It is not known when Xiao Zhizhong was born, but it is known that his family was from Yi Prefecture (沂州, roughly modern Linyi, Shandong).
The censors are supposed to serve as the ears and the eyes of the Son of Heaven, and what they submit should directly reach the emperor.
On account of that, he was promoted to be Yushi Zhongcheng (御史中丞), the deputy chief imperial censor, and with Wu Sansi's support, he continued to be willing to indict powerful people, including Li Chengjia, Zhu Qinming, and Dou Xijie (竇希玠).
The chancellors Zong Chuke and Ji Chuna, aligned with Empress Wei, had the censor Ran Zuyong (冉祖雍) accuse Emperor Zhongzong's brother Li Dan the Prince of Xiang and sister Princess Taiping of having conspired with Li Chongjun.
His great faithfulness in yielding the position is known throughout the realm, and this shows that Ran's accusations are false.Emperor Zhongzong accepted Xiao's words and took no further actions on the matter.
In 709, Xiao was made Shizhong (侍中), the head of the examination bureau and a post considered one for a chancellor and was also responsible for editing the imperial history.
Later in the year, he was made Zhongshu Ling (中書令), the head of the legislative bureau (中書省), still a chancellor.
Xiao alone did not do so and was much praised in popular opinion for this, and Emperor Zhongzong once commented, "Among the chancellors, Zhizhong cares about me the most."
[4] In 710, Emperor Zhongzong died suddenly—a death that traditional historians believed to be a poisoning by Empress Wei and Li Guo'er, so that Empress Wei could eventually become "emperor" like Wu Zetian, and Li Guo'er could become crown princess.
Still, he was considered a member of Empress Wei's party and was set to be punished, but Princess Taiping spoke on his behalf, and he was only demoted to be the prefect of Xu Prefecture (許州, roughly modern Xuchang, Henan).
While at Jin Prefecture, Xiao sent messages to Princess Taiping—who by now was in a rivalry with Li Longji, whom Emperor Ruizong created crown prince—offering to join her faction, and Princess Taiping also believed that, because one of Xiao's sons died in the coup, he might be resentful and she might be able to use that to her advantage.
Soon thereafter, the work Xingzuxilu (姓族系錄), which compiled the family trees of prominent clans, edited by Xiao, Dou Huaizhen, Wei Zhigu, Cui Shi, Lu Xiangxian, Liu Cong (柳沖), Xu Jian (徐堅), and Liu Zixuan, was completed, and all of them were awarded with silk.
On July 29,[5] Emperor Xuanzong had Wang Maozhong take 300 soldiers to the imperial guard camp to behead Chang and Li Ci.
[1] It was said that Xiao was thrifty in his living style and free of corruption, but did little to give his wealth to others or to host guests, and therefore his salaries were saved.