The offense is violence and the circle is divided up into three rings based on the type of violence that was acted upon. For the Outer Ring, bodies are sank into a river of boiling blood and fire. In the Middle Ring, anyone who committed suicide are turned into trees and bushes which are fed upon by harpies. In the Inner Ring are blasphemers and sodomites, laying in a desert of burning sand and burning rain falling from the sky.
The punishment for the ninth circle makes the most sense to me. This circle is for the treacherous, or the betrayers. The punishment is that the sinners are eaten and mangled by Satan, not to mention living the rest of their lives in a frozen world and listen to the weeping of Satan. This circle includes three infamous betrayers in history; Judas Iscariot, Brutus, and Cassius. Dante choses these men because he believes that they deserve the greatest punishment because they have a direct impact on Julius Caesar and Jesus Christ’s death. This punishment is just because it is one of the worst punishments