The author(s) shown below used Federal funds provided by the U.S. Department of Justice and prepared the following final report: Document Title: The North Carolina Highway Traffic Study Author(s): William R. Smith ; Donald Tomaskovic-Devey ; Matthew T. Zingraff ; H. Marcinda Mason ; Patricia Y. Warren ; Cynthia Pfaff Wright Document No.: 204021 Date Received: January 2004 Award Number: 1999–MU–CX–0022 This report has not been published by the U.S. Department of Justice. To provide better customer service, NCJRS has made this Federally- funded grant final report available electronically in addition to traditional paper copies. Opinions or points of view expressed are those of the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of Justice. The North Carolina Highway Traffic Study Final Report to the National Institute of Justice U.S. Department of Justice By William R. Smith Donald Tomaskovic-Devey Matthew T. Zingraff H. Marcinda Mason Patricia Y. Warren Cynthia Pfaff Wright North Carolina State University Raleigh, North Carolina With Harvey McMurray C. Robert Fenlon North Carolina Central University Durham, North Carolina July 21, 2003 *This project was supported by Grant No.1999-MU-CX-0022 awarded by the National Institute of Justice, Office of Justice Programs, U.S. Department of Justice. Points of view in this document are those of the authors and are solely those of the authors and do not necessarily represent the official position or policies of the U.S. Department of Justice. Authors are listed with senior authors first, followed by junior authors (in alphabetical order). The authors would like to thank the five anonymous readers for their comments on an earlier draft of this report. Table of Contents Executive Summary......................................................1 Project Overview..................................................1 Official Records (Citations, Written Warnings, Searches, Stops) .............4 The Survey of North Carolina Drivers ................................12 Citizen Focus Groups ..............................................16 North Carolina State Highway Patrol Focus Groups ......................19 Chapter 1: “Driving While Black” and the North Carolina Highway Study .........23 The Work of the North Carolina State Highway Patrol....................25 The Importance of Process and Context ...............................35 Non-Bias Mechanisms that Could Produce Racial Disparity in Stops ........37 Deployment and Patrol Patterns .....................................40 References for Chapter One.........................................41 Chapter 2: The North Carolina State Highway Patrol Data Bases and Evidence of Racial Disparity at the Aggregate Level...............................42 Racial Disparity in Geographic Areas.................................42 Theories of Racial Disparity ........................................44 Methodological Issues .............................................50 The Importance of Context .........................................52 Citation Zones ...................................................53 Spatial Heterogeneity..............................................55 Proxy Measures of Citizen Behavior ..................................56 Command Policy and Procedures ....................................57 Aggregation Units of Analysis ......................................58 Stops, Citations and Written Warnings by Race. 61 Racial Disparity in Districts.........................................76 Proxy Measures of Citizen Driving Behavior ...........................76 Nationwide Personal Transportation Survey............................89 Spatial Heterogeneity..............................................93 Day and Night Rates .............................................104 What Are the Mechanisms that Generate Positives (and Negatives)? ........107 Citation Zones as a Causal Mechanism...............................111 Summary ......................................................114 References for Chapter Two .......................................117 Chapter 3: Racial Disparity at the Individual Trooper Level ...................119 Goals of Individual Trooper Analysis ................................119 Individual Level Characteristics ....................................120 Measuring the Context of the Officer’s Behavior ......................124 Identification of Troop Districts with Troopers as Statistical Outliers .......138 Conclusions....................................................144 References for Chapter Three ......................................152 i Chapter 4: Searches by the North Carolina State Highway Patrol................153 Race and Searches by the North Carolina State Highway Patrol ...........154 Troopers Accounts of Search Behavior ...............................155 Recorded Search Activity. 159 Probable Cause versus Consent Searches .............................170 Hit Rates ......................................................174 Individual Trooper Analyses .......................................177 Conclusion.....................................................178 Chapter 5: Citizen Survey Results: Racial Disparity in Self-Reported Stops........181 Introduction ....................................................181 Sample Characteristics............................................182 Racial Differences in Stops........................................183 Comparison of Driver Survey Estimates of Stops to Official Records. ......185 Racial Differences in Reported Stop Experience .......................187 Racial Differences in Reported Driving Behavior.......................191 Racial Differences in Demographic Background .......................195 Modeling Police Stops in a Multivariate Context .......................196 Discussion of Multivariate Results ..................................206 Racial Differences in Stop Experiences...............................206 Conclusions....................................................209 References for Chapter Five .......................................211 Chapter 6: Racial Differences in Trust in the Police ..........................212 Introduction . .212 Background ....................................................213 Racial Differences in Trust of the Police..............................215 Racial Differences in Personal and Network Stop Experiences ............215 Distrust of Government and Belief in Profiling .........................217 Modeling Distrust of the Police in a Multivariate Context ................219 Distrust of Government Officials Other than the Police..................221 Belief in Racial Profiling ..........................................222 Belief in Other Forms of Profiling ...................................224 General Distrust of the Police ......................................227 Distrust of the Local Police .......................................230 Distrust of the North Carolina State Highway Patrol ....................232 Conclusions....................................................233 References for Chapter Six ........................................237 Chapter 7: Discussion and Conclusions....................................238 Official Record Evidence of Disparity ...............................238 Criminal Interdiction Team........................................243 Indicators of Racial Disparity ......................................244 Self-Reported Traffic Violations and Stops............................245 Attitudes of the General Public .....................................246 Viewpoints of the North Carolina State Highway Patrol Troopers ..........247 Conclusion.....................................................249 ii Appendix A: Baseline Observational Study .................................251 Studying Driver Behavior .........................................251 Modified Carousel Method ........................................255 Baseline Data Collection..........................................258 Validating the Stopwatch Method...................................261 Correcting for Under-Estimation of Speed ............................265 References for Appendix A........................................273 Appendix B: North Carolina State Highway Patrol Focus Groups ...............274 North Carolina State Highway Patrol Focus Groups .....................276 Decision to Stop.................................................278 Enforcement Decision............................................283 Decision to Search...............................................284 Minorities and Traffic Stops .......................................285 Steps to Stop Racial Profiling ......................................288 Conclusion.....................................................290 Appendix C: Citation Charge versus Reason for Stop .........................292 Appendix D: Offense Codes for Citation Analysis............................303 Appendix E: Self-Reported Police Speeding Stops: Results from a North Carolina Record Check Survey ............................................333 Introduction ....................................................333 Background Literature ............................................335 Item Under- or Non- Reporting for Sensitive Questions ............335 Race and Item Under- or Non- Reporting for Sensitive Questions ....337 Record Check Surveys......................................338 Study Methods ..................................................340 Design of