絞殺效果必然違憲？──從不動產短期交易特銷稅出發

Is the Strangulation Effect Necessarily Unconstitutional?: A Study of Specifically Selected Goods and Services Tax on Real Estate Short-Term Trades

絞殺禁止原則，係指國家所課徵之公課，一旦產生絞殺效果，即可認牴觸比例原則，素為德國與我國之學理與實務所承認。然而，比例原則之審查，向有手段與目的兩個面向，是否果如絞殺禁止原則所稱，僅憑手段導致絞殺效果，毋庸將規範目的納入考量，即告與比例原則有違，實有探究之餘地。對此，本文選擇以不動產短期交易為例，探討倘立法者欲以公課全面抑制不動產短期交易，有何等可能之手段？又是否必然不具實質合憲性？首先，本文從絞殺稅禁止原則之茁生以及憲法基礎出發，參酌德國與我國之實務與學理，爬梳分析絞殺稅禁止原則之內涵、法理與適用範圍。其次，衡諸租稅國原則以及各該公課之性質，倘立法者欲以絞殺效果抑制不動產短期交易，允宜以特別公課為之。末者，在前述基礎上，本文透過對特別公課實質合憲要件之爬剔，嘗試主張，立法論上，若以絞殺性特別公課作為抑制不動產短期交易之手段，確有通過比例原則與平等原則之可能，尚難單憑其絞殺效果，無視其目的為何，即遽謂不具實質合憲性。

Under the Prohibition of Tax Levy Excess principle, any levies imposed by the state that produce a strangle-to-death effect are deemed to violate the Principle of Proportionality (the Principle). However, since constitutional review under the Principle considers both the means employed and the legislative purpose, the analysis becomes more complex. Consequently, room remains for scholarly debate and judicial interpretation as to whether a strangle-to-death effect automatically and invariably constitutes a constitutional violation, regardless of the government's underlying regulatory intent and policy objectives. In addressing this constitutional conundrum, this study systematically examines the substantive constitutionality of governmental levies - particularly those that are not primarily intended to generate fiscal revenue for state coffers - which nevertheless exhibit the problematic strangle-to-death effect. The contemporary and controversial case of short-term real estate trading transactions is utilised as a practical and illustrative example of these complex constitutional issues.
First, academic theories and practical perspectives from Germany and Taiwan are compiled to discuss the origin, theoretical foundations, content, and related controversies of the prohibition against confiscatory taxation. Second, the study argues that, irrespective of the theoretical perspective adopted, the specifically selected goods and services tax on real estate short-term trades is a paradigmatic example of a Strangle to Death Tax. Third, taking the principle of the tax state and the inherent characteristics of various levies into account, this study contends that if the legislature aims to curb short-term real estate transactions through levies, the adoption of Special Common Levies is more appropriate. Finally, by examining the substantive constitutional requirements for such levies, the study posits that those with a strangle-to-death effect can indeed meet both the Principle of Proportionality and Equal Protection. To dismiss the substantive constitutionality of a levy solely on the basis of its strangle-to-death effect without considering its legislative purpose is therefore untenable.