ekklesia

The ecclesia had the power to nominate and elect magistrates who are 
responsible for administering the city's affairs and carrying out the 
decisions of the assembly. The ecclesia, they said, also had the authority to 
pass laws and to decide on issues related to foreign policy, defense, and the 
administration of justice. In addition to its legislative powers, the 
ecclesia also participated in the judicial process in Athens. Still quoting 
from the stud this study.com. The ecclesia members would try cases involving 
serious crimes such as murder and they could impose punishments. This made it 
an important institution for ensuring justice and upholding their rule of law 
in the city.