Abstract

This chapter explores the contributions of neuroscientific evidence of adolescent brain development to youth justice law and policy in England and Wales. It will show that the youth justice system in England and Wales continues not to support children and young people's developmental immaturity and lack of capacity. In English law, children are held criminally responsible and punished for their actions from 10 years of age because it is assumed that they possess the legally relevant capacities necessary for blame. However, the latest neuroscientific evidence suggests that maturation is a long and complex process that stretches into adulthood. The developmental differences in the brain’s biochemistry and anatomy limit children’s ability to perceive risks, control impulses, understand consequences, and control emotions. The prefrontal lobe is involved in the control of aggression and other behavioural impulses related to criminal responsibility. Yet, this lobe is the last area to mature, developing in the twenties rather than the teen years. This evidence highlights that the child’s inexperience and under-developed powers of self-control and reasoning make them prone to acting in ways they cannot help, understand, or intend. These insights show that some children deserve to be excused from criminal responsibility, and abolishing the defence of doli incapax was short-sighted. This chapter will develop the argument that the youth justice system should support the child’s development by more explicitly considering the Child First imperative of promoting their status as capacity-evolving persons. The chapter will conclude by proposing the introduction of a developmental immaturity defence.