Xinhua reported that the Communist Party Politburo held a special meeting on December 28 and 29, 2015. The discussion at the meeting centered on the “profound lessons [to be learned] from the abuse of power cases of former senior Party officials Zhou Yongkang, Bo Xilai, Xu Caihou, Guo Boxiong, Ling Jihua and others.” Those who attended participated in “criticism and self-criticism” that centered on the Party’s disciplinary regulations and policies. The participants were asked to watch their families closely.
Xi Jinping presided over the meeting and delivered a speech. Xi urged adherence to the "three stricts and three earnests." The phrase referred to being strict about morals, power, and discipline, as well as being earnest about decisions, business, and behavior.
The meeting emphasized that what Zhou, Bo, Xu, Guo, and Ling did illustrates that the seniority of a Party official does not necessarily mean the Party official has a high Party spirit. In fact, without constant self-improvement, the official may totally lose his Party spirit. Xi emphasized that, “By conducting investigations and severe disciplinary actions against them, [we] are being responsible to the Party, to our country, and to the people, as well as to history.”
Source: Xinhua, December 29, 2015