All the political stars seemed aligned for Sun Zhengcai to be promoted to a top national post in China at the Communist Party’s congress this fall.
His most recent high-profile post was party secretary for Chongqing, a vast city of 30 million where he was sent to clean up a government in the aftermath of a corruption and murder scandal. Last year, President Xi Jinping publicly shook his hand and praised his city.
Then, on July 15, he abruptly vanished.
Within five days of publicly vowing absolute loyalty to Mr. Xi and extolling his “superlative political wisdom,” Mr. Sun was dismissed and put under investigation and has since disappeared, his career terminated by the man he had praised.
The sudden fall from grace was taken as a warning that Mr. Xi will play succession politics by his own ruthless rules.
“Sun Zhengcai was a sacrificial object to send a message across the party,” said Wu Qiang, a current affairs writer and former political science lecturer at Tsinghua University in Beijing. “Xi Jinping has signaled that he doesn’t feel bound by the order of promotion set by the previous generation of leaders.”
The party’s terse public announcement said only that Mr. Sun, 53, had been removed as party secretary of Chongqing. It gave no explanation and, ominously, said nothing about his future. His name has not appeared in official Chinese media since his dismissal.
His replacement was Chen Miner, formerly the secretary of nearby Guizhou Province and a protégé of Mr. Xi since working under him in Zhejiang Province, in eastern China, over a decade ago.
Mr. Sun “was just the wrong guy in the wrong place,” said Joseph Fewsmith, a professor at Boston University who studies Chinese party politics. “Chen Miner seems like one of those people Xi is counting on to get things done.”
Mr. Sun’s fall also demonstrated the power of the roving party investigation teams that Mr. Xi has used to demand devotion and conformity from officials.
Three people who are close to senior officials said that before Mr. Sun was dismissed, he was put under investigation by the party. Two of them said an internal party explanation of his removal did not specify allegations but said investigators had found “violations of discipline,” a vague term that might mean political infractions or corruption. The three spoke on condition of anonymity, citing fear of punishment for discussing internal party affairs. The Wall Street Journal first reported the inquiry.
News outlets in Chongqing were told to stop using Mr. Sun’s keynote slogans for developing the area, according to an internal memo an editor at an official newspaper sent to his staff.
Mr. Sun’s removal appears to undermine the pecking order of elite promotion that had been taking root under Mr. Xi’s predecessors, especially Hu Jintao, the previous president. Mr. Sun’s promotion was never fail-safe, but under the hierarchy created at Mr. Hu’s retirement, he had appeared poised for elevation this year.
“If Sun Zhengcai is not promoted and in fact being brought down, being purged,” said Susan L. Shirk, the chair of the 21st Century China Center at the University of California, San Diego, “that really is an indication that the unwritten rules, or norms, of leadership succession are not being followed.”
She saw the move as part of an effort by Mr. Xi to “consolidate as much power as he can” without being challenged by other members of the party elite.
“There have been people purged before and corruption has been the excuse, too,” she said. “But it seems like there’s been more of that under Xi Jinping.”
Mr. Xi has not commented publicly on the moves, but he appears to be maneuvering to ensure that the Politburo and its all-powerful standing committee are dominated by loyalists.
At the Party Congress this fall, at least 11 of the 25 members must retire, unless an unwritten retirement ceiling is relaxed. They include five members of the seven-member Politburo Standing Committee, the core chamber of power.
Removing Mr. Sun furthers the ascent of Mr. Chen, a politician who has long been close to Mr. Xi, analysts said. For now, Mr. Sun is still a member of the Politburo, but Mr. Chen is likely to take Mr. Sun’s seat on it at the Party Congress.
If the inquiry leads to charges, Mr. Sun will face punishment, or he may get a minor post or quiet retirement, if he survives the scrutiny.
In May, Mr. Xi also installed Cai Qi, an official who worked closely with him in Zhejiang, as party secretary of Beijing, a job that probably puts him on the Politburo. Mr. Xi may also replace the party secretary of Shanghai, another Politburo post, said Bo Zhiyue, an expert on China’s top-level politics, who runs a consultancy firm in Wellington, New Zealand.
“Before the 19th Party Congress, Xi wants to make sure he gets as many seats as possible at the Politburo level,” Mr. Bo said. “Xi’s people have been too junior, so he’s pushing to get them into the right places for Politburo promotion.”
Mr. Xi may go further and bend the informal age rules to let Wang Qishan, his ally in charge of the party anticorruption and discipline commission, stay in office beyond the current retirement ceiling, which usually requires leaders to step down at a congress if they are 68 or older, some party insiders have said. Mr. Wang is 69.
Some have also speculated that Mr. Xi wants to stay in power beyond 2023, when he must retire as president after two terms. There is no formal limit on how long a party general secretary can stay in office. Any decision on that seems far-off. But Mr. Xi could keep his options open by delaying designating a successor.
While it remains unclear exactly what did in Mr. Sun, party investigators questioned his political reliability earlier this year.
Mr. Sun was sent to Chongqing late in 2012, when the city was shaken by the corruption, murder and torture exposed after the previous party secretary, Bo Xilai, fell from power that year. Mr. Bo, an imperious politician, was dismissed and arrested after investigators found his wife, Gu Kailai, had murdered a British businessman. Mr. Bo was sentenced to life in prison for graft and abuse of power.
But while Mr. Bo’s downfall gave Mr. Sun a big political break, it also appears to have figured in his undoing. A stinging party inspectors’ report on Chongqing published in February said that under Mr. Sun, Chongqing had not done enough to eradicate the influence of Mr. Bo and his feared former police chief, Wang Lijun. The inspector who delivered the rebuke was Xu Lingyi, who had worked under Mr. Xi in Zhejiang.
“Party leadership has weakened,” Mr. Xu told Mr. Sun, according to a report from the discipline inspection commission. He laid out other failings in Chongqing, including not enough study of Mr. Xi’s many speeches. “Eradication of the ideological toxic residue of Bo and Wang hasn’t been thoroughgoing.”
Any politician would probably have a hard time erasing nostalgia for Mr. Bo in Chongqing. He remains popular among many residents who liked his aggressive crackdown on crime. But Mr. Sun was contrite.
“This is an alarm bell for us,” he told officials in Chongqing in February.