This is the first in a series of posts summarizing the Open Philanthropy review of the evidence on the impacts of incarceration on crime. The full report is available in PDF, Kindle, and ePub formats.
About when Chloe Cockburn joined Open Philanthropy to spearhead our grantmaking for criminal justice reform, I was tasked with reviewing the research on whether reducing the number of people in American jails and prisons might actually increase crime. In effect, we at Open Philanthropy asked ourselves: what if we’re wrong? What if our grantees win reforms that cut the number of people behind bars, and that pushes the crime rate up? How likely is that? And how likely is it that any increase would be large enough to overshadow the benefits of decarceration, which include taxpayer savings and expanded human freedom?
It may seem strange to launch a grantmaking program even as we question its empirical basis. But Open Philanthropy had already invested significant time in studying criminal justice reform as a cause. And practical decisions must always be made in the face of incomplete information, forcing people and organizations to exercise what Herbert Simon called “bounded rationality.” It can be boundedly rational to act on the information gathered so far, even as we gather more.
The final report reaches two major conclusions:
- I estimate that, at typical policy margins in the United States today, decarceration has zero net impact on crime outside of prison. That estimate is uncertain, but at least as much evidence suggests that decarceration reduces crime as increases it. The crux of the matter is that tougher sentences hardly deter crime, and that while imprisoning people temporarily stops them from committing crime outside prison walls, it also tends to increase their criminality after release. As a result, “tough-on-crime” initiatives can reduce crime in the short run but cause offsetting harm in the long run.
- Empirical social science research—or at least non-experimental social science research—should not be taken at face value. Among three dozen studies I reviewed, I obtained or reconstructed the data and code for eight. Replication and reanalysis revealed significant methodological concerns in seven and led to major reinterpretations of four. These studies endured much tougher scrutiny from me than they did from peer reviewers in order to make it into academic journals. Yet given the stakes in lives and dollars, the added scrutiny was worth it. So from the point of view of decision makers who rely on academic research, today’s peer review processes fall well short of the optimal.
The rest of this post elaborates on those conclusions.