Sun joined Communist Party of China (CPC) in July 1988. He was a member of the CPC Central Committee since 2007. Since November 2012, Sun has been the Communist Party Secretary of Chongqing, an interior municipality, and a member of the Politburo of the Communist Party of China. Before that, he served as the Party Secretary of Jilin province, and Minister of Agriculture of China.
Sun is the youngest member of the 18th Politburo, and one of only two members born after 1960, the other being Hu Chunhua. As such, Sun and Hu were considered to be a leading candidate for a top leadership position in the "6th Generation of Chinese leadership". However, Xi Jinping, the General Secretary of the Communist Party of China, changed the game by abandoning the successors designated by his predecessors.
In July 14, 2017, Sun was removed from the post of Communist Party Secretary of Chongqing, and investigated for wrong-doings. On July 24, the Chinese official news agency reported that Sun violated CPC's disciplines. On September 29, Sun was stripped of his CPC membership, fired from his government position, and charged for crime. On May 8, 2018, Sun was sentenced for life in prison.
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