The PNTL was established in May 2002 by the United Nations, before sovereignty was passed to the new state, with a mandate to provide security and maintain law and order throughout the country, and to enable the rapid development of a credible, professional and impartial police service. Recruitment drives were conducted in early 2000, and basic training commenced on March 27, 2000, under the auspices of the United Nations Transitional Administration in East Timor (UNTAET). On August 10, 2001, the East Timor Police Service was officially established, working alongside CivPol, the United Nations Civilian Police Force. It later changed its name to the Timor-Leste Police Service, before finally adopting its current title of the Policia Nacional de Timor-Leste.
It was not until independence, on May 20, 2002, that an agreement was signed outlining the terms and timetable for handing over of full policing duties from CivPol to the PNTL. The PNTL finally assumed responsibility for the whole country on December 10, 2003.
There are at least three special units within the PNTL: the Police Reserve Unit, formerly the Rapid Deployment Service; the Border Patrol Unit (Unidade de Patrulhamento de Fronteiras, UPF); and the Rapid Intervention Unit, or UIR, modelled after the Portuguese National Republican Guardriot police, which served in East Timor before its independence.