The report addresses a key concern for policy makers regarding whether deterrence is better achieved by increasing the likelihood of apprehension or increasing the severity of sanctions. Overall, the report concludes that:

• Enhancing the certainty of punishment is far more likely to produce deterrent effects than increasing the severity of punishment.

• Particularly at high levels of incarceration, there is no significant public safety benefit to increasing the severity of sentences by imposing longer prison terms.

• Policies such as "three strikes and you're out" and mandatory minimum sentences only burden state budgets without increasing public safety.

• Evidence-based approaches would require increasing the certainty of punishment by improving the likelihood of detection.

At a time when fiscal concerns have propelled policymakers to consider means of controlling corrections budgets, the findings on deterrence suggest that a focus on examining harsh sentencing practices is long overdue. In many cases prison terms could be shortened without having any adverse effects on public safety.