Law enforcement describes the agencies and employees responsible for enforcing laws, maintaining public order, and managing public safety. The primary duties of law enforcement include the investigation, apprehension, and detention of individuals suspected of criminal offenses. Some law enforcement agencies, particularly sheriffs' offices, also have a significant role in the detention of individuals convicted of criminal offenses.
BJS maintains several national data collections, covering federal, state, and local law enforcement agencies and special topics in law enforcement. Data are typically collected directly from law enforcement and related agencies, including crime laboratories, police departments, sheriffs' offices, and training academies. The most recent tool to access incident-based data on crimes recorded by law enforcement is the Law Enforcement Agency Reported Crime Analysis Tool (LEARCAT).
Most data collections are conducted every 2 to 4 years and report aggregate findings. From these collections, BJS publishes national estimates for personnel, equipment, operations, policies, budgets, and job functions across agencies.
As of fiscal year 2020, BJS estimated about 137,000 full-time federal law enforcement officers. The largest federal law enforcement agency is the U.S. Customs and Border Protection, which employed almost 47,000 full-time officers in 2020.
One difference between a sheriff's office and police department is the jurisdiction that each type of agency covers. While both sheriffs' offices and police departments are law enforcement agencies, sheriffs' offices have countywide jurisdiction and police departments' authority is limited to specific cities, municipalities, towns, or villages. In addition, sheriffs' offices are generally empowered by the state to serve counties and independent cities, while police departments are established under municipal regulations. The head of a sheriff's office is a sheriff who is usually an elected official. The head of a police department is usually the chief, who is typically appointed by a government entity, such as mayor, city manager, or a commissioner.
In 2020, about 14% of full-time sworn officers employed by local police departments and sheriffs’ offices were female. As of 2020, 4% of local police chiefs and 1% of sheriffs were female. About 9% of intermediate supervisors (those between chiefs and sergeants or first-line supervisors) in local police departments and 10% in sheriffs’ offices were female. About 10% of first-line supervisors (sergeants) in local police departments and 12% in sheriffs’ offices were female.