Chang was first elected to the legislature in December 1998, as a
Democratic Progressive Party representative of Taipei County.
Taiwan Solidarity Union candidate
Liao Pen-yen was expected to claim some of Chang's vote share in 2001,[3] but both were elected to office. Chang received support from the DPP to run for a third term in 2004, but lost.[4][5]
During his first term on the
Legislative Yuan, Chang drew attention to a number of environmental concerns, including pollution of the
Kaoping River,[6] and the environmental effect of the
Longmen Nuclear Power Plant.[7][8] He worked with
Chai Trong-rong to pass stricter law against electoral fraud.[9][10] Additionally, Chang backed efforts to regulate imported drugs.[11]
Chang commented frequently on exchanges between Taiwan and China, mainly in relation to tourism.[12] In August 2000, he called out
Taipower for importing Chinese gravel illegally for use in building the Longmen nuclear plant.[13] Later that year, he opined that an increase in Chinese visitors would expose Taiwan to increased espionage.[14][15] In March 2002, Chang criticized brokers that defrauded Taiwanese students who wished to pursue higher education in China.[16][17] He was supportive of an initiative allowing children of
taishang to study in Kinmen, rather than the Chinese educational system.[18] In October 2002,
John Chang announced that 121 lawmakers had signed his petition advocating airline flights across the Taiwan Strait.[19] One of the signatories was Chang Ching-fang, but he pulled his support days later.[20] Among Chang Ching-fang's counterproposals included that flights from China to Taiwan transit in Okinawa,[21] and that Taiwan's government lift select restrictions on Chinese entrepreneurs to elicit further investment in Taiwanese real estate.[22] Chang supported
Chen Shui-bian's decision to shift Cross-Strait policy away from "no haste, be patient."[23] However, Chang was largely critical of its replacement, the
three links.[24][25][26] In 2004, Chang claimed that China treated Taiwanese businesspeople unfairly, especially those who supported the
Democratic Progressive Party.[27][28][29]
Chang Ching-fang maintained an interest in national security. In June 2000, Chang asked the
Control Yuan to investigate a former
National Security Bureau official who visited China days after retirement.[30] In October, Chang submitted evidence in a separate legal case implicating the NSB's Liu Kuan-chun, who was suspected of embezzling money from the agency.[31][32] Chang reported to the NSB in March 2002 that Liu was in Canada.[33]
In January 2002, Chang and
Yeh Yi-jin accused several of their legislative colleagues of accepting bribes.[36][37][38] In April, Chang accused legislator
Wang Chung-yu, former president of the Association of Industry for Environmental Protection ROC, of using the group's funds improperly.[39]
In November 2003, Chang alleged that
James Soong had an affair with Yang Yun-tai.[40][41] Members of Soong's
People First Party filed a lawsuit against Chang.[42] Yang did the same, and the court ruled in her favor in August 2005.[43]
In December 2003, Chang called a press conference to present evidence that Pan Jung-kuang had joked about
Chen Shui-bian while giving a lecture.[44][45] Pan apologized after Democratic Progressive Party members filed suit against him.[46]
In February 2004, Chang sued
Thomas Lee for libel, because Lee had accused Chang of involvement in
black gold politics.[47][48] Chang later filed a related lawsuit against Chen Yu-hao.[49][50][51]