On the afternoon of May 17, 1989, Deng Xiaoping invited all Chinese Communist Party (CCP) Politburo Standing Committee members to convene at his home. Zhao Ziyang, Li Peng, Qiao Shi, Hu Qili, and Yao Yilin were present; Yang Shangkun was present as a non-voting member. Wang Ruilin was in charge of taking minutes. At the meeting, the group analyzed the situation in Beijing. Finally, Deng Xiaoping made a decision: "The development of the situation further proves that the 'April 26 Editorial' is correct. The reason why the student movement is not subsiding lies within the Party, in Zhao [Ziyang]'s 'May 4th' Asian Development Bank speech." Deng Xiaoping then decided to transfer troops to Beijing and enact martial law. According to "The Critical Moment – Li Peng Diaries", Li Peng, Yao Yilin, and Qiao Shi all agreed, while Hu Qili expressed concern about the situation; only Zhao Ziyang was opposed. At the meeting, Deng appointed a three-member team composed of Li Peng, Yang Shangkun, and Qiao Shi to be responsible for implementing martial law.

"The Tiananmen Papers" and the book "Behind the Scenes of the June 4th Massacre: The Martial Law Forces of June 4th" record what happened next: After Deng Xiaoping signed the order sending in the troops, Xu Qinxian, Commander of the 38th Group Army, refused on grounds of conscience to execute the order, and left the army, citing sick leave. Zhou Yibing, commander of the Beijing Military Region, urgently reported this to the Central Military Commission. Yang Shangkun completely lost his temper after hearing about it; he immediately relieved Xu Qinxian of his post as Army Commander, and had him arrested for court martial. During the interrogation, Xu calmly told the interrogators: "The People's Army has never in its history suppressed the people; and I absolutely cannot sully that history." In the end, he was sentenced to five years in prison. However, he pleaded not guilty, saying only, "Those who are not the saints of history, are the sinners of history!"

References: "The Critical Moment – Li Peng Diaries"; "The Tiananmen Papers"; "Prisoner of the State: The Secret Journal of Premier Zhao Ziyang"; "Behind the Scenes of the June 4th Massacre: The Martial Law Forces of June 4th"