Studying traffic stop encounters

Racial profiling has received significant consideration in recent years as politicians, police, academics, the media, advocacy groups, and the general public attempt to understand and assess the extent to which this practice occurs in the nation. Despite considerable attention and the investment of substantial financial resources, the question of whether racial profiling exists has eluded a conclusive answer. As more efforts are made to study police traffic stop data, it is crucial that researchers have an understanding of the associated methodological issues. This article considers traffic stop studies from a methodological perspective, discussing the challenges associated with conducting meaningful research of police officer decision making patterns in traffic stop encounters. Using data from a Midwestern community, as well as the experiences of researchers across the country, the authors illustrate and discuss implications for data collection, variables, and data analysis.     

Testing the racial profiling hypothesis for seemingly disparate traffic stops on the New Jersey Turnpike

This paper describes two studies designed to produce benchmark values with which to compare police stop data in an effort to assess racial profiling. Racial profiling is often measured by comparing the racial and ethnic distribution from police stop rates to race and ethnicity data derived from regional census counts. However, benchmarks may be more appropriate that are based on (1) the population of drivers or (2) the population of traffic violators. This research surveyed drivers on the New Jersey Turnpike and produced benchmark distributions reflecting these two populations. Benchmark values then were compared to police stops collected from State Troopers patrolling the Turnpike. The results revealed that the racial make‐up of speeders differed from that of nonspeeding drivers and closely approximated the racial composition of police stops. Specifically, the proportion of speeding drivers who were identified as Black mirrored the proportion of Black drivers stopped by police. This finding may explain the differences found between police stop rates and regional census data that are often interpreted as evidence of racial profiling. Interpretation and limitations of the results are discussed.     

Examining the influence of drivers' characteristics during traffic stops with police: Results from a national survey

The factors that influence officer decision making after a traffic stop is initiated are examined using the Police-Public Contact Survey data collected in 1999. This investigation of police behavior is framed with an understanding of the organizational roots of racial profiling tactics and policies. The findings show that young black and Hispanic males are at increased risk for citations, searches, arrests, and uses of force after other extralegal and legal characteristics are controlled. Additional analyses show that minority drivers are not, however, more likely to be carrying contraband than are white drivers. The implications for policy and future research are discussed.     

Searching for direction: Courts,social science,and the adjudication of racial profiling claims

As an issue of contemporary legal and social concern, racial profiling has become part of the national discourse. As claims of racial profiling proliferate, courts are struggling to adjudicate them without sound social science research on law enforcement stop practices. This article reviews the methodological and analytical weaknesses inherent in most of the research on racial profiling and illustrates how these weaknesses have caused problems for courts in deciding racial profiling claims. It also presents a methodological strategy for curing many of the defects in previous racial profiling studies, thereby providing courts with a sound basis for deciding equal protection-based claims that often rely on statistical evidence.     

Theory and racial profiling: Shortcomings and future directions in research

The volatile political environment that surrounds the issue of “racial profiling” has led local and state police agencies across the nation to start collecting information about traffic and pedestrian stops. The controversy over this issue is overwhelmed by the unsupported assumption that all race-based decision making by police officers is motivated by individual police officers' racial prejudice. This article reviews recently published studies on racial profiling and critiques both their methods and conclusions. Using the conceptual framework for police research presented by Bernard and Engel, it reviews a number of theories that may explain racial disparities in the rates of police stops. The authors argue that to explain police behavior better, theoretical models must guide future data collection efforts.     

Race matters: A critical look at racial profiling, it's a matter for the courts

The disproportionate number of minority motorists stopped by the police gives rise to a host of salient questions which center on contemporary police practices. Research has shown that traffic stops are routinely used as a “pretext” to stop minority drivers. In this article, the authors argue that the current police practice of disproportionately stopping minority motorists was formally sanctioned by the Supreme Court in Whren v. United States (1996). The current thrust to examine police practices will do little to end racial profiling, and the underpinnings of this problem, in part, lie in judicial precedent. The authors present the notion that in order to minimize racial profiling, the court must carve out an objective test from the Whren decision that will guide police behavior in the pretextual stops of motorists. The article concludes with a template of what this objective test may look like.     

Race and place: The ecology of racial profiling African American motorists

We propose an ecological dimension to racial profiling by comparing the distribution of drivers on the roadways with officers' proactive surveillance and stop behavior in a predominantly white suburban community bordering a predominantly African American community. African Americans are subject to significant racial profiling, as reflected in disproportionate surveillance and stopping by the police when driving through whiter areas. Officers' behavior is not explained by African Americans' criminality because the “hit rates” for African American drivers are lower in white areas. Profiling is sensitive to race and place and manifests itself organizationally, reflecting community patterns of residential segregation.     

Assessing the Effect of Race Bias in Post-traffic Stop Outcomes Using Propensity Scores

   In response to community demands, case settlements, and state laws concerning racial profiling, police departments across the nation are collecting data on traffic stops. While the data collection is rapidly moving forward, there are few if any agreed upon methods for analyzing the data. Much of the attention has been on benchmarks for the race distribution of stops and searches. Little empirical work has advanced our understanding of the influence of race in the post-stop activities of police. The present study proposes a propensity score technique to determine the extent to which race bias affects citation rates, search rates, and the duration of the stop. Adjusting for confounding variables using the propensity score offers an alternative to multivariate regression that is more interpretable, less prone to errors in model assumptions, and ultimately easier to present to stakeholders in policing practices. An analysis of traffic stop data from the City of Oakland, California demonstrates the process, presentation, and interpretation of the results that the methodology produces. Ultimately, the study addresses the extent to which race plays a role in officers’ use of discretion.

PERCEPTIONS OF RACIAL PROFILING: RACE,CLASS, AND PERSONAL EXPERIENCE*

Racial profiling by the police has become an increasingly controversial issue in recent years, but we know little about the extent of the problem and even less about public perceptions of profiling. This article analyzes recent national survey data on citizens' views of racial profiling. We find that both race and personal experience with profiling are strong predictors of attitudes toward profiling and that, among blacks, social class affects views of the prevalence and acceptability of the practice. The findings on social class point to the need for further investigation and explanation of class influences on evaluations of the police.     

The methodological struggles of racial profiling research: a causal question that automobile stop data has yet to answer

Automobile stop research finds that citizen race influences officer decision-making. Researchers, however, report methodological issues inhibiting them from drawing causal inferences about the existence of racial profiling. The purpose of this study is to deconstruct this field of inquiry through a causal lens to inform the next generation of scholarship. Through an analysis of automobile stop data, temporal ordering issues are exposed. Relating to association, most studies find that racial minorities are more likely to be searched, however, spuriousness issues continue to plague racial profiling studies as researchers rarely estimate departmental, passenger, vehicle, and temporal variables. To confront these issues, researchers are encouraged to engage in primary data collection and explore recent statistical innovations in their analytical strategies.     

POLICING RACE: THE RACIAL STRATIFICATION OF SEARCHES IN POLICE TRAFFIC STOPS*

Research on race effects in police traffic stops is theoretically underdeveloped. In this study, we derive propositions from Donald Black's theory of law to explain the interaction effects of officer and driver race on searches in traffic stops in St. Louis, Missouri. Our citywide results and those for stops in predominantly White communities are generally consistent with the theory: Searches are more likely in stops of Black drivers than in those of White drivers, especially by White officers, controlling for other characteristics of the officer, driver, and stop. In predominantly Black communities, however, stops of White drivers by White officers are most likely to result in a search. We interpret both sets of results as manifestations of racial profiling in segregated communities and suggest that Black's theory of law remains a promising theoretical framework for future research on the continuing significance of race‐based policing in the United States.     

The verdict is in: how did they decide? Using drivers’ self-reported data to understand officers’ decision making during traffic stop encounters

ABSTRACT

In the United States, traffic stop is the most common form of police-citizen encounter, and for many citizens, it is the only way they will ever interact with the police. The frequency of traffic stop encounters has therefore attracted a significant research interest. In the past several years, researchers have attempted to explain the dynamics of these interactions, with the hope to change attitudes and influence policy formation. To supplement the efforts of previous researchers, the current effort analyzed self-reported data from citizens to understand police decision making at three decision points during traffic stop encounters. Specifically, the present study aims to answer three questions: what variables predict whether an officer will let a citizen go without doing anything or decide to do something? If the officer decides to do something, what influences the officer’s decision to choose an outcome over others? What are the drivers of use of force in traffic stop encounters? Results from the regression models suggest that reasons for the stop, verbal assault, officer and suspect characteristics are important predictors of police decision making behavior during traffic stop interaction. The findings have serious implications for developing better police-citizen relationships as well as improving public attitudes toward the local police.     

Race, driving, and police organization: Modeling moving and nonmoving traffic stops with citizen self-reports of driving practices

A rapidly growing body of police scholarship has found evidence of racial disparities in traffic stop patterns using police-generated data. Despite the empirical consensus, the question of whether race inappropriately influences traffic stop patterns remains open, largely as a result of methodological weaknesses. The current article helps to address this issue by employing self-report data about citizens' driving practices and traffic stops. It presents a series of models that predict the likelihood of a self-reported traffic stop disaggregated by police organizational type and the reason for the stop. Results suggest that moving and nonmoving driving practices are associated with the likelihood of police stops for moving and nonmoving reasons, respectively. As expected, differences between local police and state police models emerge. Finally, Black drivers and younger drivers are especially vulnerable to traffic stop risk for nonmoving stops by local police, even after controlling for driving behaviors.     

Police leniency in traffic enforcement encounters: Exploratory findings from observations and interviews

Despite the volume of time officers spend on traffic enforcement encounters, there was limited research exploring how they used their discretion in such interactions. Issues relating to police decision making patterns in the enforcement of motor vehicle laws were particularly salient in light of the on-going debate over racial profiling. This study examined how officers made decisions (in particular, to stop and to sanction) in the course of traffic enforcement. Using field observations and interviews with officers in a small midwestern agency, the authors described the factors and forces that officers used in making discretionary choices. The findings indicated that leniency in sanctioning was very common and that officers expected citizens to be contrite and acknowledge responsibility for their infractions. Implications for larger and more systematic observational studies are discussed.     

How Do the Laws of Probability Constrain Legislative and Judicial Efforts to Stop Racial Profiling?

Faced with pending legislation and litigation, numerous jurisdictionshave begun programs to monitor a range of traffic stop outcomes,focusing on variation by race or ethnicity. Existing programs,however, ignore the unequal outcomes that motivate oppositionto racial profiling. Statistical relationships limit the abilityof public policy to equalize the various outcomes, even if officersdo not engage in racial profiling to "any extent or degree."This article demonstrates relationships among five outcomesthat are or should be considered when policy on racial profilingis formulated: search rates, find rates, thoroughness of search,rates of detention of the innocent, and rates of apprehensionof the guilty. Once decisions are made as to how to balancedesires for equality of each of these outcomes, problems remainthat are common to statistical assessments of pattern- or practice-of-discriminationclaims.     

Repeat Citizens in Motor Vehicle Stops

ABSTRACT

This paper explores the possible existence of the repeat phenomenon and their impact on racial disparities in police motor vehicle stops. The repeat phenomenon is the existence of a small proportion of people or places that account for a much larger proportion of events. While this phenomenon has been identified and discussed in other areas of criminal justice and criminology, it has not been extended to motor vehicle stops. The current study examines the existence of repeat citizens in a population of motor vehicle stops (N = 4775) from a Mid-western city during 2001. A small, but significant, concentration of motor vehicle stops were discovered among a few citizens and significant predictors of citizen performance included citizen race, gender, age, residency, time of the stop, and reason for the stop.     

Police Misconduct,Media Coverage,and Public Perceptions of Racial Profiling: An Experiment

The purpose of this study was: (1) to assess the impact of an incident of racial profiling on residents’ attitudes about profiling; and (2) to examine the effects of exposure to a video clip of deliberation about the incident on residents’ beliefs about the causes of profiling. All residents, White and minority, were less likely to believe that Chicago police officers engaged in profiling after the incident. These findings suggest that attitudes about the prevalence of racial profiling are susceptible to the manner in which the media construct incidents of police misconduct. Exposure to the video clip was not related to differences in residents’ beliefs about the causes of profiling, but was related to differences in perceptions of the dangerousness of traffic stops. The findings highlight the need for more research on how media constructions of police misconduct influence attitudes about profiling and impact community–police relations.     

On terror, drugs and racial profiling

We show that for racial profiling (defined as policy rules that employ statistical discrimination based on racial attributes) to be efficient in fighting ordinary crime, it needs to focus on the racial composition of marginal offenders. Efficiency thus may counter-intuitively call for targeting the group with the lower offending rates. In the context of terror, however, it has to be based primarily on differences in offending rates across racial population groups (group-wise averages). We demonstrate that, assuming correlation between race and crime, racial profiling would nearly always be efficient. Finally, we discuss equity considerations and suggest that if awarding compensation is perceived to be a viable policy option, it should be paid on an ex ante basis.     

Lines and shadows: Perceptions of racial profiling and the Hispanic experience

Despite a longstanding research tradition examining the intersection of policing and race, extant research focused almost exclusively on race and ethnicity in Black and White terms. As such, academic knowledge of the Hispanic experience remained opaque. In this study, data from a random sample of New York City residents were used to compare the perceptions of racial profiling among Hispanic and non-Hispanic citizens. In particular, factors relating to the perception that racial profiling was widespread, justified, and personally experienced were examined. Findings were grounded within the literature on police-citizen relations and racial profiling.     

‘Inappropriate but not crime’? Policing racial hatred in Sweden

ABSTRACT

Racial bias afflicts police practices across the globe. Police discrimination against and mistreatment of racial and ethnic minorities is indeed difficult to underestimate. While much attention has been thus paid to racially biased policing, fewer studies examine the question from the reverse angle, namely how the police themselves combat racist offences. This article offers empirical insights into the policing of racial hatred in Sweden, a relevant yet relatively understudied case. Drawing on interviews with police officers and crime investigators, I discuss law enforcement perspectives, e.g. perceptions and reasoning in relation to the investigation of racist offences. Findings evince a rather narrow approach as regards the constructions of racist motive that involves a relatively restricted use of bias labelling in identifying hate incidents, especially when the boundaries of racial hostility are perceived as blurred. I argue that while such an approach may reflect a legitimate effort to demonstrate the existence of a motive behind an offence, it may also lead to an underestimation of more mundane forms of racism and their harms inflicted upon racialized individuals and communities. The results have implications for ‘recognition’ and ‘belonging’ as benchmarks of democratic policing, and ‘the promise of inclusion’ associated with combatting hate crimes.