Geographic Profiling

Serial Crime Investigative Difficulties

Serial and “stranger” crimes are difficult to solve and pose significant challenges for law enforcement agencies because the investigations cannot work outward from the victim. Rather, the process must work inward by considering large populations of suspects (e.g., all registered sex offenders, known bank robbers, recent parolees, owners of certain vehicles types, public tips, etc.). This typically leads to information overload and resource problems. In efforts to address this situation, police and researchers have turned to the behavioral sciences.

Behavioral Science

Geographic profiling falls into the behavioral science repertoire of criminal investigative support techniques. Linkage analysis and criminal investigative analysis are the other main components of this toolkit. Linkage analysis attempts to connect related crimes through an examination of the offender's modus operandi and signature. Criminal investigative analysis (CIA) includes psychological profiling and similar techniques. Psychological profiling infers an offender's personality and behavioral characteristics from his or her crime scene behavior. Criminal or offender profiling can be more generally defined as the inference of offender characteristics from crime scene characteristics. Geographic profiling, because it infers an offender's residence area from the locations of his or her crime sites, can be considered part of criminal profiling.

Crime Pattern Theory

As haphazard as crime may sometimes appear, there is a rationality influencing the geography of its occurrence and a semblance of structure underlying its spatial distribution. Using an environmental criminology perspective, Brantingham and Brantingham present a series of propositions that provide insight to the processes underlying the geometry of crime. Their model of offense site selection, called crime pattern theory, suggests that criminal acts are most likely to occur in areas where the “awareness space” of the offender intersects with perceived suitable targets (i.e., desirable targets with an acceptable risk level attached to them).

An individual's “activity space” is constructed from his or her residence, workplace, recreational sites, and the travel routes between these locations. A criminal's activity space, in conjunction with his or her “hunting” style, determines search patterns and hunting grounds. Crime locations are therefore a function of an offender's residence and activity space.

Routine Activity Theory

Routine activity theory asserts that for a contact predatory crime to occur, there must be an intersection in time and space between a motivated offender, a suitable target, and the absence of capable guardianship. The routine activity approach can be useful for understanding the circumstances surrounding a crime and the specific actions of the offender and the victim preceding their encounter.

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