DOES PRISON HARDEN INMATES? A DISCONTINUITY-BASED APPROACH By

Some two million Americans are currently incarcerated, with roughly six hundred thousand to be released this year. Despite this, little is known about the effects of confinement conditions on the post-release lives of inmates. Focusing on post-release criminal activity, we identify the causal effect of prison conditions on recidivism rates by exploiting a discontinuity in the assignment of federal prisoners to security levels. We find that harsher prison conditions are associated with significantly more post-release crime. There are similar punishments and crimes called by the same name, but there are no two beings equal in regard to their morals; and every time that convicts are put together, there exists necessarily a fatal influence of some upon others, because, in the association of the wicked, it is not the less guilty who act upon the more criminal, but the more depraved who influence those who are less so. Gustave de Beaumont and Alexis de Tocqueville, 1833 ∗We are extremely grateful for data and helpful conversations to Scott Camp, Gerry Gaes, Miles Harer, Neal Langan, Bo Saylor, and their colleagues at the Federal Bureau of Prisons, Office of Research and Evaluation. We thank Dan Benjamin, Jason Burnett, Judy Chevalier, Ray Fair, Matthew Gentzkow, Edward Glaeser, Claudia Goldin, Larry Katz, David Laibson, Ilyana Kuziemko, Emily Oster, Anne Piehl, Jim Ware and workshop participants at Harvard University, the University of Chicago and Ohio State University for exceptionally helpful comments. †[email protected] ‡[email protected]