GlossaryGeography and community profiles
County
A county is a major legal subdivision of a state in U.S.
A county is a major legal subdivision of a state in U.S. geography, with governmental responsibilities determined by state law. In a statistical table, “county” can also be shorthand for counties and county equivalents. A county boundary does not establish that one agency provides every public-safety service throughout all territory inside it.
Geography and government
The Census population-estimates glossary describes counties and equivalent areas as a geographic level used in national statistics. The government organization glossary separately classifies government structures. A statistical unit and a functioning county government therefore need not be identical concepts in every state.
A county can contain several municipalities, unincorporated communities, districts, and overlapping service areas. Public-safety records can be countywide, limited to unincorporated territory, or based on an agency's particular responsibilities. The county name in a dataset title is insufficient to determine coverage.
Population is also a separate measure. A resident count for the full county cannot automatically serve as the denominator for an agency serving only part of it. A rate needs a numerator and denominator covering the same area and period.
Example
Hypothetical example: A county contains three cities and unincorporated territory. A sheriff's published patrol table covers the unincorporated area and one contract city. A Census table reports the entire county's population.
Dividing the patrol table's offenses by the full county population would combine different coverage areas. The resulting number might look like a county crime rate while describing neither the full county nor a properly matched service population. The agency's methodology must establish the correct scope.
Common confusion
A county is not the same as its sheriff's office. The organization can have duties and reporting coverage that differ from the entire county geography.
A county equivalent is an area treated at the same statistical level despite another governmental form. An independent city can be one such entity rather than a city nested within a county.
Local differences
Check the state, geographic code, legal structure, boundary vintage, and source definition. A shared name does not prove identical areas: a county, county government, judicial district, health district, and public-safety service area can differ. For provider information, use the actual agency agreements or service map rather than infer responsibility from the county label.