Administrative Litigation Act Article 253-1

Oral argument shall proceed within the scope set out in the notice of appeal.If the appellee, the joined parties under Articles 41 and 42 do not designate an agent to the litigation, or an agent of a party to the litigation, is absent without legitimate reasons on the day of oral argument, the court may render a judgment on the basis of the statements made by the agents to the litigation that are present on the day of oral argument. If the agents of both parties to the litigation are absent without legitimate reasons on the day of oral argument, the court may render a judgment directly without oral argument.
中文原文 行政訴訟法第253-1條
言詞辯論應於上訴聲明之範圍內為之。
言詞辯論期日,被上訴人、依第四十一條、第四十二條參加訴訟之人未委任訴訟代理人或當事人一造之訴訟代理人無正當理由未到場者,得依職權由到場之訴訟代理人辯論而為判決。
當事人之訴訟代理人無正當理由均未到場者,得不行言詞辯論,逕為判決。

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