Crime Scene Investigation Mapping: Understanding Hot Spots

AUG. 05 U.S. Department of Justice Office of Justice Programs National Institute of Justice Special REPORT Mapping Crime: Understanding Hot Spots www.ojp.usdoj.gov/nij U.S. Department of Justice Office of Justice Programs 810 Seventh Street N.W. Washington, DC 20531 Alberto R. Gonzales Attorney General Regina B. Schofield Assistant Attorney General Sarah V. Hart Director, National Institute of Justice This and other publications and products of the National Institute of Justice can be found at: National Institute of Justice www.ojp.usdoj.gov/nij Office of Justice Programs Partnerships for Safer Communities www.ojp.usdoj.gov AUG. 05 Mapping Crime: Understanding Hot Spots John E. Eck, Spencer Chainey, James G. Cameron, Michael Leitner, and Ronald E. Wilson NCJ 209393 Sarah V. Hart Director This document is not intended to create, does not create, and may not be relied upon to create any rights, substantive or procedural, enforceable by law by any party in any matter civil or criminal. Findings and conclusions of the research reported here are those of the authors and do not necessarily reflect the official position or policies of the U.S. Department of Justice. The products, manufacturers, and organizations discussed in this document are presented for informational purposes only and do not constitute product approval or endorsement by the U.S. Department of Justice. The National Institute of Justice is a component of the Office of Justice Programs, which also includes the Bureau of Justice Assistance, the Bureau of Justice Statistics, the Office of Juvenile Justice and Delinquency Prevention, and the Office for Victims of Crime. Cover Credits (From left to right) Map by Jeff Stith and the Wilson, North Carolina, Police Department Map by Wilpen Gore, Heinz School of Public Policy and Management, Carnegie Mellon University, Pittsburgh, Pennsylvania Background map by Jeff Stith and the Wilson, North Carolina, Police Department About This Report Much of crime mapping is devoted to detecting high-crime-density areas known as hot spots. Hot spot analysis helps police identify high-crime areas, types of crime being committed, and the best way to respond. What did the researchers find? ■ Identifying hot spots requires multiple techniques; no single method is suffi­ cient to analyze all types of crime. This report discusses hot spot analysis techniques and software and identifies when to use each one. The visual display of a crime pattern on a map should be consistent with the type of hot spot and possible police action. For example, when hot spots are at specific addresses, a dot map is more appropriate than an area map, which would be too imprecise. ■ Current mapping technologies have sig­ nificantly improved the ability of crime analysts and researchers to understand crime patterns and victimization. ■ Crime hot spot maps can most effective­ ly guide police action when production of the maps is guided by crime theories (place, victim, street, or neighborhood). In this report, chapters progress in sophis­ tication. Chapter 1 is for novices to crime mapping. Chapter 2 is more advanced, and chapter 3 is for highly experienced analysts. The report can be used as a com­ panion to another crime mapping report published by the National Institute of Justice in 1999, Crime Mapping: Principle and Practice, by Keith Harries. Who should read this study? Crime analysts and researchers in police departments. iii Cont