相對多數決制下為何小黨能生存?－英國與日本的比較分析

Abstract

小黨（minor parties）或第三黨（third parties）存在於不同選舉制度，面臨的困境、挑戰和機會，且其生存方式也不盡相同。相對多數決制與並立制對於小黨的不友善，其制度誘因對選民產生「心理性因素」，驅使其進行策略投票，導致小黨生存不易。 是以，本文欲從「建構小黨發展模式」出發，試圖從杜瓦傑法則的例外情形著手，並找尋是否存在此理論假設的「異例」，同時探討使之成為「例外」的理由以及其如何具體形塑之過程與機制。而本文作為小黨理論的開創性研究，係以「文獻分析法」為主要研究方法，輔以質性為主之「小樣本分析法」，將英國與日本之小黨發展情形作一比較，試圖勾勒出相對多數決制與並立制下的小黨發展模式。 經研究發現，英國小黨其生存方式係以直接衝撞杜瓦傑法則為主，且小黨可分為區域性政黨與非區域性政黨，前者生存原因主要係該小黨選區與文化分歧區域高度重疊，致使文化分歧轉變成政治上對於小黨之支持；此外，由於英國小黨於區域議會與歐洲議會中佔有部份席次，在功能上成為小黨發聲的結構孔道與政治棲所，應得視為其突破杜瓦傑法則的制度性機制。而非區域性政黨－英國自民黨，則是以創造「後天分歧性」為主要原則，具體策略包含在特定選區參選、政策上保持彈性、競選時以「以人領黨」等，主要係以選舉策略來突破杜瓦傑法則。而日本小黨得以生存，如公明黨係與大黨形成「選舉型聯合內閣」，而主要脈絡性因素則是日本留有中選區的制度遺緒、日本政治保有強大的個人集票系統、政黨標籤不明、政黨結構鬆散與政治個人主義顯著等。而選制策略上，日本小黨利用存在於兩票結構的連動效果以獲得支持之外，也應增加選民成全「實現多元代表」之蓄意性動機或誘因，目的係積極促使選民進行分裂投票。 最後，本文認為台灣目前如台聯、親民黨等小黨不僅應保持反執政黨之特性，且須積極把握因合併選舉而擴大的選票票基，更應戮力創造促使選民進行分裂投票的正當理由。

The Duverger’s Law asserts that a plurality rule election system tends to favor a two-party system. However, there have few “anomalies” of such a law, for example, the United Kingdom and Japan, in which existed relatively influential minor parties even under separately the plurality system and parallel system, which possesses the similar effects to the minors. The study aims to answer the question why minor can survive under the tough election system in a comparative perspective. The author compares the living model of the minors between the United Kingdom and Japan, and then provides some suggestions and reflections to the minor parties in Taiwan. The author find out not only does the culture cleavage prompt some region-based parties such as Scottish National Party or Plaid Cymyu survive in United Kingdom, but the cleavage has been transformed into the political supports by regional assemblies and European Parliament. And such a mechanism will provide the minors with living space and as a step-stone toward another political arena except for the England Parliament. Moreover, the biggest third party in England, Liberal Democratic Party has tried hard to create some “artificial cleavage” which can help them to acquire more niches from voters. For example, the party strategically tends to be resilient and flexible, choose designated constituency to campaign, and sustain the anti-government status to attract the floating voters. Compared with the minor parties in United Kingdom which directly confront the Duverger’s Law, the ones in Japan have quite different approaches to make a living. The results show there are several strategies the minors have adopted to struggle for the seats. The first one is to form an electoral united cabinet during the campaign for the exchange of nominations from minor and they will get the support of PR vote from major party as feedback. The second one is foster the voter’s motivation to take on the ticket-splitting behavior by strengthening the connecting effect under the mixed-member two-vote structure. And finally, the minors should promote the images such as “multiple representations” to shape the voter’s behavior’s to intentionally realize the ideal situation by their votes. In the end, the author considers the minor parties in Taiwan should maintain the anti-government status like the Lib-Dem in England to broaden the vote basis. Besides, the enhancing voting ratio after the combination of president and legislator in 2012 does give an applicable niche for the minors to forge themselves to be viable, usable and competitive.