The New Hampshire State Police is a state police agency within the Department of Safety of the U.S. state of New Hampshire. Police employees of the State Police are ex officio constables and have the primary role of patrolling the state highways, enforcing the laws and regulations of the highway and motor vehicles, and regulations relating to the transportation of hazardous materials. The jurisdiction of the State Police is limited to toll roads, interstate highways and towns or cities under 3,000 people. - Source: Wikipedia