This chapter is the heart of the book; it presents comprehensive deterrence theory (CDT), the reconceptualization of classical deterrence theory. It identifies the core principle of CDT, additional principles that flow from consideration of the intrinsic elements, and predictions that can be made based on them. The chapter presents both a set of core theoretical arguments and a wide range of corollaries that predict when and how legal punishment deters. The theory argues that deterrence consists of all eight intrinsic elements that individually and collectively deter crime. An essential insight from CDT is that there is no universal deterrent effect of a given punishment. Rather, deterrence involves contingent effects that depend on the configuration of the intrinsic elements. Because these can vary greatly, so, too, can the effects of punishment. This insight has profound implications for understanding the limited state of research to date, limited generalizability of many extant studies, and ineffectiveness of many policies. It also has implications for understanding how policy could be improved.

This chapter discusses the current state of research on deterrence, highlighting critical limitations and, again, the need for an approach that can help to advance the field and policy. Review of extant work on specific and general deterrence, objective and perceptual deterrence, experiential effects, and other areas of deterrence scholarship makes clear that additional problems – besides the overly narrow conceptualization of deterrence inherited from the eighteenth-century accounts of it – exist. These problems include a large body of disconnected and inchoate research, the lack of a unifying theory for connecting research findings or generating new questions, incomplete recognition of the elements that inhere in deterrence and their importance to understanding it, limitations in research that derive from the incomplete understanding of deterrence, and the persistent lack of an answer to a basic question: Do legal punishments deter? This state of affairs is what motivated and guided development of the reconceptualized theory of deterrence, comprehensive deterrence theory (CDT), presented in the book.

This chapter describes steps that can be taken to advance deterrence theory using comprehensive deterrence theory (CDT). It discusses, for example, the possibility of identifying second-level principles that integrate CDT’s first-level principles. There is, too, the possibility of advancing CDT by investigating causes of the intrinsic elements and modifying the principles or creating new ones. Another avenue to pursue entails identifying how deterrent processes and effects may vary across different individuals, groups, conditions, types of crime, and units of analysis. Still other avenues involve incorporating offending theories into CDT and contemplating how deterrence processes may vary when considering offending onset, persistence, and desistance.

This chapter clarifies the theoretical arguments through discussion of issues and questions that may arise in conceptualizing, testing, and evaluating not only comprehensive deterrence theory (CDT) but also, more generally, that can arise in deterrence research. For example, it discusses the nature of punishment. Deterrence scholarship understandably has examined the idea that punishments may deter. What has not been systematically theorized or empirically studied is punishment itself. Historical accounts exist, of course. And numerous scholars certainly have detailed many aspects of certain types of punishment, such as the death penalty. However, deterrence scholarship lacks a coherent foundation for predicting the effects of a wide variety of legal punishments, or how to distinguish when one type of punishment meaningfully differs from another. Similarly, there is a great deal of confusion about legal vs. extralegal punishment as well as specific vs. general deterrence. The chapter examines these and other issues with an eye towards clarifying CDT and charting directions for improving deterrence scholarship.

This chapter revisits the book’s central argument and conclusions from each chapter. It concludes that there has been substantial misunderstanding about core aspects of deterrence, which can be addressed by working from a comprehensive approach to theorizing deterrence and using this approach to guide and evaluate research. The chapter also concludes that most extant deterrence-based policies cannot and will not appreciably deter crime, and may even worsen it. The solution lies in policies grounded in stronger science built on better theory and research. Our sincere hope is that comprehensive deterrence theory (CDT) provides a helpful step in that direction.

This chapter discusses policy implications that flow from comprehensive deterrence theory (CDT). The account points to many implications. Perhaps foremost is the conclusion that there simply is insufficient research to ground deterrence-based policies. There are, though, other equally important implications. The chapter argues that, based on CDT, many deterrence-based policies are likely to be ineffective and may increase rather than decrease crime. At the same time, it is likely that deterrence-based policies can be effective, but only under certain conditions. We extend this reasoning to argue that CDT can be used to inform deterrence-based policies in jails and prisons as well as schools.

This chapter identifies eight intrinsic elements that inhere in all deterrence processes. Identifying the elements is a first step in reconceptualizing deterrence theory. The elements include: (1) costs and rewards of crime and non-crime; (2) interaction of punishment certainty, severity, and celerity; (3) the form of the relationship (e.g., linear or curvilinear) between crime and punishment certainty, severity, and celerity; (4) objective costs and rewards of crime and non-crime, along with perceptions of these costs and rewards; (5) personal and vicarious costs of crime and non-crime; (6) personal and vicarious rewards of crime and non-crime; (7) duration of costs and rewards; and (8) punishment levels, changes, and level–change combinations. As discussed in the chapter, some, but not all, elements have been recognized in prior work. In addition, little consideration has been given to systematically investigating the implications of the intrinsic nature of the elements or how they are involved in deterrence processes.

This chapter discusses the centrality of deterrence to criminological theory and to policy, and then highlights critical shortcomings in classical deterrence theory. It points to critical problems that these shortcomings create, including incomplete or inaccurate understanding of deterrence and ineffective policy. The chapter then describes the motivation for the book, which is to advance theory and policy, the structure of the book, each of the chapters, and recommendations for sequences of chapters readers can follow to pursue their particular interests.