This essay studies the "Henry Spearman" detective novel series, wherein a fictional Harvard economist applies economic theory to solve murder cases. Written by professional economists under a pen name, the novels, designed for entertainment and to be assigned to economics courses, espouse a narrow vision of economic common sense through what I call the detective's "economic law enforcement." By interrogating the detective's retroactive construction of symbolic guilt upon suspects, and the authors' use of prosopopœia in verbal debates over economic concepts, it is possible to see how economic orthodoxy is reproduced through the mechanisms of speech.