Does Three Strikes Deter? A Non-Parametric Estimation

We take advantage of the fortuitous randomization of trial outcome to provide a novel strategy to identify the deterrent effect exclusive of incapacitation. We compare the postsentencing criminal activity of criminals who were convicted of a strikeable offense with those who were tried for a strikeable offense but convicted of a non-strikeable offense. As a robustness check, we also make this comparison in states without three strikes laws. The identification strategy lets us estimate the deterrent effect non-parametrically using data solely from the three-strikes era. We find that California’s three strike legislation significantly reduces felony arrest rates among the class of criminals with two strikes by 17-20 percent. * Names are in alphabetical order. Eric Helland, Department of Economics, Claremont-McKenna College and RAND, Claremont, California. Alex Tabarrok, Department of Economics, MSN 1D3, George Mason University, Fairfax, VA, 22030. [email protected]. Tabarrok thanks the Center for Study of Public Choice and the Mercatus Center for financial support. Much of this work was undertaken while Helland was a visitor at the Stigler Center. He wishes to thank Sam Peltzman the Olin Foundation and the University of Chicago for their generous support. Helland also wishes to thank the Henri Salvatori Center at Claremont McKenna College for generous financial support. We also thank Joseph Bessett, Bryan Caplan, Robin Hanson, and two anonymous referees for especially helpful and informed comments. The data used in this article can be obtained beginning _____ through _____ from Eric Helland, 500 E. 9th Street Claremont, CA 91711, [email protected]. Helland and Tabarrok 1