The Allied Tribunal was a Federation Alliance group that negotiated the Dominion War Accords.
After the Female Changeling had the Dominion forces surrender and signed the treaty, she was held in Deep Space 9's holding cells until she could be turned over to the Allied Tribunal for her war crimes trial. (DS9 short story: "Requital")
Kira Nerys gave a testimony to the Tribunal about her assistance to Corat Damar's Cardassian Liberation Front. Her testimony was broadcast on a newsfeed. (DS9 novel: This Gray Spirit)