He wrote that his experience growing up in the White Terror drove his commitment to Taiwan independence.

He refused to take the classes on Sun Yat-sen Thought (國父思想), which did not become optional until 2006, and handed back his National Taiwan University graduation certificate.

When the police attempted to break into his office in order to arrest him on April 7, he committed suicide by self-immolation.

Cheng's widow, Yeh Chu-lan, held senior positions in the Democratic Progressive Party administration between 2000 and 2005.

[4] On 22 December 2016, the Executive Yuan announced that 7 April every year would become Freedom of Expression Day to commemorate his death.

[5] In November 2013, the National Cheng Kung University renowned for its political sciences studies held a vote to choose the name for a new square.