He was a member of the 10th National People's Congress and served as Chairman of the Standing Committee of the Jinan Municipal People's Congress from 2001 to 2007.
Duan, together with his nephew-in-law, was executed in September 2007 for murdering his mistress, who was killed by a car bomb.
It is considered one of the most shocking crimes involving a Chinese official.
Duan was the sixth provincial-ministerial level official to be executed in China since 1978.