Taxation equity may be classified into horizontal equity, where people who are in the same economic position should be taxed the same, and vertical equity, where those who differ economically should be treated differently. In the New Zealand income tax, the vertical equity norm has primarily been achieved by progressive tax rates, and by family-friendly adjustments. Given that the income tax intentionally discriminates between taxpayers on the basis of taxpayer-specific characteristics such as income level and domestic situation, the question arises as to how the New Zealand income tax in its successive manifestations has been justified as fair; that is, what vertical equity in the New Zealand income tax looked like and how it was justified. This thesis considers the practice of the New Zealand income tax since its introduction in 1891 until 1984. By illuminating an employee’s lived experience of the income tax, it illustrates what taxation fairness actually looked like in practice, and contrasts this with the rhetoric of those responsible for the tax. It concludes that the reality of external events, rather than the rhetoric of taxation fairness, appears to have been the main driver of taxation practice. By focusing attention on the experience of the taxpayer, rather than merely on aggregated taxation data, legislative provisions or political discussion, the thesis permits the political rhetoric or fairness to be assessed against the fiscal impact on personal taxpayers. The thesis commences by reviewing certain influences on New Zealand income tax thought: from religion, antiquity, and more particularly from certain key British philosophers. It finds that despite their importance, these do not provide a clear direction for taxation policy. The thesis then shifts from philosophical discussions of what constitutes a fair tax to look at what the income tax actually looked like in the case of a wage or salary earner. It adopts an inductive approach by calculating the effect of the income tax legislation on employees at three income levels and in three domestic situations. The resulting nine cases demonstrate how taxpayers were distinguished for the purposes of vertical equity. Returning to the sources, this thesis then reviews contemporary Parliamentary Debates and Reports for evidence of how Parliament justified the practice of vertical equity in the income tax. Despite frequent appeals to fairness or equity, no clear basis was found. Rather, significant changes to the income tax, and thus to the practice of vertical equity, largely reflected pragmatic responses to political or economic events. Yet once such crises had passed, the income tax, and vertical equity in that tax, did not revert to the pre-crisis shape, but rather conformed to a new paradigm.

稅捐徵免應遵守租稅法定原則，亦須符合實質課徵之公平原則，納稅人依稅法規定負擔應納之稅捐並享有稅捐減免利益，並依實質負擔能力納稅，以符合租稅公平。在土地借名登記契約之稅捐法律關係，應取決於注重真正權利與利益享有之經濟實質關係，或恪遵法律形式之外部關係而定其稅捐法律效果﹖ 為落實稅法秩序，是否容認形式合法性原則之規範價值優先於實質真實之法律原則。稅捐稽徵現況對於減免類型之原因案件，不僅要求在法律形式上應合致稅捐法規範，且經濟實質上須該當於稅捐法規範。 本文擬經由探討租稅法定原則與經濟觀察法，辨正經濟意義的歸屬與租稅構成要件獨立性的概念與涵義，兼顧法律安定性與公平性之調適，深入探討土地借名登記契約之稅捐徵免法律關係，本文發現課徵現況，有違反避免重複課稅及割裂交易認定事實的疑慮。 為兼容並蓄掌握法律形式與經濟實質，試圖提出土地借名登記契約租稅構成要件認定之操作基準。 / The principle of taxation statutory and the principle of substantive taxation equity are the constructive principles of taxation collection. Paying tax by law and being able to pay in substance means that paying tax and being reduction and exemption from tax as well shall be in accordance with the terms prescribed by taxation law and equality in substantive taxation. Does regarding taxation legal relationship of the contract of borrowing other’s name for land registration, the criteria for determining taxation effect whether shall be subjected to economic substantive relationship or the legal external form﹖ The main scope of this study will analyze the principle of taxation by law and the economic substantive survey methodology , in order to understand the concept and meaning with the connection between the taxpayer and the object taxed in economic purpose, to indentify the statutory requirement of tax independently in accordance with taxation laws and free from any interference, to harmonize and balance with stability of the legal order and the principle of equality in substantive taxation. Reviewing the practical experience in relation to cases involving reduction and exemption from taxation, having taken into consideration all the intents of the arguments, we found out any doubts about giving rise to any issue of double taxation between land value increment tax、income tax and business tax, also being partially and selectively authenticating the economic facts. This study has attempted to propose available programs regarding facts to support the cause of taxation between legal external form and economic substance.