In June of August15, the forces of the Tang Dynasty sent assassins to stab the Prime Minister Wu and the Imperial Pei Du at the head of Chang 'an Street. There was an uproar in the ruling and opposition parties, and the forces of the buffer region further demanded the removal of Pei Du, so as to stabilize the buffer region's "anti-frontier" heart.
Bai Juyi advocated severely punishing the murderer, but because he often wrote allegorical poems, he offended the dignitaries in the DPRK. Because of this, he was classified as "ultra vires" and demoted to Jiangzhou Sima.
Sima, the assistant secretary of the secretariat, was specially used to place "criminals" officials in the middle Tang Dynasty, which belonged to disguised distribution. After that, Bai Juyi began the most difficult six-year relegation career in his life.