Drug-use surveillance systems appear in this paper as symptomatic “technologies of suspicion” that constitute a set of empirical modes for producing and interpreting “data” or test results in ways that conflate prediction with prescription, acting as technological forms of supervision, monitoring, supposed deterrence, and ultimately control. Technologies of suspicion are predicated upon a framework of trust; they are deployed within a “system of takings-for-granted” that presupposes trust and thus makes distrust possible. Drug-testing provides an excellent example of the institutionalization of distrust through the deployment of technologies of suspicion not only within institutions but beyond their real and virtual walls. The paper considers the also considers the decentralization and deinstitutionalization of distrust, the capillary dispersion of suspicion throughout the carceral society, and the role of distrust in underwriting the development of certain kinds of knowledge systems and technologies, forms of social and cognitive order, and the functional dispersion of police practices to individuals such as parents, teachers, and peers. Studying why bio-surveillance modalities should diffuse despite their unreliability and their contribution to a generalized climate of suspicion enables the characterization of certain features of the post-sovereign subject in a post-disciplinary regime.