According to Veronique de Rugy a senior research fellow at the Mercatus Center at George Mason University, writing for Reason Magazine, the International Centre for Prison Studies at King’s College London calculated that the United States has an incarceration rate of 743 per 100,000 people, compared to 325 in Israel, 217 in Poland, 154 in England and Wales, 96 in France, 71 in Denmark, and 32 in India.
de Rugy writing for Reason suggested that attempts to estimate the costs and benefits of prison have proved difficult and controversial. In 1987, a National Institute of Justice economist Edwin Zedlewski used national crime data to calculate that the typical offender commits 187 crimes a year and that the typical crime exacts $2,300 in property losses or in physical injuries and human suffering. Zedlewski estimated that the typical imprisoned felon is responsible for $430,000 in “social costs” each year he is not in prison. He concluded that the public benefits of imprisonment outweigh the costs by 17 to 1.
Zedlewski’s findings were rebutted by Boalt Hall Law School penologists Franklin Zimring and Gordon Hawkins, according to de Rugy. The Boalt Hall researchers argued that Zedlewski overstated the net benefit of incarceration. According to a 1991 Brookings paper by John J. DiIulio and Anne Morrison Piehl, making one adjustment to the calculations reduces the benefit/cost ratio to 1.38.
de Rugy writes that economists are getting better at understanding how to keep people out of jail. In a 2007 paper for Economic Inquiry, U.C.–Santa Barbara economist Jeff Grogger found there are large deterrent effects from increased certainty of punishment and much smaller, generally insignificant effects from increased severity. Such findings call into question the economic rationality of increasingly long prison terms. Swift justice trumps big justice.
To read more: http://reason.com/archives/2011/06/08/prison-math