禁止双重危险原则或一事不再理原则可以追溯自圣经、古希腊、古罗马等典籍之记载，虽然有论者认为禁止双重危险原则为英美法系发展之概念，强调被告免于二次遭受司法程序痛苦之危险，与大陆法系中的一事不再理原则强调既判力有所不同，但在两大法系日益交流情形下，应认为两者精神已相通没有强硬区分之必要。又禁止双重危险原则最重要核心莫过于保护被告不因同一犯罪（同一事）而重复遭到追诉、审判及处罚，因此对于何为同一犯罪（同一事）有必要予以定义清楚，本文参酌各国及台湾地区之立法例及案例后，主张以罪名作为判断是否同一犯罪（同一事）之基准有其缺失，尤其是传统案件单一性、同一性理论，更有颠倒法位阶、违背不告不理原则、紊乱举证责任等重大缺失，本文认为德国法上的“相同历史进展过程说”为判断同一犯罪（同一事）之标准应较为合适。纵然禁止双重危险原则已经蔚为国际公约或各先进国家之基本原则，但为兼顾公平正义或被害者之利益，部分国家及台湾地区仍允许就禁止双重危险原则为例外规定，对已经被判决无罪确定之被告再为追诉或再审然而，由我国大陆地区刘涌案以下几则案例凸显了再审程序开启事由相当广泛，即被告几乎不受禁止双重危险保护之问题。本论文建议应参考各国及台湾地区立法例，将再审事由仅限制于事实错误之情形，再区分为为被告利益及不利益再审二种，尤其是为被告不利益再审事由应较为被告利益再审事由限缩。至于原确定判决适用法律错误，则应另透过非常上诉程序处理，且仅限于统一解释法令之必要或救济个案被告两种情形。就刑罚与行政罚乃至于民事赔偿责任之关系，本论文认为行政罚目的在于当下之行政管制，民事赔偿责任之目的在于回复原状，与刑罚之目的并不相同，因此不存在违反禁止双重危险原则问题。最后，就检察官之不起诉决定，本论文主张认为侦查中之检察官决定不宜赋予如同确定判决之既判力效力，以避免审、检分立之违反；但如果检察官是在审判中撤回起诉，则应认为危险已经附着于被告，除非符合再审事由，否则检察官不得再起诉。此外，本论文亦主张英美法之所以限制检察官上诉权，与其陪审团长期历史制度有关，然大陆法系国家既由职业法官审判，因此不必如同英美法，限制检察官不得就一审判决提起为被告不利益之上诉，以兼顾公平正义。
The prohibition of double jeopardy or the principle of ne bis in idem can be traced back to the Bible, ancient Greek and Roman classics, etc. Some said that the prohibition of double jeopardy derives from the development of Common Law （Anglo-American law）, stressing that the defendant is exempted from the danger of the judicial proceeding the second time, which is different from the principle of ne bis in idem in Civil Law that emphasizes res judicata, but as the two legal systems are having even closer exchanges, it should be considered that their principles are exchangeable without the necessity of a strong distinction.Furthermore, the most important core of the prohibition of double jeopardy is nothing more than the protection of the defendant from being repeatedly prosecuted, judged and punished for the same offence （the same matter）, so it is necessary to clearly define what the same offence （the same matter） is. After referring to the legislative examples and cases of each country and Taiwan, this essay claims that there are flaws when we judge the same offence （the same matter） based on its crime name; especially the principles of unity and identity of the traditional cases have material flaws of reversing the legal position, violating the principle of no accusation, no trial, disrupting the burden of proof, etc., so this essay reckons that it is more appropriate to judge whether it is the same offence （the same matter） based on the “Same Historical Development Process” in German law.Despite the fact that the prohibition of double jeopardy has already become the basic principle for the international conventions or developed countries, in order to balance fairness and justice or victims’ interests, some countries and Taiwan still allow the exceptions given the prohibition of double jeopardy, and again prosecute or judge the defendant who has been acquitted. The following cases of Liu Yong in Mainland China highlight the various reasons for retrials, that is, the defendant is hardly protected by the prohibition of double jeopardy. This essay suggests that we refer to the legislative examples of each country and Taiwan, only limit the reasons to mistakes of fact, and differentiate between two types of re-trials: the interest and disadvantage of defendants; especially, the reasons for the disadvantage of defendants should be more limited than those for the interest of defendants. As to the wrong application of laws for the original binding judgment, one should file an extraordinary appeal, and it is only limited to two types: the necessity of the unified interpretation or remedies of the case defendant. Regarding the relationships of criminal penalties and administrative penalties, and even civil liabilities, this essay supposes that administrative penalties are for immediate administrative regulations, and civil liabilities are for restitution, which is different from the purpose of criminal penalties, and therefore they do not run counter to the prohibition of double jeopardy.Lastly, concerning the prosecutor’s non-prosecution decision, this essay claims that the investigating prosecutor’s decision should not be endowed with the equivalent effect of res judicata as in the binding judgment in case of the violation of the principle of the separation of the prosecutor and the judge, but if the prosecutor withdraws a lawsuit on trial, it should be considered the danger has been attached to the defendant, and unless it conforms to the reasons for re-trials, the prosecutor should not re-prosecute. Besides, this essay also claims that why Common Law （Anglo-American law） limits the prosecutor’s right to appeal is related to its historical jury system; however, in the Civil Law-adopted countries, it is professional judges who try the cases, so unlike Common Law, they do not limit the prosecutor to file an appeal for the disadvantage of defendants in the first instance to balance fairness and justice.
