Why is Chenxi Du Yuan locked up?

Chenxi Du Yuan framed Jingxiu's family, so he was locked up. Skyclan and the inferno fight, while the mountain elves wait and see, and they don't help each other. Later, skyclan won, and Du Yuan defected like skyclan, slandering Jingxiu's father, that is, he took refuge in the inferno as a Buddhist, killed his family as a warlord who defected to skyclan, and was finally locked up.