1. Assistant Professor of Criminology. She received her Ph.D. in Criminology from the University of Toronto in 2003. Her most recent research has focused on general deterrence as applied to sentencing, the structure of criminal courts and the processing of cases, the role of the Superior Court in the administration of Canadian Criminal law, and policies related to imprisonment
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    1. Professor of Criminology at the University of Toronto. Most of his recent work has been in the area of youth justice. His coauthored book (with Carla Cesaroni) Responding to Youth Crime in Canada, was published by the University of Toronto Press in 2004. He has also carried out research on sentencing and the operation of the criminal courts, and on attitudes (of the public and judges) about various aspects of the criminal justice system. Most recently he has collaborated with Cheryl Webster on the study of policies related to imprisonment in Canada
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    1. The William Simon Professor of Law and Director of the Criminal Justice Research Program at the University of California. He now serves as the first Wolfen Distinguished Scholar at Boalt Hall School of Law at the University of California, Berkeley. He is the author or co-author of many books on topics including deterrence (Deterrence: The Legal Threat in Crime Control, published in 1972) the changing legal world of adolescence, capital punishment, the scale of imprisonment, and drug control. Recent books include The Contradictions of American Capital Punishment (2003), American Youth Violence (1998) and The Great American Crime Decline (2006).
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Research Summary:

In 1999, Daniel Kessler and Steven Levitt published an article that purported to provide support for the marginal deterrent effects of harsher sanctions on levels of crime. Specifically, they concluded that sentence enhancements that came into effect in California in June 1982 as a result of Proposition 8 were responsible for a subsequent drop in serious crime in this state. Our article examines the analyses and findings of this article and suggests that their conclusion of a deterrent impact fails to withstand scrutiny when more complete and more detailed crime data are used and the comparability of “control” groups is carefully examined. In particular, the addition of annual crime levels for all years (versus only the odd-numbered years that Kessler and Levitt examine) calls into question the prima facie support for a deterrent effect presented by Kessler and Levitt. Specifically, it demonstrates not only that the crime drop in California began before, rather than after, the passing into law of the sentence enhancements in 1982 but also that the downward slope did not accelerate after the change in law. Furthermore, the comparability of the two “control” groups with the “treatment” group is challenged, rendering suspect any findings based on these comparisons.

Policy Implications:

Case studies suggesting that crime decreased after the imposition of harsh sentencing policies are often cited as evidence of marginal general deterrence. As has been demonstrated in other contexts, the question that needs to be asked is “Compared with what?” Kessler and Levitt's (1999) article demonstrates that those interested in sentencing policy need to be sensitive not only to the appropriateness of the comparisons that are made, but also to the choice of data that are presented.