[Clodius] had noticed that violence and physical force had become the main means of maintaining dominance in Roman politics. Therefore, he abolished the restrictions on establishing new collegia, the old social and political clubs or guilds of workmen, and had them set up through his agents. These guilds were essentially organized and trained as gangs of thugs, and Clodius used them to control the streets of Rome, by driving off the supporters of his political opponents.
These men were attacking any politician who dared to confront their patron, by means of various forms of harassment, including accosting and beating in the streets, loud booing, showering with filth at the games, besieging houses by throwing rocks or even weapons and, at times, even attempting to burn them. Thus the opposition to Clodius was muted and he became the “king of the Roman streets”.
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Then his gangs set up a blockade of his house, forcing Pompeius to stay at home until the end of that year, to avoid the attacks.
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In January 57, one of the new tribunes tried to pass the bill, but his attempt was met by the usual violence and failed, making clear that the domination of the streets and public spaces of Romes by the gangs of Clodius had to be faced with similar violent methods. Pompeius approved for the tribunes T. Annius Milo and P. Sestius to raise their own street gangs in order to oppose Clodius’ thugs, with some gladiator trainers and ex-gladiators as leaders and trainers. Street fighting continued through the first half of 57 but eventually Clodius lost the battle and the bill about Cicero passed.
Clodius subsequently attacked the workmen who were rebuilding Cicero’s house at public cost, assaulted Cicero himself in the street, and set fire to the house of Cicero’s younger brother Q. Tullius Cicero.
In 56 BC, while curule aedile, he impeached Milo for public violence while defending his house against the attacks of Clodius’ gang, and also charged him with keeping armed bands in his service. Judicial proceedings were hindered by violent outbreaks, and the matter was finally dropped.
In the elections of 53 BC, when Milo was a candidate for the consulship and Clodius for the praetorship, violent clashes erupted in the streets of Rome between the gangs of Clodius and Milo, twice delaying the election.
On January 18, 52 BC, Clodius was returning to Rome by way of the Appian Way from a visit to some of his holdings in the hinterlands. Clodius was travelling lightly with a band of 30 armed slaves and, uncommonly for him, without his wife. By chance, Milo was travelling the other way with his wife as well as an escort which included gladiators, and the two groups passed each other. The encounter between the two groups passed without incident until the last pair at the back of each train began a scuffle. It is then believed that Clodius turned back and was wounded by a javelin thrown by one of the gladiators in Milo’s party. He was brought to a nearby inn for his wounds, while his slaves were killed or driven off.
Milo made the decision that a live political enemy was more dangerous than a dead one and ordered that his gladiators kill the injured Clodius. The body was later discovered by a passing Roman citizen and sent back to Rome. There, Clodius’ wife and two tribunes rallied his supporters to use the Curia as Clodius’ funeral pyre, which resulted in the destruction of the Curia Hostilia. This action and the need to restore order in Rome are cited as the key reasons for the Senate’s appointment of Pompey as Consul without colleague.