The 2008 Census of State and Local Law Enforcement Agencies (CSLLEA) data collection form was mailed to more than 20,000 agencies potentially operating nationwide. This master list was created by compiling information from the following sources:

* The 2004 CSLLEA
* Lists provided by Peace Officer Standards and Training offices and other state agencies.
* A FBI list of agencies requesting new identifiers since the 2004 CSLLEA.

Responses were received through website, fax, and mail options. Responding agencies were screened for eligibility to be included in the final CSLLEA database. Agencies were excluded if any of the following conditions existed on the CSLLEA reference date of September 30, 2008.

* The agency employed only part-time officers and their total combined hours averaged less than 35 hours per week.
* The agency was closed, represented a duplicate listing, or was otherwise an invalid entry.
* The agency contracted or outsourced to another agency for performance of all services.
* The agency did not employ personnel with general arrest powers.
* The agency did not operate with funds from a state, local, special district, or tribal government.
* All sworn officers volunteered their time on an unpaid basis.