Benito Mussolini notoriously saw himself as a new Augustus, a 20th-century reincarnation of Rome's first emperor. Sixty years later (and almost as far to the Right), Silvio Berlusconi seems more reminiscent of Augustus's stepson and successor, the emperor Tiberius, who ruled the Roman world from AD14 until he was smothered in his bed in AD37 by the Prefect of the Praetorian Guard (Rome's equivalent of the Head of the Security Services).

Rumour of sexual frolics with adolescent favourites on secluded Mediterranean islands are no doubt the most newsworthy thing that the Italian Prime Minister and Tiberius have in common. Mr Berlusconi has chosen Sardinia as the playground retreat of his old age. Tiberius spent most of his early seventies on the island of Capri, in his so-called Villa of Jupiter (a property that fell not far short of Mr Berlusconi's Villa Certosa in its lavish amenities, boasting heavy security and a thalassotherapy pool, among other luxuries).

Tiberius did not have to worry about prying cameras. But tales soon emerged out about what the emperor was doing on his island. When he went for a swim, gangs of little boys (his “minnows”, as he used to call them) would join him in the water; they had been trained to chase him and nibble between his legs. On other occasions, the elderly emperor preferred the pleasures of voyeurism. According to his Roman biographer Suetonius, “Bevies of girls and young men, collected from all over the place, used to have sex in threesomes in front of him, to excite his waning appetites.” More likely, perhaps, than the implausible rumours of Mr Berlusconi's activities?

But these tales of Tiberius's sexual immorality hinted at something even more rotten at the heart of his political regime. Here too the comparisons with Mr Berlusconi are striking - and rest on something more significant than anything that those ancient or modern “minnows” are rumoured to have got up to. In modern Italy there has been a takeover of the media and a frightening clampdown on journalistic freedom (despite the heroic efforts of newspapers such as La Repubblica to get to the bottom of Mr Berlusconi's secrets, Italy does not now enjoy a free press in any normal sense of the word “free”). Ancient Italy, under Tiberius, saw a similar clampdown on the freedom of the historian.

In AD25, before Tiberius had retired to the fleshpots of Capri, one Cremutius Cordus was put on trial for a new type of offence. He had written a history in which he had praised, as “the last of the real Romans”, Brutus and Cassius, the assassins of Julius Caesar (the adoptive father of Augustus and one of the icons of the imperial regime). In his own defence, Cordus insisted that words were different from deeds and that, anyway, many earlier writers had praised Brutus and Cassius without incurring punishment. In fact, both Julius Caesar and Augustus, Tiberius's predecessor, had tolerated free speech in the writing of history.

Tiberius did not actively attack Cordus, but he listened to the proceedings against him, and to his defence, with a scowl on his face.

Cordus got the message and went away and starved himself to death. The supine senators, who were increasingly willing to do the dirty work of this repressive regime, also got the message. They voted to burn Cordus's books. The Italian electorate appear to be just as prepared to support Mr Berlusconi (his popularity rating is currently the envy of most other Western leaders, despite some cringe-making gaffes, the girls, and a public ticking-off from the Queen). In reaction to yet another onslaught from Mr Berlusconi, Ezio Mauro, the editor of La Repubblica, recently said, “When the powers that be don't explain something, journalism has a job to do.” Cordus would have agreed. In Rome, history-writing had a job to do, which Tiberius and his cronies tried to silence.

Cordus was not the only person to suffer. One of the worst aspects of Tiberius's reign was the growing corruption of the judicial system. In Italy, Mr Berlusconi has miraculously (and with the help of an immunity law) escaped trial, while former advisers, such as David Mills, have ended up with prison sentences. In Tiberius's Rome, “informers” (a private, “for-profit” version of the secret police) made fortunes out of bringing false charges of treason against the innocent.

Former advisers, guilty or innocent, were among the victims here, too. In AD31, Sejanus, Tiberius's one-time right-hand man, was condemned by the Senate and strangled to death. A bloody purge of Sejanus's friends followed.

Tiberius himself remained safe - at least until the new head of the Praetorian Guard, the replacement for Sejanus, decided that it was time to hasten the accession of the deranged Caligula to the imperial throne with a well-placed pillow over the old emperor's face.

Mussolini committed some dreadful crimes under the banner of the first emperor Augustus (the least, if most visible, of which was bulldozing vast tracts of the medieval city of Rome in order to bring to light the remains of the original Augustan monuments). The image of the emperor Tiberius heralds an even darker future for the politics of Italy under Berlusconi.

Yet in the end, even if it is too late for the immediate victims, the wrongs may get righted, or at least the tables turned. When Tacitus - the greatest of all Roman historians - discussed the reign of Tiberius, his hero was, of course, Cremutius Cordus. Not only was Cordus a tragic victim of Tiberius's reign of terror, he was a role model for all later historians who were determined to tell the truth. As Tacitus explains, some copies of Cordus's history were hidden away and so survived the flames; besides, as he put it, “The persecution of free minds only fosters their influence.”

The same may be true of emperor Berlusconi and his Cordus, the editor of La Repubblica.

Mary Beard is Professor of Classics at the University of Cambridge

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