Published online by Cambridge University Press: 28 November 2008
This paper is an attempt to make more specific the familiar sociological notion of the ‘unanticipated consequences of social action’. Reasons for the relative neglect by practitioners and analysts of the side-effects of legislative action are suggested. The discussion of unintended and unanticipated social action is related to the work of classic sociologists, to theorists of diffusion, and to the study of innovations and inventions. Previous studies of Congress (including those by the author) are shown to have focussed on process and representation at the expense of the legislation itself and its consequences, examples of which are considered in this paper. An economic law about the creation of demands by legislation, explaining the development of many side-effects, is proposed. The relationship between rules expressed in enactments and the whole system of formal and informal rules in the life of a society is explored. A number of considerations for future work are outlined, and the paper concludes by arguing that greater awareness of the problem of side-effects will have two valuable consequences: (1) the identification of general tendencies may help to avoid gross perversion of purposes; (2) even where there are no clear regularities of response, the observation of patterns of side-effects and their correlation with other factors may enable analysts to anticipate likely side-effects and suggest readjustments.