rarely found in white Americans. (21) But some also express white preferences--sometimes even strong ones. (22) On average, black Americans express a slight white preference, but the average masks wide variation in response. (23) Latinos also express a small white preference. Asian Americans show a white preference that is comparable to but somewhat weaker than that found in white Americans. (24)

      The implications of the research using the IAT are a matter of some debate, (25) but the cognitive mechanisms underlying the research are clear enough. The white preference arises from well-established mnemonic links. Whites more closely associate white faces with positive words and black faces with negative words than the opposite. Thus, when they complete the white/good versus black/bad trials, they need only make a judgment about whether the stimulus that appears in the middle of the screen is positive or negative. The incongruent association, in contrast, requires that they first judge whether the stimulus is a word or a face and then decide on which side it belongs. Stereotype-incongruent associations interfere with the sorting task in much the same way that the use of green ink can make the word "blue" hard to read. (26)

      The white preference on the IAT is well-documented among white Americans. (27) Researchers have conducted and published hundreds of academic studies, and several million people have participated in IAT research. (28) They have determined that the implicit biases documented through IAT research are not the product of the order in which people undertake the tasks, their handedness, or any other artifact of the experimental method. (29) The prevailing wisdom is that IAT scores reveal implicit or unconscious bias. (30)

    2. Implicit Bias and Behavior

      Even if implicit bias is as widespread as the IAT studies suggest, it does not necessarily lead to, or explain, racially disparate treatment. Only if researchers can show that implicit bias influences decisionmakers can we infer...

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