This book is a treatise on youth justice which examines the treatment, by the criminal law and the criminal justice system, of children who commit serious crimes. It draws on legal, philosophical and Childhood Studies literature to look at the interaction between law and childhood and considers a number of cases, including the murder of James Bulger in 1993 through these lenses, noting the difficulties for legal systems, of accommodating individuals who are, simultaneously, both “child” and “criminal”. The law’s impulse is to protect children and to call to account and punish offenders – aims which sometimes conflict. Other areas of law encounter similar difficulties in the tension between the child’s need for protection and for the nurture of his/her growing autonomy. Drawing on its discussion of this child-criminal paradox, the book examines two examples of the law’s response to children who offend: the age of criminal responsibility and the doli incapax presumption. It proceeds to argue that, in every case, a thorough investigation of the child’s criminal capacity, drawing on developmental psychology, is necessary to provide a fair and rational basis for decisions on responsibility and disposal in respect of such children. It presents a model for achieving this. It also examines the existing response of the Scottish legal system to such children, both in the courts, and through the children’s hearings system. Overall, the argument is for a fair and compassionate approach which takes account of the public interest and the need for public confidence in the criminal justice system.