This article offers a critique and reconstruction of the concept of medicalization. Most researchers describe medicalization as the redefinition of social problems as medical concerns, and track its spread by the proliferation of disease language and diagnostic categories. Forensic psychiatry and disorders like psychopathy are often cited in these debates. I argue that focusing on discourse overlooks how medical language can justify or mask non-medical practices and outcomes, and lead researchers to identify medicalization where it has not occurred. Building on (...) other critiques of medicalization and recent studies of medical and legal expertise, I propose an alternative conception based on conditions for the performance of medical practice and other forms of expert labor. I distinguish the participation or intervention of medical practitioners from the medicalization of expert practice and identify several institutional factors that facilitate the latter. I illustrate this approach using a critical historical case: the first adult penal psychiatric clinic in the United States, founded by the eminent psychopathologist Bernard Glueck at New York’s Sing Sing Prison in 1916. Glueck’s extensive writings reveal little evidence of medicalization: psychopaths were largely defined and diagnosed according to penal rather than medical criteria, and they received additional punishment rather than treatment. A review of recent research confirms that psychopathy remains primarily a penal rather than medical condition. I conclude that focusing studies of medicalization on practice rather than discourse clarifies the concept and avoids reifying the notion of a medicalized society. (shrink)