Control Yuan Member Kao Yung-cheng Accused of Retaliatory Investigation Against Investigator Yu Zheng-huang, Sparking Abuse of Power Controversy

On June 26, 2023, opposition politicians officially filed a complaint at the Control Yuan against member Kao Yung-cheng for abuse of power. The controversy arose after investigator Yu Zheng-huang—a key figure who accused former Hsinchu Mayor Lin Chih-chien of plagiarism—was targeted by Kao for re-investigation over a minor, resolved case from 2019, shortly after Yu and Lin reached a settlement. Critics and the public strongly suspected the investigation was a "political liquidation" and retaliation by the ruling Democratic Progressive Party (DPP) using the Control Yuan to intimidate Yu. Although Kao claimed the probe was a routine investigation unrelated to the plagiarism case, the highly sensitive timing, combined with Kao's track record of launching politically charged investigations, fueled widespread skepticism. Legal scholars and media outlets criticized Kao for weaponizing the Control Yuan's constitutional powers as a tool for partisan retaliation.