Traffic Stops Research Articles

Traffic Stops, Stopping Traffic: Race and Climate Change in the Age of Automobility

Traffic Stops, Stopping Traffic: Race and Climate Change in the Age of Automobility

How do police use race in traffic stops and searches? Tests based on observability of race

When a police officer decides whether to initiate a traffic stop, the driver's race is less likely to be known during darkness, but always observed after the stop takes place. If officers use information optimally, this flow of information about race leads to specific empirical predictions, which are tested using data on traffic stops in Minneapolis. The prediction about stops is supported, but those concerning searches are not. This pattern of results implies that police choices were inconsistent, which is evidence against both statistical discrimination and optimizing with a taste for discrimination. The results may reflect cognitive biases present in the time-sensitive decision to initiate a stop.

Policing the Police: Reexamining the Constitutional Implications of Traffic Stops

Policing the Police: Reexamining the Constitutional Implications of Traffic Stops

Analysis of the Effect of the Lane-Drops on the Traffic near Bus Stops using Bus GPS Data

Abstract: In congested cities where the commuting time doubles during peak hours, it is crucial to identify every network problem. While it is costly to implement classic sensor technologies all around the network, the trajectory data of GPS equipped bus fleet can be used for analyzing the traffic. In this study, we suggest a brief methodology to implement bus trajectory data analysis to investigate the congestion on the selected network under peak and off-peak hours in relation with the lane-drops and the speeds of the buses below a threshold value of 5.9 km/hr. The bottlenecks in the study network are identified along the bus route considering the locations and the time of the day.

The Incidence of Money Collected by the Ghana Police from Drivers during Routine Traffic Stops and Ad Hoc Road Blocks

It is often said the Ghana Police force is corrupt without collaborating evidence. There is very little attempt to differentiate specific branches of the force from each other. There are those, whose Standard Operating Procedures involves road traffic duties, and those whose SOPs do not expose them to driver inducement to bribes. We conducted baseline, cross-sectional nation-wide study to determine the incidence of the police collecting money from drivers to support or rebut the perception and the reality of police corruption with specific attention to only traffic related corrupt practices. This study therefore relates only to the narrow issue of traffic-stop-driver-Police-bribery-and-corruption. The High Police such as the Bureau of National Investigation and the Economic and Organized Crime Office, were excluded as not forming an intrinsic part of the police force engaged in mundane road traffic police functions. We found evidence that supported the research question: That the Ghana Police engages in active intimidation of drivers, extract and demand for money from drivers of all classifications for cause and without cause. The traffic Police conduct these activities in the most blatant and public manner. These activities have contributed to the lessening of respect for the profession, the rule of law, and the general public belief that justice in Ghana correlates to size of expenditure to bribe law enforcement operatives. Road traffic corruption undermines road safety programs, national efforts to reduce money laundering or cross-border movement of terrorists and narcotics drug smuggling cells. This may have a linkage to the rising road traffic fatalities in significant ways. National action to arrest the diminishing respect for the Police is also needed.

Evaluating the relative impact of positive and negative encounters with police: a randomized experiment

Examines the influence of positive, negative, and neutral police behavior during traffic stops on citizen perceptions of police. Participants were randomly assigned to view a video clip of a simulated traffic stop in which the officer communicates with the driver in a positive (procedurally just), negative (procedurally unjust), or neutral manner. After viewing the video, participants completed a survey about their perceptions of police, including their level of trust in police, obligation to obey police orders, and willingness to cooperate with police. Observing positive interactions with police enhanced people’s self-reported willingness to cooperate with police, obligation to obey police and the law, and trust and confidence in police, whereas observing negative interactions undermined these outcomes. The effects of these interactions were much stronger for encounter-specific outcomes than for more general outcomes. The results from this randomized experiment confirm that procedural justice can enhance people’s prosocial attitudes toward police, whereas procedural injustice can undermine these attitudes. While positive (procedurally just) interactions tend to have weaker effects than negative (procedurally unjust) interactions, this study finds little support for the notion that only negative experiences shape people’s views about the police.

Interdiction for the protection of children: Preventing sexual exploitation one traffic stop at a time

Abstract This paper describes an innovative policing approach for identifying potential exploitation of children during roadside traffic stops and other interactions with citizens. The goal of the Interdiction for the Protection of Children program (IPC) is to train law enforcement officers to identify: (a) individuals who pose a high risk to children; (b) children who are being trafficked, exploited, or abused by one or more adults; and c) children who are at risk for various forms of exploitation (e.g., runaways, abductees). The training component first provides law enforcement officers with a conceptual framework for understanding child sexual exploitation. Next, instructors train participants to identify overt as well as subtle indicators that an individual with whom they are interacting may be a child victim, a child at risk for victimization, or a perpetrator of a sexual crime. Trainers emphasize the importance of working within multidisciplinary child protection systems to ensure the well-being and safety of each child. Upon the completion of training, officers utilize their skills on the street to better detect and intervene in matters involving child sexual exploitation, and intelligence analysts and researchers collect data from field personnel to improve program effectiveness. In the current document we describe the program's methodology and application, including results of two major operations. We also discuss implications and provide suggestions for future directions.

Testing the Effects of Procedural Justice and Overaccommodation in Traffic Stops

Research shows that perceptions of procedural justice influence people’s trust, confidence, and obligation to obey law and legal authorities as well as their willingness to cooperate with and support legal authorities. Interpersonal interaction styles that are central to procedural justice theory also play a key role in communication accommodation theory (CAT). Based on video clips depicting a police traffic stop, we use a randomized experiment to test the effects of procedural justice and overaccommodation on trust in police, willingness to cooperate with police, and obligation to obey police and the law. The results demonstrate that procedural justice has more powerful effects than overaccommodation on reported trust and confidence in the officer, as well as respondents’ obligation to obey and willingness to cooperate with the officer. Moreover, although procedural justice generated strong effects on encounter-specific attitudes, it did not exert any effect on more general attitudes toward police.

The Impact of Procedurally-Just Policing on Citizen Perceptions of Police During Traffic Stops: The Adana Randomized Controlled Trial

Objectives The process-based model of police legitimacy suggests, when police are perceived to make fair decisions and treat people with respect, they will be viewed as legitimate authorities. A randomized controlled trial was used to test the impact of a procedural justice policing intervention, relative to routine police behavior, during traffic stops for excessive speeding in Adana, Turkey.

Intersectional Race Effects on Citizen-Reported Traffic Ticket Decisions by Police in 1999 and 2008

Do the intersections between officer race and driver race/ethnicity influence the frequency in citizens’ reports of receiving a traffic ticket during a routine traffic stop in 1999 and 2008? To fully grasp the importance of traffic ticket outcomes, we must first understand how extralegal factors, particularly the intersections between officer race–driver race/ethnicity and the number of vehicle occupants, impact these outcomes. Thus, the current study utilizes the 1999 and 2008 Police–Public Contact Survey to assess the relationship between extralegal factors and traffic ticket receipt during routine traffic stops. Findings illustrate that according to citizens’ reports, extralegal factors, including the intersections between officer race–driver race/ethnicity and the number of vehicle occupants, differentially impact traffic ticket receipt in both the years.

Frisky business: race, gender and police activity during traffic stops

Since the United States Supreme Court laid the foundation for “stop-and-frisk” activity by police departments, a substantial amount of research has explored the behavior of police departments, particularly with respect to race. But previous work rarely focuses on the individual’s probability of receiving a frisk. By exploiting a traffic stop-level dataset from the Pittsburgh Police Department, the marginal effects of assorted driver characteristics are estimated. While the broad characterization of African-American drivers being more likely to receive a frisk remains accurate, several related factors are identified that create a more nuanced picture of a driver’s probability of being frisked. The interaction of the gender of the driver, the time of day of the traffic stop, and the existence of passengers in the stopped vehicle with the race of the driver all impact the probability of receiving a frisk.

An Evaluation of an Observational Benchmark Used in Assessing Disproportionality in Police Traffic Stops: A Research Note

Researchers use observational benchmarks to assess racial disproportionality in police traffic stops. To date, there has been a deficiency of empirical research evaluating the effectiveness of observational benchmarks across time-of-day and in comparison to census data. This article is a research note that reports the findings from analyses evaluating relative accuracy of daytime roadside observations in comparison with nighttime observations. Results indicate that daytime observations are more valid than nighttime observations and that daytime benchmarks if formed from small localized geographical areas are similar to residential census population data. The implications of these findings are discussed.

Discovering Arrest Warrants During Illegal Traffic Stops: The Lower Courtss Wrong Turn in the Exclusionary Rule Attenuation Analysis

Suppose that a police officer illegally stops a vehicle, discovers that the driver has an outstanding arrest warrant, and takes him into custody. Should evidence then seized in a search incident to the arrest be admissible under the theory that the discovery of an outstanding arrest warrant attenuates the taint of the illegal traffic stop? This question has been the subject of heated conflict in both federal and state courts. Courts are divided, and even those that agree have failed to apply a consistent analysis, leading to unpredictable results. This article is the first to provide an in-depth analysis of this issue and to propose how the courts should apply the exclusionary rule. It advocates a strict application of the Brown v. Illinois attenuation factors, which will typically lead to the suppression of the fruit of an illegal traffic stops despite the discovery of an arrest warrant. This article also addresses the lower courts' misapplication of Brown and how this failure leads to grave public policy concerns and threatens to reduce the Fourth Amendment to a mere form of words.

Beginning to End Racial Profiling: Definitive Solutions to an Elusive Problem

Many Americans have had interactions with police officers and other law enforcement agents, and the majority of these police-citizen encounters occur in the context of traffic stops. Although mildly inconvenient, traffic stops are necessary not only for enforcing traffic rules and deterring traffic violations, but they are generally beneficial for broader public safety concerns. For many people, traffic stops are simply part of life. For many racial minorities, however, especially African-American and Latino men, even a routine traffic stop takes on an entirely different meaning. Historically, the relationship between racial minorities and police has been strained, and many members of racial minority groups believe that law enforcement officers unfairly target them because of their race or ethnicity. It is widely known that many Americans, especially minorities, believe that police officers use race as a proxy for criminal involvement. There is strong evidence that racial minorities believe law enforcement officers engage in racial profiling. African-Americans have long argued that police officers scrutinize their behavior more closely, and many report that they are fearful of arrest even if they have done nothing illegal. The majority of African-Americans believe that racial profiling is wrong, yet is pervasive within their communities. Unfortunately, there is a growing body of evidence that suggests that the perception that police unjustly target minorities is not merely an unsubstantiated feeling, but an uncomfortable reality. While all forms of police misconduct or corruption are disturbing, racial profiling occupies a unique place among such harmful practices because it presents several unique issues that make it difficult to address through standard police accountability measures. Society entrusts law enforcement officers with a wide-breadth of discretion in order to perform their everyday duties. While the fast-paced nature of law enforcement necessitates discretion, if left unchecked, broad grants of discretion can lead police officers to abuse their position and engage in misconduct ranging from falsifying evidence, participating in violent excessive uses of force, and engaging in racial profiling. Remedying an elusive practice such as racial profiling remains a challenging issue for the judiciary and reformers must rely on other avenues for a solution. This Article argues that while courts may be reluctant to provide judicial remedies, police departments themselves should not ignore the perceptions and should take measures to reduce any possible profiling and increase partnerships with communities.

Optimising the length of random breath tests: Results from the Queensland Community Engagement Trial

Research suggests that the length and quality of police–citizen encounters affect policing outcomes. The Koper Curve, for example, shows that the optimal length for police presence in hot spots is between 14 and 15 minutes, with diminishing returns observed thereafter. Our study, using data from the Queensland Community Engagement Trial (QCET), examines the impact of encounter length on citizen perceptions of police performance. QCET involved a randomised field trial, where 60 random breath test (RBT) traffic stop operations were randomly allocated to an experimental condition involving a procedurally just encounter or a business-as-usual control condition. Our results show that the optimal length of time for procedurally just encounters during RBT traffic stops is just less than 2 minutes. We show, therefore, that it is important to encourage and facilitate positive police–citizen encounters during RBT at traffic stops, while ensuring that the length of these interactions does not pass a point of diminishing returns.

Race, poverty, and the traffic ticket cycle

Purpose – Through systematic observation of police decision-making behavior, the aim of this paper is to investigate what factors differentiate between citizens who receive a warning vs a ticket from police and whether the influence of those factors varies by race. The paper also explores the context of those decisions for both blacks and whites to further the understanding of the underlying mechanisms of any observed differences in the likelihood of receiving a ticket vs a warning. Design/methodology/approach – Data were collected during police ridealongs conducted in a sample of cities within Cuyahoga County, Ohio. A total of 140 ridealongs were completed, yielding a total of 312 vehicle or citizen stops. Findings – The paper finds that black citizens are more likely to receive a ticket than white citizens. However, the paper also finds important differences in the situational context of traffic stops for blacks and whites and uncover evidence of a cycle of traffic tickets and license suspensions among some black drivers. Research limitations/implications – The study demonstrates the importance of examining the underlying situational context in analyses of decision making in traffic stops. The main limitation of the analyses is that the data were limited to one county in the state of Ohio. Practical implications – The data suggests that one of the causes of the racial disparities in tickets vs warnings involves a cycle of tickets and license suspensions that occurs among some black drivers. These drivers appear to become caught up in a cycle where a compilation of prior tickets from traffic infractions, driving without insurance, or defaulting on child support payments leads to high numbers of points and subsequent license suspensions. The paper discusses some practical implications for addressing this pattern, including specific programs that could be adopted by municipalities that seek to break the cycle of repeated violation of driver's license laws. Originality/value – Beyond identifying the impact of citizen race on the likelihood of receiving a warning vs a ticket during a traffic stop, this study contributes to the existing literature by exploring the situational context of these decisions, and identifying the ways in which variations in situational contexts help explain racial differences in outcomes in traffic stops. The identification of a traffic ticket cycle among some black drivers appears to be an original finding.

The Impact of Population Selection on Examinations of Discretionary Searches in Traffic Stops

The current study explores whether inconsistent findings in published research regarding the relationship between driver race and discretionary searches can be explained by variation in methodology. A review of published research reveals a consistent pattern between the populations of drivers included in analyses—all drivers or searched drivers—and the relationship between driver race and discretionary searches. This methodological explanation is tested using data from a large municipal agency and confirms that variation in the association between driver race and discretionary searches is based on the population used in analyses. The results and implications are further discussed.

Resolving the Tolentino Question: Why Courts Should Suppress Police Observations and Other 'Identity-Related' Evidence Flowing from Illegal Traffic Stops

Some courts hold that a person’s identity evidence obtained through a Fourth Amendment violation, such as in an illegal traffic stop, is not suppressible. But the Court has never made such a broad exception. The Court has only said that a defendant cannot avoid a court’s jurisdiction by claiming their identity was illegally obtained. Specifically, the Court has repeatedly held that intangible evidence is suppressible when obtained by way of an illegal search or seizure. Accordingly, this Comment argues that a person’s “identity-related” evidence, including police officer observations, should be suppressed when obtained by way of a Fourth Amendment violation.

Traffic Stops and the New Exclusionary Rule Regime: Why Harris, Hudson, and Herring Mandate that the Discovery of an Outstanding Arrest Warrant Should Attenuate the Taint of an Illegal Traffic Stop except in the Case of a Flagrant Fourth Amendment Violation

Traffic Stops and the New Exclusionary Rule Regime: Why Harris, Hudson, and Herring Mandate that the Discovery of an Outstanding Arrest Warrant Should Attenuate the Taint of an Illegal Traffic Stop except in the Case of a Flagrant Fourth Amendment Violation

Searches and Traffic Stops: Racial Profiling and Capriciousness

The purpose of the present study is to examine traffic stop data—in particular data on searches—to better understand racial profiling. We use a measure of capriciousness to understand whether the decision to search occurs at random. Using data from more than 40,000 traffic stops from Louisville, Kentucky, the present study finds that race is one of many factors that are used in the determination of a search. For the overall, White, and Black samples, we find that the decision to search occurs at random, suggesting that racial profiling is not occurring in these data.