There was in Athens (and several other city-states) a smaller body, called the boule, which decided or prioritized the topics that were discussed in the assembly. In addition, in times of crisis and war, this council could also take decisions without the assembly meeting. The council was composed of 500 citizens who were chosen at random and who served for one year.
In addition to all these political institutions were the law courts which were composed of 6,000 jurors and a body of chief judges chosen annually at random. Indeed, there was a specially designed machine of colored tokens used to ensure those selected were chosen randomly, a process judges had to go through twice. It was here in the courts that laws made by the assembly could be challenged and decisions were made regarding exile, naturalization, and debt.
This complex system was, no doubt, meant to ensure a suitable degree of checks and balances to any potential abuse of power, and to ensure each traditional region was equally represented and given equal powers.

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