This article explores the role and justifications for EU action in the EU Area of Criminal Justice, also relying on a comparison with the justifications for EU action in the internal market. It distinguishes between a role for the EU as a subsidiary policy actor and as a primary policy actor. By substantiating both models, the article illustrates how the model of the EU as a subsidiary policy actor has been challenged by legislative and judicial developments in the internal market and how these trends were particularly accentuated in the EU Area of Criminal Justice. The EU increasingly regulates areas of non-cross-border crime, as can be appreciated by the shape and the implementation of the competence to harmonise definitions of crimes. And the Court of Justice has unequivocally extended the application of EU criminal law, both substantive and procedural, to internal cases. The article argues that such developments, which build on pre-existing trends in the internal market field, are inevitable in the EU Area of Criminal Justice due to the inherent fundamental rights' sensitive nature of criminal law. A subsidiary, piecemeal approach in criminal justice might safeguard national regulatory autonomy but is hardly affordable as it would challenge general principles of criminal law. Relying only on “legal cross-borderness” as a criterion to justify EU definition of crimes would neglect the harm principle and the legal interest principle. Legal creativity that would stem from limiting EU intervention and safeguarding regulatory competition can be fostered by enlarging EU regulatory tools in this area codifying also decriminalisation competences. Moreover, limiting the application of EU criminal law to only cross-border cases is at odds with the principle of legality in criminal matters and of equal treatment.

中文翻译：

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欧盟作为欧盟刑事司法领域主要规范行为者的新兴角色

本文探讨了欧盟在欧盟刑事司法领域采取行动的作用和理由，还依赖于与欧盟在内部市场采取行动的理由的比较。它区分了欧盟作为辅助政策参与者和主要政策参与者的角色。通过证实这两种模型，本文说明了欧盟作为附属政策参与者的模型如何受到内部市场立法和司法发展的挑战，以及这些趋势如何在欧盟刑事司法领域尤为突出。欧盟越来越多地监管非跨境犯罪领域，这一点可以从协调犯罪定义的能力的形成和实施中看出。欧洲法院明确扩大了欧盟刑法的适用范围，实质性和程序性的，适用于内部案件。文章认为，由于刑法固有的基本权利敏感性，这种建立在内部市场领域已有趋势之上的发展在欧盟刑事司法领域是不可避免的。刑事司法中的一种辅助的、零敲碎打的方法可能会保护国家监管自主权，但很难负担得起，因为它会挑战刑法的一般原则。仅仅依靠“合法跨境”作为欧盟对犯罪定义的正当性标准，将忽视损害原则和合法利益原则。可以通过扩大欧盟在该领域的监管工具以及非刑事化能力来促进限制欧盟干预和保护监管竞争的法律创造力。而且，