論「單一選區兩票制」與「立委減半」並行對台灣政治生態之影響

從2007年開始，第7屆的立法委員選舉將從「複數選區單記非讓渡制」（SNTV）改為「單一選區兩票制」的混合選制（Mixed electoral systems），立委席次也將減半為113席，而任期則由3年改為4年。在這兩項新制度付諸實行之前，各界針對此議題已多有討論，而本文認為，想藉立委選制的改變減緩政黨惡鬥，提升問政品質，恐怕過度樂觀，原因在於單一選區兩票制和立委減半並行之後，未必能達到上述目標，也有可能形成新的問題和弊端。本文試圖藉由一個「憲政體制－選舉制度－政策產出」的架構來探究選舉制度和憲政體系以及政策產出各別之間的關係，並說明選舉制度的重要性，由於這兩層關係，所以新選制施行後，必定會對台灣的政治生態產生影響。首先就憲政體制和選舉制度兩者的革新而言，應存在著位階和先後的關係，因此兩者之間雖然有很大的關聯，但改革應有其先後次序，大的架構確立之後，才能在穩固的基礎下逐步進行各項改革；再來選舉制度對政策產出也有很大的影響，其中牽涉到立法院中的各成員如何形成、行政立法兩者的互動，以及政黨政治的發展，本文假設，當單一選區兩票制實施後，立委的權限會擴張和地方化，對台灣政治生態影響甚鉅。研究方法部份，本文先藉由文獻分析法建立本文的觀點和假設，再透過深度訪談法取得與此議題相關行為者的第一手訪問資料，進一步和本文的論述作一綜合比較，結果發現，單一選區兩票制與立委減半的制度效果恐怕不會如學理預期的顯著，原因在於新選制是否較SNTV制適合現在的台灣，有待商榷；而台灣的政治亂象大多來自藍綠的對立，並非選舉制度的問題，因此想藉由新選制根除政治亂象，可能無法治本；最後，各黨初選機制仍有缺失，加上席次減半可能影響立委未來在立法院的問政品質，所以新選制的制度成效還需時間來驗證。

關鍵字

單一選區兩票制；立委減半；憲政體制；選制改革

並列摘要

The practice of legislative election has gone through a change from “Single Non-Transferable Vote under Multi-Member District” (SNTV) to “Parallel Voting” of Mixed Electoral System since the seventh term in 2007. The legislative seats have been reduced to 113; ant the tenure has been lengthened from 3 to 4 years. Before the new systems take effect, there have been many discussions concerning the subject from all walks of life. In this study, we suggested that the change of electoral system to ease off political contest and competition might not achieve the goals for better political quality in legislative and administrative fields. We concluded that there might be new problems and political abuse of the system occurred after the practice of parallel voting and reduced seats of legislative representatives. The purpose of this study is to investigate the relationship among electoral, constitution system and policy output from a framework of “constitutional system—electoral system—policy output” and explain the importance of electoral system. Because of the multi-layered complexity of the new systems, the ecology of politics in Taiwan is bound to be swayed by the influence. First, for political reform in constitutional and electoral systems, priority of levels should be taken into consideration. Although there is a great deal of connection between the two systems, reform should be put in order; that is, after the major framework is established, then one can proceed with the individual reform gradually on an established foundation. Moreover, the electoral system has quite an impact on political output, especially in terms of the formation of legislative members, the interaction between administrative and legislative division, the development of political party. The hypothesis of this study is that legislative jurisdiction will be expanded and localized after the practice of parallel voting, which would cause a substantial impact on the ecology of politics in Taiwan. We established the research framework and hypothesis by analyzing literature reviews; through depth interviews, we collected first-hand data from the people relevant with this subject. Thereafter, we made a comprehensive comparison with our theory and came to the conclusion that the systems of parallel voting and reduced legislative seats may not have notable outcomes expected by scholars. We believe it is questionable that the new SNTV system is appropriate for the political environment in Taiwan. The political unrest mostly comes from the confrontation of two parties, not because of electoral system; therefore, the reform of electoral system might not be able to eradicate the political chaos. Consequently, the primary election of each party still has pitfalls, plus the fact that the legislative performance may be influenced by the reduced legislative seats. So, the effectiveness of new electoral system is to be determined in the coming future.