Li Daozong was then made the commandant at Ling Prefecture (靈州, roughly modern Yinchuan, Ningxia).
He recalled Li Daozong from Ling Prefecture, first to serve as the director of vassal affairs, and then as the chief judge of the supreme court.
Later on, when Emperor Taizong was planning to attack Eastern Tujue, he again made Li Daozong the commandant at Ling Prefecture.
Upon return, Emperor Taizong increased Li Daozong's fief by 600 households and made him the minister of justice.
Most Tang generals wanted to withdraw, but Li Daozong advocated continued advance, and Li Jing agreed, eventually allowing complete victory, as Murong Fuyun was killed by his subordinates, allowing his son Murong Shun, whom Tang supported, to become khan.
At one point, he was accused of corruption, and Emperor Taizong, in anger, removed him from the post and reduced his fief, but permitted him to return to his mansion as a prince.
Li Daozong met Tibetan escorts at Xingxiuhai (near the Gyaring Lake and the source of Yellow River) and then returned to Chang'an.
During Ansi's siege, part of Ansi's city walls collapsed, and Tang forces had an opportunity to enter, but at that time, Fu Fu'ai (傅伏愛), an officer under Li Daozong, was not paying attention, and instead Goguryeo forces fought out from the breach and captured the part of the offensive earthworks that Li Daozong was responsible for, using it instead for defense.
After returning to Chang'an, Li Daozong offered to resign on account of illness, and Emperor Taizong made him the director of imperial clan affairs, a much less stressful position.
[1] Later, after Zhangsun's and Chu's own downfalls (at the hands of Emperor Gaozong's wife Empress Wu and her associates), Li Daozong's posts were posthumously restored.