The Enforcement Rules of the Prison Act Article 20
To maintain the order and security of Prisons, prisons may require that prisoners wear certain outfits to facilitate identification.
中文原文 監獄行刑法施行細則第20條
為維護監獄秩序及安全，監獄得要求受刑人穿著一定之外衣，以利人員辨識。