The legal principle of ne bis in idem restricts the possibility of a defendant being prosecuted repeatedly on the basis of the same offence, act, or facts. This book describes obstacles that stand in the way of a single, autonomous, and uniformly applicable general ne bis in idem principle of EU law.

Questions of the application and interpretation of the ne bis in idem principle in EU law continue to surface in the case law of different European courts. The primary purpose of this book is to provide guidance and to address important issues in connection with the ne bis in idem principle in EU law. The development of the ne bis in idem principle in the EU legal order illustrates the difficulty of reconciling pluralism with the need for doctrinal coherence, and highlights the tensions between the requirements of effectiveness and the protection of fundamental rights in EU law. The ne bis in idem principle is a 'litmus test' of fundamental rights protection in the EU. This book explores the principle, and the way the Court of Justice of the European Union has interpreted it, in the context of competition law and the areas of freedom, security and justice, human rights law and tax law.

This study, written by distinguished scholars in their respective fields, addresses the application and interpretation of the ne bis in idem principle in EU law.

Master's Thesis from the year 2011 in the subject Law - European and International Law, Intellectual Properties, grade: 1,3, Leiden University (Europäisches Rechtsinstitut), language: English, abstract: This thesis looks at the EU ne bis in idem principle. In particular it examines if this principle that no one shall be held liable twice for the same act, contains an enforcement requirement. Because the ne bis in idem principle is codified in different sources of EU law which all have slightly different wordings, a (national) judge may be confronted with the difficult question as to what provision to apply in a given case. The author of this thesis has selected a judgment of a German Court that well illustrates this dilemma and which shows the relevance and topical interest of this problem, for which as yet no clear guidance has been provided by the European Court of Justice (ECJ). In this Boere case a German Court applied the ne bis in idem principle as laid down in Article 54 CISA and concluded that enforcement was an essential element of the ne bis in idem principle. The thesis introduces this case in a well-structured manner and critically reflects upon the judgment of the German Court. By taking this case a starting point, the author sets out clearly which underlying questions concerning the hierarchy between the different sources of EU law must be answered before a conclusion in a particular ne bis in idem case can be drawn. The author of this thesis argues that Article 54 CISA – as applied by the German Court in the Boere case – is incompatible with Article 50 EuCFR, a provision which does not contain an enforcement requirement. She thereby analyses the relation between these two source of law – the Schengen acquis and the EU Charter of Fundamental Rights – in a profound, refreshing and well-substantiated manner. Particularly the discussion of relevant ECJ case-law is good and comprehensive. The author subsequently assesses whether the incompatibility of Art 54 CISA with Art 50 EuCFR (with EU law in general) can be justified. Here again, she addresses a relatively new question. This thesis is well-researched and reasonably convincing. The author has persuasively shown that it would be desirable if the ECJ would give a ruling on the question.

Although Article 23(5) of EU Regulation 1/2003 provides that competition law fines ‘shall not be of a criminal law nature’, this has not prevented certain criminal law principles from finding their way into European Union (EU) competition law procedures. Even more significantly, the deterrent effect of competition law fines has led courts in the Netherlands and the United Kingdom (UK), as well as the European Court of Human Rights, to conclude that competition law proceedings can lead to a criminal charge. This book offers the first book-length study of whether courts do indeed apply criminal law principles in competition law proceedings and, if so, how these principles are adapted to the needs and characteristics of competition law. Focusing on competition law developments (both legislative and judicial) over a period of twenty years in three jurisdictions – the Netherlands, the UK and the EU – the author compares how each of the following (criminal law) principles has emerged and been interpreted in each jurisdiction’s proceedings: freedom from self-incrimination; non bis in idem; burden and standard of proof; legality and legal certainty; and proportionality of sanctions. The author offers proposals involving both legislative and judicial actions, with examples of judges invoking criminal law principles to develop an appropriate level of safeguards in competition law proceedings. The book shows that criminal law can provide a rich source of inspiration for the judiciary on the appropriate level of legal safeguards in competition law proceedings. As such, it provides an important source of information and guidance for lawyers and judges dealing with competition law matters. "The work is well argued and well researched. Indeed, it is almost encyclopaedic in its use and citation of case law and secondary material....This book provides a valuable resource for anyone (whether as advocate, investigator, adjudicator or academic researcher) who wishes to understand how these criminal law principles are used in, and to protect those subject to, administrative law-based competition investigations.” Bruce Wardhaugh (Lecturer at the University of Manchester) Common Market Law Review, 2021, vol 58, issue 1, page 236

This insightful and timely book provides a comparative assessment of selected legal issues emerging from the EU legal context which impact profoundly on the national legal systems. It argues that judicial interaction can answer complex legal questions relating to the implementation of the EU Charter.

Based on author's dissertation (doctoral)--Universiteit Antwerpen, 2011, under title: The Principle of Mutual Recognition in the EU Internal Market and the EU Criminal Justice Area