The optimum size of a high-security unit for mentally disordered offenders

'Special' hospitals in England (i.e. maximum-security hospitals for mentally disordered offenders, including psychopaths) are thought to be too big. On the other hand, there is concern that there is a size below which maximum security containment could become financially inefficient, inhumane or even dangerous. Is there an optimum solution? In this paper we consider the optimum size of a place for the treatment, and eventually rehabilitation to the community, of mentally disordered offenders held in maximum security. We cannot answer the question of size without taking into account principles of rehabilitation, quality of care, cost-effectiveness, the probable length of stay of the prisoner patient, the architecture of secure units and the psychology of dangerous people. We conclude that the notion of an optimum absolute size for such a place, in terms of either people or bricks and mortar, is a nonsense. However, we do produce an arabesque formula, based neither on numbers nor on acres, but on the nearness to, and the population density of, the community which has attempted to segregate the inmates.