The Dai Li was originally created by Avatar Kyoshi, sometime between 270 and 82 BG, to preserve the cultural heritage of Ba Sing Se in response to a peasant uprising against the government of the 46th Earth King. Kyoshi founded the Dai Li and trained its initial members. They became known as the Dai Li.' ― Avatar Kyoshi to Aang. They became Earth Queen Hou-Ting's trusted enforcers, supporting her regime and aiding her plans. After the war, however, they regained the trust of the Earth Kingdom's government and began to serve again as the monarchy's secret police, only this time with direct loyalty to the crown itself. The Dai Li's corruption and decadence was so advanced that they later came under the command of Princess Azula, relinquishing any loyalty to the Earth Kingdom, and assisting the Fire Nation in the capture of Ba Sing Se. After 79 AG, Grand Secretariat Long Feng was able to conspire with the Dai Li and effectively rule Ba Sing Se, reducing the position of the Earth King to nothing more than a figurehead. The Dai Li became corrupt over time and did not fulfill the purposes proposed and intended by its founder. The organization was founded by Avatar Kyoshi with the aim of 'protecting the cultural heritage of Ba Sing Se', effectively protecting the Earth King's interest against subversive individuals and groups.

The Dai Li is the elite secret police force of Ba Sing Se who work to capture, interrogate, and imprison political dissidents. ' Long Live the Queen' Image gallery (33)

Avatar the last airbender season 2 episode 17 dailymotion