California’s Three Strikes Law Revisited: Assessing the Long-Term Effects of the Law

Previous studies on the three strikes legislation in California draw conclusions based on data immediately following the passage of the law, which cannot account for the full deterrent effect of the law. Moreover, they do not account for the incapacitation effect. Distinguishing between deterrence and incapacitation is important for determining the efficacy of the law. Using data from 1991 to 2009, this paper is the first to examine the long-run effects. Our results show that the law had a significant deterrent effect on all crimes, including non-triggering offenses. Overall, the incapacitation effect is less significant. Further, enhanced penalties cause some felons to substitute between violent crimes and property crimes which carry a lower sentence. However, there is little evidence of substitution within crime categories. Surprisingly however, the added deterrent effect of the third strike is significantly smaller than for the second strike. The small marginal deterrence from the third strike also raises questions about the justification for such extreme severity of punishment.