Zhou has been a longtime political ally of Bo's and is considered to be close to him, which is why some worry the scandal that brought Bo down may reach far enough to bring the 71-year-old official down with him.
Bo was removed from his post in Chongqing last month and stripped of his membership in the Party Central Committee and the Politburo on April 10. Chinese authorities say he is under investigation for alleged "severe violations" of party discipline, while his wife and household aid have been arrested on suspicion of killing British businessman Neil Haywood. Further details of the scandal are sparse, as the government has been tight-lipped during the ongoing investigation.
The Washington Post reported online speculation is buzzing around Zhou's uncertain future, especially following an April 17 Xinhua news agency editorial which hinted more high-level firings may be on the way. Zhou has also barely appeared in state-run media since Bo's removal, vanishing for a week immediately after.
However, because Zhou is so close to retirement, there are doubts he will be forced out.
"I don't believe that Zhou Yongkang is really in danger now," Li Datong, an independent analyst told the Post. "The party will totally lose credibility in the eyes of the Chinese even if a Standing Committee member has violated the law and the party's discipline rules."