Late Chinese Communist Party chief, Zhao Ziyang, toppled for opposing the 1989 crackdown on democracy protesters in Tiananmen Square, asked party leaders in 1997 for his freedom, arguing that his detention was illegal.
Sunday marks the 17th anniversary of the crackdown in which hundreds, possibly thousands of people, were killed when army troops fought their way into the centre of Beijing to clear protesters from the square.
In a copy of a letter dated October 13, 1997, and seen by Reuters on Thursday, Zhao warned the powerful Politburo Standing Committee that "those who come after us will hardly regard the house arrest and loss of citizens' rights of a party member who had different opinions as a glorious page in party history".
Zhao died under house arrest at age 85 on January 17 last year.
In September 1997, during the 15th Party Congress, Zhao wrote to the party arguing that the official verdict labelling the 1989 protests a "counter-revolutionary rebellion" was groundless and said the use of force was uncalled for.
That letter prompted the party to increase security around Zhao, who had been under house arrest since the suppression of the protests on June 4, 1989.
Both letters are the subject of a new book being published in Hong Kong.
"From the moment I sent it I was no longer allowed to have visitors or to leave my house," Zhao said in the October letter, addressed to the seven-man Standing Committee led by Jiang Zemin.
"I hope that these blatant and outrageous acts that are being perpetrated under the noses of the central leadership will be stopped.
"I hope my house arrest is lifted soon and that my personal freedom is restored so that I don't have to live out the remainder of my days in loneliness and confinement." Zhao asked rhetorically of his home detention: "Is this not a crude trampling of the socialist system of rule of law?
"It is unavoidable that people will place my treatment and pronouncements from the 15th Party Congress about the principle of 'rule of law' side by side and draw their own conclusions about the trustworthiness of those pronouncements," he wrote.
The party has remained nervous about Zhao's residual influence and has tried to erase him from public memory, blanking out his role in economic reforms that turned China from a economic backwater into a powerhouse.