裁量型追加當事人制度的反思及優化

裁量型追加當事人是我國本土化的追加當事人類型，依審判權自由判斷是否追加當事人，主要表現為被告的追加。裁量型追加過於簡單，僅設“追加”規範，缺乏完備制度內容，依賴實體性司法解釋而缺乏獨立程序地位，脫離了既有民事訴訟理論。實踐中，人民法院極少據此追加當事人，出現“不追加”的怪像，與制度目的呈現出緊張關係。其原因在於，人民法院受當事人訴權的單向約束，裁量權受限，借此查明事實的動力不足，並未針對性地匹配相應的訴訟形態。裁量型追加當事人在程序上是審判權與訴權相互作用的結果，是中間化的追加當事人類型。裁量型追加是實體上應對多數人責任（之債）的訴訟良策，並在特定的連帶責任與不真正連帶責任中發揮作用。以上程序與實體兩方面共同構成了其理論基礎。理論上這一制度應認可裁量型追加在處理複雜糾紛中的特殊作用，可從規範立法表達、明確制度獨立地位、鞏固類似必要共同訴訟和補充後續救濟程序四方面進行優化。

The discretionarily adding parties represents a localized type of adding parties unique to China, relying on judicial discretion to determine the inclusion of additional parties, primarily manifested in the addition of defendants. This mechanism, characterized by its simplistic“addition”norm, suffers from a lack of comprehensive system content, relies on substantive judicial interpretations without an independent procedural status, and deviates from established civil procedural theories. In practice, the People’s Courts rarely invoke this mechanism to add parties, leading to the peculiar phenomenon of non-adding. This situation creates tension with the system’s objectives. The underlying reason is that the courts are unilaterally constrained by the litigant’s right to sue, thereby limiting judicial discretion and resulting in insufficient motivation to ascertain facts, lacking targeted matching with the corresponding litigation model. From a procedural perspective, the discretionarily adding parties emerges from the interaction between judicial authority and the right to sue, serving as an intermediate type of adding parties. Substantively, it offers a strategic solution for litigations involving liability of the majority, playing a role in specific joint and several liabilities and non-genuine joint and several liabilities cases. The theoretical foundation encompasses both procedural and substantive aspects, recognizing the unique role of discretionarily adding parties in managing complex disputes. Optimization should focus on legislative expression, clarifying the system’s independent status, and strengthening necessary joint litigation and supplementary relief procedures