Problem Solving in Criminal Law

What are the acceptable limits of the criminal law? 

This is crucial normative question, and one which has become increasingly important over recent decades with the proliferation of ever more diverse and complex forms of liability. One response is to devise a grand theory of criminal law that seeks to capture its essence within a single definition or formula; providing guidelines on the legitimate and (more importantly) the illegitimate targets of future offences. It is doubtful, however, that any single unifying theory of this kind is possible, and certainly doubtful that the abstract terms necessary for it could provide anything more than vague signalling to law reform. To address the central question then, and to do so in a more applicable manner, a narrower lens is required. Rather than asking for limits to criminalisation in general, we focus on the acceptable limits and fair construction of criminal rules as they apply within different sub-fields. 

Across a series of ‘problem solving’ projects, Professor John Child’s research locates and critically engages with problematic sub-fields throughout the criminal law. This includes work that challenges the design of criminal offences and defences, arguing that certain forms of liability are over-criminalising in their effects (eg, work on complicity, inchoate liability, prior-fault, etc), as well as work defending minimum requirements for criminal liability, such as the voluntary act requirement.

John is currently leading two main collaborative projects: the AHRC funded ‘Criminal Law Reform Now Network’ project, and the British Academy funded ‘Prior-Fault’ project. The aim across both ‘problem solving’ projects is to produce clear and sensible routes forward for law reform.

Criminal Law Reform Now Network

Launched in 2017, the mission of the CLRN Network is to facilitate collaboration between academics and other legal experts to gather and disseminate comprehensible proposals for criminal law reform to the wider community. We include members of the public and mainstream media as well as legal professionals, police, policymakers and politicians. Our proposals might require legislation but we do not restrict ourselves to such projects. Reforms which public bodies such as the Home Office, Police or CPS can bring about by internal policies interest us, as do reforms which require the support of some of the judiciary, bearing in mind the proper judicial constraints on law making. We are ready to consult with and make suggestions to anyone who has the power to bring about reform.

CLRNN Projects include: 

Supported by:

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Prior-Fault Project

This project brings together researchers from law, philosophy and neuroscience to explore criminal blame for conduct that leads to accidental or mistaken harms. For example, where an intoxicated defendant accidentally damages property, or harms a person in the mistaken belief that self-defence was necessary, to what extent (and how) should their choice to become intoxicated effect our judgements of blame? Prior-fault rules, creating liability in these circumstances, can be found across most criminal law jurisdictions; but have been widely criticised for their over-criminalising effects.  

The project is run in collaboration with the Sentencing Council for England and Wales, Australian Law Reform Commission, New South Wales Law Reform Commission, South Australian Law Reform Institute, Tasmania Law Reform Institute, Jersey Law Commission, Law Reform Commission of Hong Kong, New Jersey Law Reform Commission, Scottish Law Commission, as well as several less formal collaborations beyond this. 

This research is supported by the British Academy’s Knowledge Frontiers: International Interdisciplinary Research Projects 2019.

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Research team

Academic outputs



Inaugural lecture: Professor John Child, Understanding crimes across and between events
Problem solving in Criminal Law - Professor John Child