Constitutional Court Procedure Act Article 93

(Court Dress and Seating Arrangement)Justices, attorneys, and clerks shall wear gowns for all proceedings of the Constitutional Court.The court dress and the seating arrangement in the courtroom shall be decided by the Judicial Yuan.
中文原文 憲法訴訟法第93條
大法官、律師及書記官於憲法法庭執行職務時,應服制服。
前項人員之服制及法庭之席位布置,由司法院定之。

English translation for reference only; the Chinese text prevails. Not legal advice.