LECS data are primarily collected through BJS' core law enforcement data collection programs: the Law Enforcement Management and Administrative Statistics (LEMAS) core and supplement surveys and the Census of State and Local Law Enforcement Agencies (CSLLEA).

Through the Law Enforcement Core Statistics Program (LECS), BJS combines these collections into a cohesive law enforcement collection program and reshapes their content to focus on agency performance as well as contemporary topics related to agency staffing, regulations, and policies. By redesigning the component collections of LECS, BJS will be able to provide detailed information about LEA performance that aligns these collections with an ongoing national discussion about the need for new measures and metrics for law enforcement agencies.