Zhu Baoqi should have been a shining example of China's economic miracle in the heartland of the ruling Communist Party. As government funds flooded into industry and construction across his home province of Shaanxi, Zhu became a rich man.

Starting in the 1990s, Zhu invested in former state property, trading up from a cement factory to oil fields, and then to a large coal mine. He moved his family out of cramped, bare concrete workers' housing to a three-story villa surrounded by honeysuckle bushes and fruit trees.