From the Annals of Prescriptivism...

[ricardienne]

Suetonius, Lives of the Grammarians and Rhetors 22
Marcus Pomponius Porcellus, a supremely annoying enforcer of the Latin Language, kept on attacking a grammatical error made by his opponent in a certain trial (for he sometimes pled cases), so vociferously that Cassius Severus appealed to the judges and asked for a recess so that his client could bring in another grammarian, since he now thought he wouldn't be disputing with his opponent about a point of law but of usage.

This same Porcellus, when he had criticized a word in a speech of Tiberius and Ateius Capito affirmed that it was Latin and if it wasn't it certainly soon would be, then said: "Capito's lying. For you can give citizenship to men, Caesar, but you can't give it to words."