The three levels, or types, of law enforcement in the United States are local, state and federal. The tiers of law enforcement allow authorities to operate on small, intermediate and large scales.
The first tier of law enforcement is local, which includes city and county police as well as the sheriff's department. The next level includes law enforcement organizations such as the highway patrol and the state department. The federal level includes such federal agencies as the Federal Bureau of Investigation, Drug Enforcement Administration and the United States Marshals Service, all of which are placed under the authority of the nation's Department of Justice.