The Senate, surrounded, made an effort to throw Tiberius out. It was too little, too late. Years of free reign allowed Tiberius to crater public support in institutions like the criminal courts. Sapped from within by division, the Senate found itself unable to control even the execution of its own laws.

Finally free of rules Tiberius had rendered obsolete, the Senate assembled its own violent mob. Led by the Pontifex Maximus, the chief priest of Rome’s civic religion, senators attacked Tiberius in the Assembly. Some, lacking knives, swung clubs fashioned from the legs of shattered Senatorial benches. Only a few refused to participate in the murder.

After his death, Tiberius’ younger brother Gaius succeeded him as Tribune. The populares weren’t going away. The slow corrosion Tiberius set in motion continued to spread until the Republic’s final collapse, under Caesar at the Rubicon, almost a century later.

Tiberius demolished Romans’ high-minded belief in the sustaining power of political customs and traditions. In a few minutes of violent fury, the Senate had proven Tiberius right. Norms that had protected the Republic from strongman authoritarianism for centuries had shattered. Rebuilding them proved too costly.