Explicit guidance for sentencing decisions, and an explicit rationale to guide them, has been a notable feature of sentence-reform efforts over recent decades. In England and Wales a system of sentencing guidelines is in place, based on statutory standards and guidelines provided by the Sentencing Council. Meanwhile, an extensive literature on sentencing theory has developed – for example, that based on notions of desert and proportionate sanctions, or on notions of ‘limiting retributivism’ (von Hirsch and Ashworth 2005: ch. 9 and appendix 2).

Yet, curiously, little attention has been paid to aggravating and mitigating circumstances affecting the sentence. The first systematic effort at sentencing guidance in England and Wales, the Criminal Justice Act 1991, established a system of statutory guiding principles; these norms were aimed at helping to establish gradations of sentence for various crimes, based chiefly on offence-seriousness. However, the legislation omitted any guidance on aggravating or mitigating circumstances affecting sentence. It was only a decade and a half later, in 2004, that the Sentencing Guidelines Council (since replaced by the Sentencing Council of England and Wales) adopted a list of aggravating and mitigating factors. Sentencing theorists and scholars have, if anything, been still more neglectful of the subject; this is the first major book devoted to the topic.