The book demonstrates how such systems are not only a mechanical response to a security problem, but are also shaped by other goals, risks, and imperatives, such as maintaining legitimacy, projecting a state-like image, and supporting governance efforts. This work thus identifies and explains some remarkable features of the IRA's pursuit of informers, such as the establishment of 'courts-martial', the granting of 'amnesties', the expansion of social control, the productive function of labelling 'treason' in asserting sovereignty, and the long-term consequences of the issue during transition out of conflict. By exploring the penal logics, practices, and discourses of armed rebel groups - engaged in direct struggle with the state agencies that normally carry out criminal justice - the book aims to expand the study of punishment and society and demonstrate its utility to the understanding of non-state actors.