Democratic Progressive Party (DPP) Chairman Su Tseng-chang (蘇貞昌) has signed a petition and issued an open letter to party representatives to call for the release of former president Chen Shui-bian (陳水扁) on medical grounds.

Su signed the petition — launched by several doctors, including National Taiwan University Hospital physician Ko Wen-je (柯文哲) — after drawing criticism earlier for refusing to sign it despite his verbal support.