Crime statistics can paint a picture of crime in America; unfortunately, the picture is not completely reliable. It is important for all data users to become as well educated as possible about how to understand and quantify the nature and extent of crime in the United States and in any of the more than 17,000 jurisdictions represented by law enforcement contributors to the Uniform Crime Reporting (UCR) Program. Valid assessments are possible only with careful study and analysis of the various unique conditions affecting each local law enforcement jurisdiction. Until data users examine all the variables that affect crime in a town, city, county, state, region, or other jurisdiction, they can make no meaningful comparisons. Some factors that are known to affect the volume and type of crime occurring from place to place are:
- Population density and degree of urbanization.
- Variations in composition of the population, particularly youth concentration.
- Stability of the population with respect to residents' mobility, commuting patterns, and transient factors.
- Modes of transportation and highway system.
- Economic conditions, including median income, poverty level, and job availability.
- Cultural factors and educational, recreational, and religious characteristics.
- Family conditions with respect to divorce and family cohesiveness.
- Climate.
- Effective strength of law enforcement agencies.
- Administrative and investigative emphases of law enforcement.
- Policies of other components of the criminal justice system (i.e., prosecutorial, judicial, correctional, and probational).
- Citizens' attitudes toward crime.
- Crime reporting practices of the citizenry.