Apparently there is nothing new under the sun. George Stigler, one of the University of Chicago’s all-time great economists, introduced the phrase “marginal deterrence” to economists in a 1970 research paper. The idea behind marginal deterrence is that you want to set penalties such that, even if you can’t commit the criminal from carrying out a crime, he still has incentives to shift his criminal behavior toward less socially costly crimes.
Stigler’s idea wasn’t completely new. I believe the Italian criminologist Cesare Beccaria was writing about it back in the 1700′s, around the time of Adam Smith. So Stigler’s contribution was 200 years late, because at least among economists the idea had been lost.
My former student Emily Feldman informs me now that even Beccaria was a few hundred years too late. Back in 1516, Sir Thomas More already understood the concept. He writes in book one of Utopia:
And surely there is no one who doesn’t know how absurd and even dangerous for society it is to punish theft and murder alike. If the thief realizes that theft by itself carries the same peril as murder, that thought alone will encourage him to kill the victim whom otherwise he would only have robbed. Apart from the fact that he is in no greater danger if he is caught, murder is safer, since he conceals both crimes by killing the witness. Thus while we strive to terrify thieves with extreme cruelty, we really urge them to kill the innocent.
Hats off to Emily for this remarkable discovery.
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“even if you can’t commit the criminal from carrying out a crime, he still has incentives to shift his criminal behavior toward less socially costly crimes.”
It takes him time and money to learn to master other jobs, since crime has been his career for long times, he will agree to do less costly crimes. Learning other stuff has more opportunity cost.
http://www.nguyenhtuan.com
So is murder a Giffen good?
i think the original law book is greek – by a guy called draco, from which we get the word draconian (and also a character in harry potter).
I think his legal code was pretty severe (hence draconian), however, it was the first time specific crimes led to specific punishment rather than just abitary cruelty for unspecified crimes. So in a way he discovered the concept written about by More, Feldman et al, i.e. the idea that a prospective criminal knows where (s)he stands in front of the law.
what about self-fulifilling punishment like waterboarding?- waterboard a thief and he’ll confess to murder (if this doesn’t work, repeat process)
So did the year 1516 incarnation internet trolls respond to Sir More by yelling “Slippery slope!” and asking him to cite his source?
Quote: “The idea behind marginal deterrence is that you want to set penalties such that, even if you can’t commit the criminal from carrying out a crime, he still has incentives to shift his criminal behavior toward less socially costly crimes.”
Shouldn’t it be “even if you can’t prevent the criminal…….” instead of “even if you can’t commit the criminal…….” ?
Nihil novum sub sole. If you search enough you will find a precedent for every economists’ idea. Many of them, in books written by lawyers since the study of Law is much older than the study of economics. Take a look to Ihering’s Scherz und Ernst in der Jurisprudenz (1885) and how he explains the economic sense of bankruptcy laws, for instance.
It would seem that two problems arise from this notion. As with all economics we assume that criminals behave in rational ways. Two, it assumes that criminals fear death above incarceration…again a rational assumption. It could be put forth that all criminals fear all punishment, ergo it would be nice to see some data to confirm these assumptions. Furthermore, without reading, I would believe that any first year criminal justice student could point out the problems with trying to adjust “incentives” for criminal behavior. If we are to understand the “incentives” for criminal behavior we need to understand how every mind works. I agree with marginal deterrence as a concept…but a very weak one. It is not to be confused with a hard and fast rule, simply an additional consideration when increasing or decreasing the difference in severity of punishment between “more” and “less” severe crimes. Remember, the death penalty (if carried out) works as a 100% guaranteed specific deterrent–even if it has varying degrees of effectiveness as a general deterrent.