What kinds of consideration should guide decisions about the scope of the criminal law? This chapter compares the ways in which German and Anglo-American theorists have tackled this question. After some comments on what it is to criminalise conduct, and on the kinds of reason that an inquiry into principles of criminalisation should aim to identify, it offers some historical background to the contemporary debates. It then turns to a critical comparative discussion of two popular principles of criminalisation, the Rechtsgutslehre and the Harm Principle, in the course of which it also attends to Legal Moralism, and to the role of the Proportionality Principle – a principle explicitly central in German theorising, and at least implicitly essential to Anglo-American theories. Finally, it considers some alternative principles of criminalisation, and asks whether we should look not for a systematic account of ‘the principles of criminalisation’, but for a messier, more pluralist account of the range of considerations (principles, reasons) that should bear on criminalisation decisions.

This introductory chapter first outlines the aims and history of the international project on Core Concepts in Criminal Law and Criminal Justice. The aims have been inspired by the increasing globalisation of criminal law and criminal justice, which has led to a growing desire to develop common approaches to common problems and to learn from the diversity of current practice in different countries. This has been reinforced by the internationalisation of criminal justice in international and mixed criminal tribunals. There is now a need to engage in a multi-jurisdictional and comparative conceptual analysis not provided by previous comparative projects, which typically focus on specific topics or issues. The chapter then provides an overview of the chapters in the volume, each of which aims to uncover underlying commonalities and differences, and to explore the scope for constructive assimilation or reform. Finally, the chapter comments on plans for the future.

Criminal law and criminal justice are becoming increasingly globalised. In open societies, the era in which individual jurisdictions developed their own codes, statutes and systems of justice with no regard to other systems and countries is long over. There is a growing desire to develop common approaches to common problems and to learn from the diversity of current practice in different countries. This development has been reinforced by the internationalisation of criminal justice in international and mixed criminal tribunals. However, attempts at trans-jurisdictional discourse are often hampered by mutual misunderstandings. Some problems are linguistic: although English is the new lingua franca of international and comparative criminal law, not all foundational concepts of criminal law and justice originate in the English-speaking world; some of them are rooted in civil law jurisdictions, such as France, Germany and Italy. The translation of these concepts into English is subject to ambiguity and potential error: the same term may assume different meanings in different legal contexts.