From The Stargate Omnipedia
Tollan legal system. The triad consists of three sides: an archon, a seeker, and a neutral archon. The archons debate the issue until a resolution is reached.
Tollan law forbids a penalty of death. Triad is held as a closed session unless matters of extreme urgency arise.
Pretense - Narim arrives on Earth requesting that a triad be assembled to decide whether or not Skaara will be freed of his Goa'uld.