Rome was responsible for instituting a checks-and-balances form of government that limited the amount of power held by one person. It also granted its people some power in the formation of government through the election of representatives to the Senate.
The three-branch governmental system of the United States is based on that of Rome, which also had executive, legislative and judicial branches. In the Roman model, citizens elected Senators. The definition of who classified as a citizen in Rome changed significantly over the course of the empire. Typically, though, low-class citizens who were slaves or did not own land were not allowed to vote. Women were also forbidden to vote. Senators were nearly always wealthy nobility. As opposed to a purely democratic model, however, the Roman people did not elect their leader. However, the lower classes elected Tribunes, who could veto unpopular decisions made by the Senate. When the Senate felt that circumstances required only one individual to be in power, it would appoint an individual who temporarily had absolute rule. Citizens had influence only over the Senate, however. Caesars were determined by lineage and presumed to be descendants of the gods. The judicial branch of the Roman government also had a system of laws called The Twelve Tables that insured everyone equal consideration in matters of the law.