Police methods have changed dramatically around the world in recent years due to the advent of geo-positioning and improved computer-aided mapping techniques. As has happened throughout the history of policing, law enforcement officials have always tried to use new scientific research to their benefit. Since the object is the safety and comfort of local citizens, a major aspect of the mission for police departments is to always use the most up-to-date methods for the detection and apprehension of criminals. With the advent of computer-aided geographic information systems (GIS), police now have the ability to approach crime in an entirely new way.
According to Rich and Shively (2004) "geographical profiling was "born" in 1980 when a UK police investigator analyzed the locations of crime scenes of the Yorkshire Ripper and computed the "center of gravity" of the crime scenes…." This beginning has been debated by different people, but the fact is that GIS has been an aid to police for a number of years. One term that is used to explain the gamut of GIS methods is geographic profiling. Un attempting to give a comprehensive definition of the term Rich and Shively (2004) said that;
"Geographic profiling is a criminal investigative technique that attempts to provide information on the likely "base of operations" of offenders thought to be committing serial crimes…predictions are based on the locations of these crimes, other geographic information about the case and the suspect, and certain assumptions about the distance offenders will travel to commit crimes."
Since the data used to actually profile and locate offenders differs from system to system and department to department, it is simpler to use a less inclusive definition such as one that says that "geographic profiling…[is] a process used to attempt to discover the most probable area of residence of a serial offender" (Harries & LeBeau, 2007). Although this could also be said to be an error since the technique is now used to locate individuals who have committed individual crimes also, so cannot be said to be "serial offenders." Other definitions of various systems are useful, but since they apply to specific equipment and are not generally used in the paper, they will be given when a specific topic or system is introduced.
Different systems of GIS show significant advancements for police departments because they give information that was not easily obtainable prior to the advent of computers and GPS systems. However, there are issues, both in the legal realm and with types of software, that make further research and development a necessity. Determining how GIS was developed, what its relevant uses are, the differences and adequacies of the types used, and what problems they present are the focuses of this paper.
GIS was not a singular endeavor that arose because computers were invented. The process of improved police methods has been one that spans centuries most likely, but modern police methods can be traced back to at least 1881. According to Soullier's Stages of Technological Advancement in Policing there have been four distinct eras in the this process. They are:
Stage 1 (1881-1945): mobile patrol, radio communications, telephone communications
Stage 3 (1960-1979): 911 systems, centralized dispatch, civilian specialists, research and development organizations, computer age begins
Stage 4 (1980-present): telecommunications advances, mobile data communications, expert systems, imaging biometrics, GIS (Grant & Terry, 2005)
This list shows a logical progression through both electronic means of criminal detection and improved ways to conduct police work. Every time there is a new type of invention, many industries try to determine how it can be used to improve production, and the police department is no exception. The reason for this is simple. The mission of law enforcement is critical to the founding principles of the Declaration of Independence, namely that citizens shall have life, liberty and be able to pursue happiness. Law enforcement also has to grow with the times because criminal enterprises will also use new technologies to their advantage.
Computers mainly gave police the ability to coalesce different types of data quickly. Because there are many layers to crime that cannot be easily determined, even by a police officer walking a beat (as happened in many areas early in the country's history), the police needed a tool that could take a large number of variables and look for correlations that would point to hotspots. GIS systems use the factors known to affect crime which are (in part):
"Population density and degree of urbanization
Variations in composition of the population
Stability of the population
Modes of transportation and the highway system
Effective strength of law enforcement agencies" (Johnson, 2000).
All of these factors can be loaded into a program to narrow down a larger area of operation for an individual or group committing crimes. These can also be used to track areas in which crime is more frequent than other areas of a given region. For example, "A recent analysis of rapists in the UK…showed a median distance between offender residence and the crime site as 2.4 km; a comparable finding for U.S. data was 5.1 km with an average closest distance of 2.7 km" (Harries & LeBeau, 2007). This technique was one important factor used to determine the area within which a specific rapist operated. This data allows for the more rapid apprehension of criminals.
Of course, there is not just one type of GIS in use. Law enforcement agencies have different needs and there are various type styles used for the computer software that are more appropriate depending on the law enforcement unit using it. These types range from complicated mapping systems which give departments multiple layers of data to simple location devices that can be purchased quite cheaply by smaller departments. Alexander, Groff and Hibdon (1997) looked at how an "off-the-shelf" GIS product could be modified to enhance its usability based on local expert knowledge and dynamic data exchange or the "communication among the various software products" used. By using a simple GIS program and data collected from experts in the field (such as professionals from a rape or gang unit) even a large police force can turn a simple program into a means of compiling complex data and providing pinpoint information.
More complex computer methods were developed that assisted officers to an even greater degree. Craglia, Haining and Wiles (2000) analyzed different new computer-aided GIS methods and found that while they both had good applications, they both also had limitations. These two methods were standards used by different police departments, and newer generations of the same software are still used by police departments currently.
The coalescing of the programs is called problem-oriented policing which "puts the results of crime mapping, applied geography and theoretical analysis into practice in the field. In addition to help investigate individual crimes, this work has supported law enforcement in field and special operations, staffing and deployment decisions, and event planning" (Wilson & Smith, 2008). By using GIS techniques along with other information that can be gathered, police are better able to position their forces. This, again adds to the security of the public.
Uses for GIS
No matter what type of GIS system is used by law enforcement, they all have to modify the hardware and software to the purposes of the particular mission. One example is Border Patrol agents along the border with Mexico who use "real-time sensor feeds from the Intelligent Computer-Aided Detection System (ICAD), and monitor hits corresponding to potential illegal migrant entry into the country" (Grant & Terry, 2005). The officers are able to use existing data along with that gathered every shift to pinpoint areas of concern. Since the border with Mexico would be difficult to monitor in its entirety, and would require more officers than is economically feasible, this method allows agents to focus on certain targets while developing others. Their system also allows them to track covered culverts and other known tunnels into the United States through which illegals might enter the U.S.
A secondary benefit has also been realized from the use of mapping technology. One strategic use of GIS is that "by identifying discrepancies between predicted and observed crime rates, time series analysis can help determine if an outside influence, such as a crime prevention program, may be influencing criminal activity" (Canter, 1990). These trends would be almost impossible to spot without the aid of GIS technology that can take a large variety of data points and variables and coalesce it. Police use this mapping technology so that they can plan both strategically and tactically. Some GIS efforts allow police to gather data that is gathered over the long-term and can be used to notice trends within a community. These strategic efforts are geared toward "long-range problems and projections of long-term increases or decreases in crime" (Johnson, 2000). This could show police changes in hotspot…