The Roman Republic – The Legacy of the Mosaic Judicial System. The Roman Republic, with its separation of powers and rule of law, was essentially a continuation of the Mosaic model of magistrates – where law and justice played a central role in the life of the state. However, under Caesar, this republican system was turned upside down. Caesar – the manipulator of power – overthrew the Senate, abolished the republican system and replaced it with an absolute monarchy, where all power was concentrated in the hands of a single person. From then on, the Roman Republic – the symbol of freedom and the rule of law – was buried under personal ambition and tyranny.