Crime, Geography of

The geography of crime is the study of the spatial arrangement of criminals and crime. Geographic research on the location of criminals began in Western Europe during the early 1800s. Termed the cartographic school, researchers mapped the homes of criminals and related these maps to the socioeconomic environments of the country. At the turn of the 20th century, the geography of crime became more focused on urban areas when the urban ecologists at the University of Chicago related the home addresses of delinquents with characteristics of urban neighborhoods thought to spawn delinquency. The spatial pattern that they discovered is termed the urban crime gradient, which is the tendency for the number of criminals living in a neighborhood to decline with distance from the center of the city.

In contemporary times, the focus of geography of crime has shifted to the location of crime rather than the location of criminals. Because criminals must leave their homes to commit most crimes, analysts have focused on the three geographic concepts that describe this movement to a crime site: distance, direction, and reference point. These are three concepts that are used to locate anything in space.

Distance research has discovered that crime trips tend to follow a definite distance decay function. Criminals tend not to travel any farther than necessary to locate a crime site. However, if the crime is confrontive, they tend to avoid a buffer zone around the home. Therefore, the probability of a confrontive crime, such as rape or robbery, tends to increase with distance from the home until the edge of the buffer zone is reached and then decreases rapidly, following the principle of expending the least effort necessary to identify an opportunity for crime while avoiding recognition. Recently, these principles have been applied in geographic profiling where analysts attempt to predict the likely location of the home of a serial offender from the spatial arrangement of the offenses committed. Again, the assumption is that the offender lives in close proximity to the crimes committed.

Directional analysis focuses on the nature of places that have a lot of criminal activity surrounding them. These places are of two types: crime generators and criminal attractors. Crime generators are places such as high schools that cluster many people, some of whom have criminal tendencies, in one place on a daily basis. Criminal attractors are places to which criminals travel to identify a criminal opportunity. Examples include ATM machines for robbers, parking lots for auto thieves, and beaches for rapists. Because criminals will come from varying distances, the focus is on the directional bias toward one of these facilities. Directional bias is generally measured from the home of the criminal. Rather than using the four cardinal directions, bias is measured with respect to some anchor point such as the center of the city (toward or away from it in degrees on a protractor). Other anchor points that have been used in directional research of the spatial movement of criminals are workplaces, recreation areas, and illegal drug markets. Again, the spatial movement of the criminal is measured toward or away from the anchor point in degrees.

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