Answer:
Understand your terms. Rome was an empire under the republic. It had expanded and ruled territories under Roman law from Rome. It was an empire under the republican form of government. In the republican form of government citizens were allowed to vote and elect officials. What is commonly referred to as the "Roman empire" is properly called the principate. The principate was governed by a one man rule and even though the offices of the officials remained the same, the Caesar who was in power often appointed men to office as the power was in his hands and no longer in the hands of the people.