How does the society in Gathering Blue maintain itself and control its citizens?

The society in Gathering Blue is led by an oligarchy, a Council of Guardians who enforce the laws and resolve disputes. While the guardians and their functions are rather mysterious to Kira, she eventually learns that the guardians are not above cruel, even murderous behavior. Her father was attacked and left for dead by one of the current guardians who wanted to be appointed to the Council rather than Christopher. It also seems that the Council may have deliberately caused the deaths of one or both parents of Thomas and Jo. The Council is gathering artists whom they can train to carry on the history of the society and to record its future. In fact, "they were forcing the children to describe the future they wanted, not the one that could be." Thus they lock Jo in her room and won't allow her to sing her own songs. Even the adult singer, whom people only see once a year, is actually a captive, as Kira learns when she observes his chained feet during the Gathering.
In the society, the guardians have power over life and death, and the citizens do not have rights. At Kira's trial, although the Council rules to save Kira's life, the chief guardian states to Vandara, "Actually ... you have no rights at all." The guardians evidently enjoy a much higher standard of living than the regular citizens, but there seems to be no thought of revolt. The society easily disposes of "damaged" people, and citizens probably know that the Council can dispose of anyone just as easily. 
The guardians also use the annual gathering, the worship object (cross), and the song, singer's robe, and singer's staff as tools to maintain order and cohesion within their society. Although much of the song is probably unintelligible to the populace, the citizens revere and obey the ritual. Finally, the Council enforces gender roles. Women cannot go on the hunt, and they cannot learn to read.