Synthesis 2000 (continued)
Chapter 5: Synthesis and Applications

GIS mapping. The predominant applications of GIS have involved the representation of point, area (polygon), and line data for reasons that have been outlined previously. However, as databases become more integrated and newer technologies like global positioning systems (GPS) become more commonplace, we might expect the "traditional trio" of point, area, and line to be supplemented by an ever-richer array of raster data in the form of digital orthophotography and other photographic images. The wide availability of orthophotography (often commissioned by local governments) combined with the advent of inexpensive digital cameras and (still somewhat expensive) digital video recorders presages the fuller integration of all georeferenced "visual" data. Most likely, traditional point, area, and line maps will begin to be embedded with useful raster elements, so that the user will have the choice of seeing a map or bringing up an orthophoto and/or a ground-level photo of the location of interest. (See chapter 6 for more on orthophotography applications.)

Other nontraditional applications include, for example, public safety events, in which police, fire, and other agencies are brought together in a common effort to alleviate a natural disaster. A map constructed for this purpose (figure 5.5) details data that provided general locations of police and fire units during a catastrophic flood in Dallas, Texas.

Figure 5.5

Ever-decreasing costs. Decreasing costs have brought mapping technology within the reach of agencies that would not otherwise have been able to acquire it. In the early days of the Information Age, equipment and software often cost more than the operator; now that situation is reversed. But the impact of less expensive technology goes deeper. Not only can agencies put computers on their workers' desks, but those computers are increasingly powerful and thus provide additional opportunities that slower or memory- challenged devices could not have accommodated. For example, very large raster files, unmanageable until recently, no longer pose as much of an access problem as they once did.

Crossjurisdiction alliances. The belief that "all politics are local" has inhibited collaboration between police agencies. The mantra has been that local problems should be solved locally, although the use of State or Federal dollars was acceptable provided not too many strings were attached. Unfortunately, offenders have not subscribed to the notion that they should recognize city, county, and State lines.

The following inconsistencies among law enforcement agencies have acted to make political boundaries "law enforcement opaque" rather than transparent or invisible, as criminals perceive them:

  • Different radio frequencies.

  • Different protocols for hot pursuits.

  • Agencies competing with one another in hot pursuits and investigations.

  • Lack of information sharing and coordination between administrative units and/or agencies (referred to as "linkage blindness" by Rossmo, 1995).

Mapping has helped break down such barriers due to its power to provide visual evidence that criminal groups or individuals move across boundaries at will, sometimes intelligently exploiting the lack of communication between agencies. The increased interlinking of databases needs to be coupled with jurisdictional interlinking so that the official view of crime more closely corresponds to regional reality. Politically bounded areas, whether cities, counties, or States, rarely conform to social areas. Until policing areas more closely conform to or recognize social areas, crime analysis and prevention will be stymied to some degree. Crime mapping has tended to focus on technical issues, but the bigger picture—Are we mapping and analyzing the most appropriate areas?—also deserves attention. Crime can be a regional phenomenon. Regional problems call for regional solutions.

Theory and practice. Crime mapping is typically based on experience and observation, with a weak or nonexistent theoretical foundation. Empirical and theoretical perspectives battle each other in the here-and-now world of law enforcement. When tangible flesh-and-blood problems need to be taken care of immediately, theory is at best abstract, at worst completely irrelevant. But theory does have a place as a conceptual backdrop—a reference base that can provide consistency to our analyses and tactical responses. Eck (1997) pointed out that as the theoretical content of maps increases, it becomes easier to make sense of the data (see also Eck and Weisburd, 1995). In other words, if a map shows only crime locations, indepth explanation of pattern is next to impossible. But if other elements of context are included, such as the socioeconomic environment or locations of drug markets or of abandoned housing, (any elements that theory would lead us to expect to be linked to the crime pattern in some way), then understanding is likely to be enriched. For example, a CFS map, such as in figure 5.6, may be substantially more meaningful when the CFS are displayed along with housing code violations. "Negative" information showing where the anticipated link between conditions fails to apply may be just as useful as "positive" information showing where the link does apply.

Figure 5.6

Data sharing. Local and State governments are finding that data gathered by one agency might be valuable to others. This is not surprising, given the baffling complexity of social problems, including crime. Social scientists have long recognized that social systems are in some ways like natural ecosystems: change something and everything else changes to some degree. Land use patterns and changes, demographics, transportation system configurations, the weather, and the strength of social controls embedded in the culture—these and many more factors influence patterns of crime. It makes sense to give crime analysts access to the rich variety of data they need to help them answer the widely varied questions that come their way.

Gradually, and inconsistently in terms of geography, "community" approaches to problem solving dictating collaboration and data sharing among agencies are gaining popularity.

Context. A relatively recent trend in crime analysis emerging from the community policing movement has been the increasing tendency to see crime "in context" rather than as a self-contained phenomenon with self-contained solutions. A broad view is needed, one that incorporates understanding of social background and crime patterns. Complete preoccupation with patterns and their immediate causes is a kind of professional shortsightedness that may miss fundamental causal processes (see Sherman et al., 1998, for more on the broad view of crime prevention). Crime analysis that ignores this wider perspective, or backdrop, runs the risk of ignoring important connections to community-based processes. This again reinforces the importance of making a variety of data available to police officers and crime analysts alike.

Privacy issues. Privacy questions are touched on elsewhere in this guide, but they also deserve a mention in any discussion of synthesis. In marked contrast to the cultures of many other developed nations, U.S. culture is quite resistant to government intrusion, even when that intrusion seems to be well intentioned and in the apparent best interest of the majority. Along with this goes a degree of mistrust of law enforcement, a posture reinforced by high-profile events such as the Rodney King affair in Los Angeles, the Abner Louima incident in New York City, and the Branch Davidian standoff in Waco, Texas. Fears of privacy violations by law enforcement are only part of broader societal concerns about privacy and the inherent mistrust of authority.

These concerns were exemplified by the controversy surrounding the activities of Image Data, LLC, a small New Hampshire company that in 1999 attempted to build a national database of driver's license photographs, ostensibly to combat check and credit card fraud. After Colorado, Florida, and South Carolina had contracted to supply their license pictures, it was discovered that the photo file was also to be used to combat immigration abuses, terrorism, and other identity-related crimes. It then became known that Congress had contributed $1.5 million to the effort and that the U.S. Secret Service had lent a hand, elevating the controversy to new heights and provoking initiatives from the three States to cancel their contracts (O'Harrow and Leyden, 1999; for a more detailed analysis, see Paisner, 1999).

This type of data gathering is one of many ways in which data relating to individual persons, families, or households can be accessed and compiled. The use of branded credit cards and discount cards in stores enables retailers and marketing companies to track every purchase and develop spending profiles of consumers. When information from this kind of database is added to information that can be accessed via directories, maps, remotely sensed imagery (e.g., aerial photos, satellite images), and various and progressively more integrated public records, anxiety about privacy violations, real or imagined, understandably escalates.

Crime mapping can be seen as a piece of this privacy issue, although whether one elects to put a sinister spin on the technology is obviously a personal decision. As yet, no conspicuous backlash against crime mapping has occurred (with the possible exception of Megan's Law), but whether this type of public reaction will occur in the future is an open question.

Public access. Conflict over privacy and access is inevitable. For every person or group that lobbies to restrict the dissemination of crime-related information, another lobbies to gain more access. Surprisingly, access to crime data is still denied to researchers on occasion. Denying bona fide researchers access for projects that are ostensibly in the public interest clouds confidence in the data-gathering process, since it inevitably raises questions about the reasons for denial of access.2 As noted elsewhere, it would seem that most crime data eventually are released to the public through court proceedings and so on. What could be damaging and should obviously be avoided is making unfounded data accessible to the public (e.g., on the Web), since it carries the accompanying risk of defaming the innocent.

A controversial development in recent years has been the tendency of some States to put lists of sex offenders on the Web, Virginia being the 10th State to do so in late 1998. The names of more than 4,600 violent sex offenders were made available to the public, with the effect of "giving parents a new tool to protect their children but also renewing fears about the erosion of privacy in the Information Age" (Timberg, 1998).

The names, ages, home addresses, conviction records, and photographs of Virginia offenders are listed at, a Web site that recorded more than 650,000 visitors in less than 2 months after it was launched. Predictably, State officials were enthusiastic about the site, while civil libertarians suggested that it amounted to double punishment, with the additional possibility that offenders' children would be put in jeopardy. Other potential risks include the possibility of disseminating false information (from computer hackers or errors in the original files) and vigilantism. To date, registries have not been evaluated adequately, but they are greeted with enthusiasm by parents anxious to protect their children.

Many law enforcement agencies have developed Web sites displaying crime maps (see appendix and various examples throughout this guide). Some elect to show crimes in the form of point data, while others use choropleth or shade maps. Sharp differences of opinion have been voiced over the appropriateness of such maps. Opponents fear negative consequences for high-crime communities; under the worst case scenario, crime maps may provoke full-scale flight from neighborhoods. Proponents tend to be community-policing advocates who see full disclosure of information as a tool in crime prevention. They see Web-based maps as community resources providing citizens with unbiased, ready access to crime patterns. If citizens can see where crime is, the argument goes, they will be better collaborators in crime prevention.

Chapter 5: Synthesis and Applications
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Mapping Crime: Principle and Practice, by Keith Harries, Ph.D., December 1999