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 become empress regnant like Emperor Zhongzong's mother
Wu Zetian and Li Guo'er could be
crown princess. Meanwhile, Emperor Zhongzong's son by a
concubine,
Li Chongmao the Prince of Wen, was named emperor (as Emperor Shang), but Empress Wei retained power as
empress dowager and
regent. Less than a month later, Princess Taiping and Emperor Zhongzong's nephew
Li Longji the Prince of Linzi rose in rebellion, killing Empress Dowager Wei and Li Guo'er. When Dou Congyi heard this, he beheaded his wife Lady Wang and offered her head to Li Longji, trying to save himself. He was not killed, but was demoted to be the prefect of
Hao Prefecture (濠州, roughly modern
Fengyang,
Anhui). He changed his name back to Huaizhen around this time. Sometime thereafter, after Li Longji's father
Li Dan the Prince of Xiang, a former emperor, was restored to the throne (as Emperor Ruizong), Dou was made the secretary general at Yi Prefecture (益州, roughly modern
Chengdu,
Sichuan). In 711, Dou was recalled to the capital to serve as the director of imperial palace affairs (殿中監,
Dianzhong Jian), and in a month was returned to the post of chief imperial censor. He was also given the designation
Tong Zhongshu Menxia Pingzhangshi (同中書門下平章事), making him a chancellor
de facto. Later in the year, he was made
Shizhong (侍中), the head of the examination bureau of government (門下省,
Menxia Sheng), a post considered one for a chancellor. It was said that he was deeply involved in the faction of Princess Taiping, and he often went to her mansion directly after imperial meetings and did what she ordered him to do. Further, at that time, Emperor Ruizong was carrying out an expensive project of building
Taoist temples for his daughters Princesses Jinxian and Yuzhen, who had become Taoist nuns. Many officials tried to dissuade Emperor Ruizong from doing so, but Dou not only pushed for the projects but personally supervised them. He was therefore derogatorily known in a popular couplet as having served as the empress' Azhe and now the princesses' head of household. Soon thereafter, as a part of a major governmental reorganization, he and fellow chancellors
Wei Anshi,
Guo Yuanzhen,
Li Rizhi, and
Zhang Shuo were removed from their chancellor posts, and he was again chief imperial censor. In spring 712, however, he again became chancellor with the designation
Tong Zhongshu Menxia Sanpin (同中書門下三品). In summer 712, a fortuneteller told Dou that he was about to suffer disaster. In fear, Dou offered to resign and serve as a servant at
Anguo Temple (安國寺). Emperor Ruizong agreed. Several days later, he again made Dou chief imperial censor and
Zuo Pushe (左僕射), one of the heads of the executive bureau (尚書省,
Shangshu Sheng), and again chancellor with the designation
Pingzhang Junguo Zhongshi (平章軍國重事). == During Emperor Xuanzong's reign ==