Joyce, Theodore. 2004. "Did Legalized Abortion Lower Crime?" Journal of Human Resources 39(1): 1-28.

In this paper I compare changes in homicide and arrest rates among cohorts born before and after the legalization of abortion to changes in crime in the same years among similar cohorts who were unexposed to legalized abortion. I find little consistent evidence that the legalization of abortion in selected states around 1970, and then in the remaining states following Roe v. Wade, had an effect on recent crime rates. I conclude that the dramatic association as reported in a recent study is most likely the result of unmeasured period effects such as changes in crack cocaine use.

Ted Joyce is a professor of economics at Baruch College and a researcher with the National Bureau of Economic Research. This work was supported by a grant from the Open Society Institute. John Donohue III and Steven Levitt graciously shared their data and programs, which greatly facilitated the author's analysis. They also provided helpful comments on earlier drafts. The author also thanks Greg Colman for research assistance and Robert Kaestner, Michael Grossman, Sanders Korenman, Philip Cook, Phillip Levine, John Lott, and numerous seminar participants for helpful comments. He states that the views and errors in this manuscript are his and not those of the Open Society Institute, Baruch College, or the National Bureau of Economic Research. The data used in this article can be obtained beginning August 2004 through July 2007 from Dr. Ted Joyce, National Bureau of Economic Research, 365 Fifth Avenue, 5th Floor, New York, NY 10016-4309.