台灣半總統制下的二元行政互動與民意向背：以2000-2008年民進黨執政時期為例

由總統和總理所構築出的雙元行政架構，是半總統制最重要的制度特徵，也是半總統制在運作上最容易產生憲政爭議的環節。在制度設計上，總統和國會各自享有獨立的正當性來源，而總理的正當性卻可能間接來自於國會或是總統。因此，雙元行政架構可能呈現水平的對等關係，也有可能是一種層級關係。然而，制度設計和憲政實際運作也有可能產生落差，關鍵之一就在於社會意向如何界定體制下的行政首長？本文分析民調資料發現，政治知識較多的受訪者，或是對於政治較有興趣者，縱然是在陳水扁總統聲望相對低迷之時，仍然支持以其為中心的行政主導權（以支持特定人事任命方式與支持一致性政府為代表），換言之，民意對半總統制的想像，有可能驅使台灣的半總統制朝向了總統領導的隸屬式二元行政。

關鍵字

二元行政；半總統制；民意；分立政府

並列摘要

In semipresidentialism, both the president and the premier play important roles. The way that they exercise political powers and interact with each other defines actual exercise of the dual executive constitutional system. In theory, both the president and the parliament have separate legitimacies that flow from distinctly different origins. Both the president and individual congressperson are electorally elected. Yet, the legitimacy of the power of the premier must come from either the president or the assembly as a whole. There is no third origin. Thus, the dual executive system might function in a way that the survival of the premiership is subject to the president or in another way the same survival is subject to the assembly alone. Which one is likely to happen in part depends on public opinion. We find that politically sophisticated voters or voters who are interested in politics are likely to support the specific exercise the premier should follow the presidential leadership. We speculate that this public trend at least in 2000-2008 motivated the semipresidentialism in Taiwan to develop in favor of the President at the expense of the assembly.