Well-meaning programs can have harmful effects! Lessons from experiments of programs such as scared straight

Despite their importance in assessing the impact of policies, outcome evaluations-and in particular randomized experiments-are relatively rare. The rationalizations used to justify the absence of outcome evaluations include such assertions as we know our programs are working, they can't possibly harm anyone, and if they only help one kid they're worth it. Using preliminary results from a systematic review of nine randomized experiments of the Scared Straight, or prison visitation program, the authors show that a popular and well-meaning program can have harmful effects. They use these results to argue for more rigorous evaluations to test criminal justice interventions.