Tiberius and Caius Gracchus
Plutarch
Plutarch. Plutarch's Lives, Vol. X. Perrin, Bernadotte, translator. Cambridge, MA: Harvard University Press; London: William Heinemann Ltd., 1921.
Therefore it is not just that a tribune who wrongs the people should retain that inviolable character which is given him for service to the people, since he is destroying the very power which is the source of his own power. And surely, if it is right for him to be made tribune by a majority of the votes of the tribes, it must be even more right for him to be deprived of his tribuneship by a unanimous vote.
And again, nothing is so sacred and inviolate as objects consecrated to the gods; and yet no one has hindered the people from using such objects, or moving them, or changing their position in such manner as may be desired. It is therefore permissible for the people to transfer the tribunate also, as a consecrated thing, from one man to another. And that the office is not inviolable or irremovable is plain from the fact that many times men holding it resign it under oath of disability, and of their own accord beg to be relieved of it.