State police (United States)

In the United States, state police are a police body unique to each U.S. state, having statewide authority to conduct law enforcement activities and criminal investigations. In general, they perform functions outside the jurisdiction of the county sheriff (Vermont being a notable exception), such as enforcing traffic laws on state highways and interstate expressways, overseeing the security of the state capitol complex, protecting the governor, training new officers for local police forces too small to operate an academy and providing technological and scientific services. They support local police and help to coordinate multi-jurisdictional task force activity in serious or complicated cases in those states that grant full police powers statewide.

A general trend has been to bring all of these agencies under a state-level Department of Public Safety. Additionally, they may serve under different state departments, such as the Highway Patrol under the state Department of Transportation and the Marine patrol under the Department of Natural Resources. Twenty-three U.S. states use the term "State Police." Forty-nine states have a State Police agency or its equivalent, with Hawaii being the only state without a statewide police agency.

The Texas Rangers are the earliest form of state law enforcement in the United States, first organized by Stephen F. Austin in 1823. The original ranger force consisted of ten men charged with protecting settlers from Indian attacks. Though the rangers of this era are today considered law enforcement officers, they rarely wore badges and were little more than volunteers; the Mexican military was officially in charge of law enforcement in the then-Mexican state of Coahuila y Tejas. The Rangers later served as a paramilitary force on the U.S.-Mexico border and in several armed military conflicts, including the Texas Revolution, the Mexican–American War, and the American Civil War. They continued to fill basic law enforcement and frontier protection roles until the close of the "wild west" era. In the early 1900s, they transformed into a criminal investigative agency. The history and legacy of the Texas Rangers has spawned numerous depictions in popular culture. The colloquial image of a Texas Ranger "always [getting] their man" has likewise made the Rangers a revered and highly competitive agency within law enforcement, with fewer than 1 in 100 applicants being considered for a single position.

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