Also known as the Navajo Nation Police, this entity is a law enforcement agency on the Navajo Nation Reservation. The Navajo Tribal Police were originally established in 1872, four years after the Navajo were released from incarceration in Fort Sumner in southeast New Mexico after their forced "Long Walk" from Canyon de Chelly in northeast Arizona in 1864. Manuelito, the great Navajo warchief, known for his resistance to Mexican and U.S. invasions of Navajo territory, was appointed the first "chief" of the Navajo police. Before this time, civil law enforcement had been handled by the Federal Government’s Branch of Law and Order. Despite its initial success, the Navajo Tribal Police was dissolved in 1975. The Navajo Nation Police was reinstated in 1989 upon request from the Navajo Tribal Council.
The first Indian police forces were established in the mid-1800s, with the creation of the Federal reservation system. Initially, these forces were given some measure of autonomy, but self-policing was almost entirely eliminated in the late 1800s and early 1900s, during the Assimilation and Allotment Era. The New Deal's Reorganization Era of the 1930s and 1940s gave back some agency and self-defining rights to Indian Nations, but the Tribal Elimination policies of the Second World War and post-war era brought about devastating effects to systems of tribal government and policing. Following the 1960s civil rights movement, issues of minority recognition and rights gathered momentum and public support, and with the Self-Determination Era of the 1970s Native peoples in the U.S. were able to regain substantial autonomy from federal governance.
Today Native American tribes across the U.S. have their own police forces that function, on reservation lands, much like local or state police units outside the reservation. Tribal police officers have law enforcement authority only inside the reservation, but work closely with state and federal police agencies.