Crime Mapping and theCrimestatProgramNed LevineNed Levine & Associates, Houston, TXCrimeStat is a spatial statistics program used in crime mapping. The program inputsincident or point locations and outputs statistics that can be displayed graphically in ageographic information systems (GIS) program. Among the routines are those forsummary spatial description, hot spot analysis, interpolation, space–time analysis, andjourney-to-crime modeling. Version 3.0 has a crime travel demand module foranalyzing travel patterns over a metropolitan area. The program and documentationare distributed by the National Institute of Justice.IntroductionIn this article, I will discuss the CrimeStat program and its potential uses for bothcrime mapping as well as other GIS applications.Crime mappingModern law enforcement has a strong technology component involving forensics,incident reconstruction, assailant profiling, database analysis, and a wide range ofspecialized analytical components including crime mapping. Crime mapping is animportant technical function that is part of modern police enforcement. Policeanalysts routinely map crime inciden ts in order to both detect general patterns ofcrime that can focus their enforcement and prevention efforts as well to identify andapprehend specific offenders who are committing crimes. Long known for thefamous pin map, invented by the London Metropolitan Police Department in the1820s, most large police departments in the United States and elsewhere routinelyuse geographic information systems (GIS) to map crime data as part of their strategicand tactical activities. The information gained from such analysis is used for avariety of applications from focusing deployment more specifically on hot spots totargeting crime prevention efforts on particular communities to tracking thebehavior of a serial offender for whom the police intend to apprehend and, even,to mapping motor vehicle crash locations, another police function.Correspondence: Ned Levine, Ned Levine & Associates, Houston, TXe-mail: [email protected]: January 1, 2004. Revised version accepted: March 10, 2005.Geographical Analysis 38 (2006) 41–56 r 2006 The Ohio State University 41Geographical Analysis ISSN 0016-7363The MAPS unitThe CrimeSt at program was developed by me under research grants from theMapping and Analysis Program (MAPS) of the National Institute of Justice (NIJ). Inthe United States, the NIJ is the research agency of the U.S. Department of Justice(USDOJ) and is part of the Office of Justice Programs. In 1996, NIJ created a crimemapping unit to develop and promote criminal justice analytical tools using GIStechnology. Originally called the Crime Mapping Research Center, the MAPSprogram has developed a collection of tools and applications on crime mapping(MAPS 2004). Among the tools developed or distributed by MAPS were a multi-jurisdictional spatial crime analysis package (RCAGIS), a mobile crime mappingtool for police cars (the Community Policing Beat Book), an ArcView crime analysisextension, a client–server version of a regional crime analysis pro gram (RCAP-SDE),a school crime incident tool for documenting and mapping crimes occurring inschools (School COP), along with CrimeStat. The MAPS unit has also run an annualcrime mapping conference, created formal and self-training courses on crimemapping, funded many research studies on crime mapping (e.g., LeBeau 1997;LaVigne and Wartell 1998, 2000; Harries 1999; Jefferis 1999; Rich 2001; Wartelland McEwen 2001; Stoe et al. 2003), and are developing a regional spatial datarepository for crime and terrorist incidents occurr ing in the United States. Moreinformation about MAPS can be found on their Web site.1TheCrimeStatprogramCrimeStat is a stand-alone Windows spatial statistics program for the analysis ofcrime incident locations that can interface with most desktop GIS programs. Thepurpose is to provide supplemental statistical tools to aid law enforcement agenciesand criminal justice researchers in their crime mapping efforts. The NIJ is the soledistributor of CrimeStat and makes it available for free to analysts, researchers,educators, and students.2The program is distributed along with a manual that des-cribes each of the statistics and gives examples of their use.The program is written in C11 and is multithreading. It was designed withlarge databases in mind as most metropolitan police departments work with largefiles. It will also take advantage of multiple processors in a computer which, for alarge data set, will considerably cut down on calculation time. The program alsoincludes Dynamic Data Exchange code to allow another program to call upCrimeStat and pass the data set name and variable parameters to it. Such a usewas developed by the Criminal Division of the USDOJ in developing their RegionalCrime Analysis GIS (RCAGIS).3Several jurisdict ions in the Baltimore metropolitanarea use RCAGIS to link crime databases to a common interface and a set ofanalytical tools, including CrimeStat.CrimeStat is being used by many police departments around the country aswell as by criminal justice and other researchers. Four versions have been released.The first was released in November 1999 and an update version was released inGeographical Analysis42August 2000. Version 2.0 was released in August 2000. The latest version,CrimeStat III, was released in March 2005. From what we can tell, it has beenused in many courses and has been a widely used research tool.4The program hasalso been used by researchers from other fields than criminal justice includinggeography, epidemiology, forestry science, botany, and geology.Data input and outputThe program inputs incident locations (e.g., robbery locations, motor vehicle crashsites, residence locations of persons with a particular disease) in ‘‘dbf,’’ ‘‘shp,’’‘‘dat,’’ or ASCII formats, as well as programs that follow the ODBC standard. It canuse spherical or proje cted coordinates. It can also treat zones as pseudo-points (orpoints with intensities). Although there is a primary file that must be input, theprogram can allow secondary and other files to be use d for comparison orspecialized purposes . The user can also define a reference grid by the coordinatesof the ‘‘corners’’ and the program will create it for specialized uses.Once the data are input, the program calculates various spatial statistics. Thesevary from very simple descriptions to complicated spatial