Econintersect: The reflex reaction answer would be increased rates of incarceration, but that would be wrong. A study by Oliver Roeder, Lauren-Brooke Eisen and Julia Bowling of the Brennan Center for Justice at the New York University (NYU) School of Law finds that incarceration ranks low on the list of causative factors for lower crime rates over the past several decades.
In fact the research concludes that mass incarceration had negligible crime control benefits over the past twenty years and limited effectiveness over the ten years prior to that. Factors that are correlated with lower crime rates include modernized policing practices, and expanded treatment and rehabilitation programs, increased personal incomes, aging population and more effective education. In short, one might say: It's the economy, stupid.
The declining return on incarceration investment is displayed in the following graph.
In 1981, for every 100 additional prisoners incarcerated 6 fewer crimes were committed. That is already a very poor return on incarceration investment. But by 2000 and since there are only 2 fewer crimes committed for each 100 additional imprisonments.
Click on the cover page below to read the 139-page report:
- What Caused the Crime Decline? - PDF (Oliver Roeder, Lauren-Brooke Eisen and Julia Bowling, Brennan Center for Justice, NYU School of Law, February 2015)
- What Caused the Crime Decline? - Publication announcement and presentation (Brennan Center for Justice, NYU School of Law, 12 February 2015)