was the assembly of the centuries (i.e., soldiers). The president of the Comitia Centuriata was usually a consul. The centuries would vote, one at a time, until a measure received support from a majority of the centuries. The Comitia Centuriata would elect magistrates who had the imperium powers (consuls and praetors). It also elected censors. Only the Comitia Centuriata could declare war, and ratify the results of a census. It also served as the highest court of appeal in certain judicial cases. The assembly of the tribes (i.e., the citizens of Rome), the Comitia Tributa, was presided over by a consul, and was composed of 35 tribes. The tribes were not ethnic or kinship groups, but rather geographical subdivisions. The order that the thirty-five tribes would vote in was selected randomly by lot. Once a measure received support from a majority of the tribes, the voting would end. While it did not pass many laws, the Comitia Tributa did elect quaestors, curule aediles, and military tribunes. The Plebeian Council was identical to the assembly of the tribes, but excluded the patricians. They elected their own officers, plebeian tribunes and plebeian aediles. Usually a plebeian tribune would preside over the assembly. This assembly passed most laws, and could also act as a court of appeal. Magistrates Each republican magistrate held certain constitutional powers. Each was assigned a provincia by the Senate. This was the scope of that particular office holder's authority. It could apply to a geographic area or to a particular responsibility or task. The powers of a magistrate came from the people of Rome (both plebeians and patricians). The imperium was held by both consuls and praetors. Strictly speaking, it was the authority to command a military force. In reality, however, it carried broad authority in the other public spheres such as diplomacy, and the justice system. In extreme cases, those with the imperium power were able to sentence Roman Citizens to death. All magistrates also had the power of coercitio (coercion). This was used by magistrates to maintain public order by imposing punishment for crimes. Magistrates also had both the power and the duty to look for omens. This power could also be used to obstruct political opponents. One check on a magistrate's power was called Collega (collegiality). Each magisterial office would be held concurrently by at least two people. Another such check was provocatio. While in Rome,