Abstract
Empirical tests of the leading crime theories usually develop measures of the independent variables in a theory or set of theories, and then examine the effect of these measures on crime. This article raises a fundamental challenge to these tests. In the first section, it is argued that it is not possible to fully distinguish between the leading crime theories by focusing on the effect of their independent variables. This is because these theories share many of the same independent variables in common. In the second section, it is argued that the leading crime theories are best distinguished in terms of their specification of crime motives. Such motives may be either positive or negative, and they explain why independent variables lead to crime. With certain exceptions, such motives have been neglected in empirical research. The nature of these motives is discussed, and suggestions for their measurement are offered.