In this book, I argue that American criminal justice is flawed but redeemable. I argue that straightforward, feasible, and pragmatic steps can be taken to diagnose and solve many of the problems with the criminal justice system and the policies, programs, practices, and decisions that comprise it. Not least, I argue that policy makers, administrators, practitioners, and researchers can and should use evaluation to increase criminal justice accountability and effectiveness.

The motivation for the book stems from a desire to help elevate debates about criminal justice policy and to improve the criminal justice system. All too frequently, this system fails to hold offenders accountable, reduce crime, help victims, or operate efficiently. The fact that much of the system's inner workings occur within what might be termed a black box contributes to these problems. Many times, for example, we have little evidence about how, or even whether, policies have been implemented. The “black box” nature of criminal justice is problematic because of the tremendous growth in the size and costs of the criminal justice system. Moreover, it is troublesome because of the risks – such as increased crime, victimization, injustice, and inefficiency – that may result when this system operates with little credible information or evidence about its policies.

Still, strong grounds exist for being optimistic. For example, policy makers and the public increasingly have called for smarter, more effective ways to reduce crime and help victims.