On the Trierarchic Crown, by an Unknown Pleader (19-20)

And then, as if they were not members of a free state, in which because of this fact anyone who chooses has the right to speak, but as if they possessed this right as a sort of sacred prerogative of their own, if any man speaks in your midst in defence of what is right, they feel themselves grossly wronged, and say that he is an impudent fellow. And they have gone so far in their senseless folly, that they think that, if they call a man impudent who has spoken but once, they will themselves be thought good and worthy men all their lives.

Yet it is because of the public speeches of these men that many matters are going from bad to worse, while it is owing to those who honestly oppose them that not everything is lost. Such are the pleaders, then, that my opponents have engaged to speak on their behalf, and so readily open to attack are they themselves for any who wish to speak any ill of them (as they well know); yet they have seen fit to contest this matter, and they have had the audacity to speak ill of another, when they should have been well content to keep out of trouble themselves.