Early in the Changqing era (821-824) of Emperor Muzong, Jia Su and Bai Juyi were put in charge of grading a special imperial examination for those with strategies, and it was said that the popular opinion at the time was that Jia and Bai were fair graders.
When Emperor Muzong died in 824 and was succeeded by his son Emperor Jingzong,[REF] Jia was one of the imperial emissaries sent out to the circuits to announce Emperor Muzong's death, and he was sent to the Yangtze-Qiantang River region.