State police (United States)

In the United States, the state police is a police body unique to each U.S. state, having statewide authority to conduct law enforcement activities and criminal investigations. In general, state police officers or highway patrol officers, known as state troopers, perform functions that do not fall within the jurisdiction of a county’s sheriff (Vermont being a notable exception), such as enforcing traffic laws on state highways and interstates, overseeing security of state capitol complexes, protecting governors, training new officers for local police forces too small to operate an academy and providing technological and scientific services.

Source: Wikipedia — State police (United States) (CC BY-SA 4.0)