The Methodological Adequacy of Longitudinal Research on Crime*

This paper argues that the increasing dominance in contemporary criminology of the longitudinal or cohort study is not justified on methodological grounds, that this research design has taken criminological theory in unproductive directions, has produced illusory substantive findings, and has promoted policy conclusions of doubtful utility. In addition, it is noted that longitudinal research is very expensive and therefore has high opportunity costs, costs that have not been properly evaluated. The positive thesis is that many of the apparent benefits of longitudinal research can be obtained by carefully designed and reasonably conceptualized cross‐sectional studies, at substantially reduced cost.