再探公共年金制度、法律不溯及既往原則與信賴保護原則──我國軍公教年金改革過渡條款之考察

Revisiting the Public Pension Systems, the Principle of Non-retroactivity and the Principle of Legitimate Expectation: A Review of the Transitional Regulations of Retirement Schemes Reforms for Military Personnel, Public Officials and Public Schools Educators

我國軍公教年金制度自1995年退撫新制實施以來，因過渡條款設計過於優厚，優惠存款制度又未即時落日，產生所得替代率過高的不合理現象，再加上自願退休條件過於寬鬆，在高齡化現象快速進展的作用下，其財務永續性受到嚴峻挑戰。就此，2018年立法院進行軍公教年金制度全盤改革，其所採取之調降退休所得替代率各項措施，亦適用於已退休人員，不少學者認為已發生之退休金請求權法律即不得再予變動，此次年金改革已牴觸法律不溯及既往原則以及信賴保護原則。本文將從公共年金制度之原理說明其跨世代之重分配效果，以及公共年金的權利義務與社會經濟條件、人口結構變遷之間動態調整關係，據以分析既得權主張之盲點，並就司法院釋字第781號至第783號解釋軍公教年金改革釋憲案加以評析。

Since 1995 the financial model of retirement schemes for military personnel, public officials and public schools educators has been transformed from tax-financing into partial funding. At that time, the transitional regulations provided over-compensations for the expected income replacement rate. The temporary schemes of preferential interest rate for lump-sum payments from public insurance and retirement scheme which offered a supplement to the insufficient retirement payment in the past hadn’t been terminated in a rational transitional period correspondingly. These legal backgrounds resulted in an unproportionally high income replacement rate for the retirees. In the following years, the financial sustainability crisis of these retirement schemes has been increasing due to a rapidly aging society without reduced pension of early retirement. In 2018, a comprehensive reform of relevant laws has been introduced. Accordingly, the instruments of reducing income replacement rate have to be applied to the retired personnel. It is argued that the reform is unconstitutional, because the right of pension benefits has been fixed at the time of retirement and becomes untouchable thereafter. With regard to the relationship between financial sustainability of public pension schemes and the permanent change of social, economic and demographic conditions, this article argues that the rights and obligations of participants of public pension schemes shall be dynamically adjusted instead of being fixed. On this theoretical basis, this article will evaluate how the Judicial Yuan (J.Y.) Interpretations No. 781-873 apply the principles of non-retroactivity and protection of legitimate expectation in the constitutional issues of 2018 pension reform.