The opera focuses on four fictitious characters, and an act of forgiveness by Tito that was, frankly, unbelievable. But there is a brief reference in the dialog to a political act by the historical emperor Titus that blows me away for being so far ahead of its time. Here is a fuller description from Wikipedia:
One of his first acts as an emperor was to publicly order a halt to trials based on treason charges, which had long plagued the principate. The law of treason, or maiestas law, was originally intended to prosecute those who had corruptly 'impaired the people and majesty of Rome' by any revolutionary action. Under Augustus, however, this custom had been revived and applied to cover slander or libellous writings as well, eventually leading to a long cycle of trials and executions under such emperors as Tiberius, Caligula and Nero, spawning entire networks of informers that terrorized Rome's political system for decades. Titus put an end to this practice, against himself or anyone else, declaring:
"It is impossible for me to be insulted or abused in any way. For I do naught that deserves censure, and I care not for what is reported falsely. As for the emperors who are dead and gone, they will avenge themselves in case anyone does them a wrong, if in very truth they are demigods and possess any power."
Consequently, no senators were put to death during his reign; he thus kept to his promise that he would assume the office of Pontifex Maximus "for the purpose of keeping his hands unstained". The informants were publicly punished and banished from the city, and Titus further prevented abuses by introducing legislation that made it unlawful for persons to be tried under different laws for the same offense.
This free speech issue is alive and well today, as various laws against slander, libel, intellectual "property" infringement, and yes, treason, are used to silence voices that are exposing corruption. I won't give specific examples here, because I should get to work on solving this problem, I'm sure you can think of examples yourself, and I don't want to get sued!!