我國於民國八十六年修憲正式以「雙首長制」定調後,此一全新的憲政架構無論在規範面或實際運作上均引起了各界廣泛討論。而隨著時空推移,加上政黨輪替出現,總統與立法院的不同調,更導致此體制在運作過程中衍生出許多問題。對於我國憲政體制的研究,實不乏學術研究成果,試觀其詳,除了透過傳統制度論的研究方法闡明權力互動關係,乃至於修憲歷史的詳盡回顧外,近年亦有論者採以新制度主義的分析方式,由我國憲改過程論述其間行為者互動,以及制度結構與憲法變遷所依循的路徑,探討雙首長制的發展脈絡。然而,基於新舊制度論一脈相承的特性,加以憲政體制研究中關於「憲法」、「憲政」的概念在學理上實能分別與之產生連結,本文認為兩種制度論的研究方法不能偏廢其一,而應二者互為對照。因此,透過比較的觀點,本文將就我國雙首長制的三大主要問題-總統與行政院院長的權力關係、行政立法兩權的負責機制及閣揆任命權,分由憲法規範、運作面以及憲政精神等面向分別探討,期望依此建立起全新分析的架構,明瞭我國憲政體制真正問題之所在,並進而能覓出因應之道。
Since the 1997 constitutional amendments stipulated the ”semi-presidential” system in Taiwan, this new constitutional system has raised lots of discussions in both normative and operative dimensions. As time goes by, with the first regime turnover, more and more constitutional problems have emerged. Actually, there are many researches on Taiwan's constitutional system. Besides the approach of ”old institutionalism”, recently, the researchers also make use of the ”new institutionalism” approach to argue how constitution changes in Taiwan. However, the old and new institutionalism are historically and methodobogically, derived from the same origin, while the concepts of ”constitution” and ”constitutionalismcan” can also relate to either of then. Therefore, from the comparative viewpoint of old and new institutionalism, this paper will analyze three main problems of Taiwan's constitutional operations revealed by the presidentpremier-Legislative Yuan interactions in theree dimensions, i.e., constitution, constitutional operation and the spirit of constitutionalism. The purpose of this paper is to establish a new analytical framework which can specify constitutional problems effectively, and suggest the solutions too.