"To date criminologists have a poor record of anticipating future crime rates. As a result, they are ill-equipped to inform policy makers about the impact of criminal justice reforms on future crime. In this report, we assess the factors that explain changes in crime during the past three decades. Our analysis shows that macro-level economic and demographic factors best explain trends in violent and property crime. Together, those factors outweigh the impact of imprisonment rates on crime. We also show that it is possible to lower imprisonment rates without causing an increase in crime. Indeed, several states have done exactly that. Finally, we present models for projecting future crime rates. Based on these models, crime is projected to decrease over the next five years."