Such was the distribution of the three powers in the city. But it was far from the same in the provinces. Freedom was in the center, and tyranny in the extremities.
While Rome dominated only in Italy, the peoples were governed as confederates. The laws of each republic were followed. But when she conquered farther afield, when the senate could not immediately keep an eye on the provinces, and the magistrates who were in Rome could no longer govern the empire, prætors and proconsuls had to be sent out. At that point that harmony of the three powers was over. Those who were sent had an authority that combined those of all the Roman magistracies, nay, even that of the senate, even that of the people.  They were despotic magistrates who were quite appropriate for the distance of the places to which they were sent. They exercised the three powers ; they were, if I may use this term, the pashas of the republic.
We have said elsewhere that the same magistrate in the republic must hold both civil and military executive authority. For that reason, a republic that conquers can hardly communicate its government and rule the conquered state in accordance with the form of its constitution. Indeed the magistrate it sends to govern, holding both civil and military executive authority, must have the legislative authority as well, for who could make laws without him ? He must also have the judicial authority, for who would judge independently of him ? Therefore the governor the republic sends must have the three authorities, as was the case in the Roman provinces.
A monarchy can more easily communicate its government, because of the officers it sends, some have the civil executive authority and others the military executive authority : which does not bring despotism with it.
It was a privilege of great consequence for a Roman citizen to be able to be judged only by the people. Otherwise he would have been subjected in the provinces to the arbitrary power of a proconsul or a proprætor. The city did not feel the tyranny that was exercised only over subordinated nations.
Thus, in the Roman world, as in Lacedæmon, those who were free were free in the extreme, and those who were enslaved were enslaved in the extreme.
While the citizens were paying tributes, they were levied with very great equity. They followed the system of Servius Tullius, who had distributed all the citizens in six classes in the order of their wealth, and fixed the share of taxes in proportion to the share which each had in the government. The result was that they bore the magnitude of the tribute because of the magnitude of their influence, and were consoled for their modest influence by the modesty of their tribute.
There was another admirable thing, which is that the Servius Tullius’s division by classes being, so to speak, the fundamental principal of the constitution, it happened that equity in the levy of tributes was of a piece with the fundamental principle of the government, and could not be taken away unless it was too.
But while the city was paying tributes with no difficulty, or was paying none at all,  the provinces were being ravaged by the knights who were the republic’s tax farmers. We have spoken of their harassments, and all of history is full of them.
“All of Asia awaits me as its liberator,” said Mithridates,  so great was the hatred provoked against the Romans by the rapine of the proconsuls,  the extortions of the financiers, and the calumnies of the judgments.” 
That is why the strength of the provinces added nothing to the strength of the republic, and on the contrary only weakened it. That is why the provinces regarded the loss of Rome’s freedom as the era when their own was founded.