The Acamarian Ruling Council was a legislative body of the government of Acamar III. It was composed of representatives of the many factions on the planet. According to the Gatherer Chorgan, the "real power" of the government laid with the Council, and not with another unnamed governmental body also composed of representatives.
When negotiating the peaceful return of the Gatherers to Acamar III in 2366, one of Chorgan's demands of Sovereign Marouk was three seats on the Ruling Council. Marouk claimed that no group had that much representation on the Council. (TNG: "The Vengeance Factor")