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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Montesquieu also made a big deal about this in his “The Spirit of the Law”. In the section “Of the just Proportion between Punishments and Crimes,” he writes:
“It is a great abuse amongst us to condemn to the same punishment a person that only robs on the highway and another who robs and murders. Surely, for the public security, some difference should be made in the punishment.
“In China, those who add murder to robbery are cut in pieces:53 but not so the others; to this difference it is owing that though they rob in that country they never murder.
“In Russia, where the punishment of robbery and murder is the same, they always murder.54 The dead, say they, tell no tales.”
I wonder if he got this from More
That Thomas More . . . he was a man for all seasons!
How does this concept of marginal deterrence relate to the opposition of the “Three Strikes” law? Opponents of three strikes claim criminals with 2 strikes are more likely to committ violent crimes because the incentive is shifted to more costly crime for that third strike. I believe there was a series of posts already about it.
Well, yes, this is a book I read in high school English class called Utopias and Distopias.
Ok, nothing to do with the post, but I notice that the NYT has put ads in the feed for this ‘blog. I wouldn’t mind, except that the feed doesn’t even show the whole post! Just a summary! One or the other, guys – ads and full content, or a teaser to get me to come and view the content here with ads. Argh.
There might be some people even before Thomas More that had this same idea, and a little bit of more research is needed to find him.
Incentives are the only way people will change their behavior. In real life, a good example are per-unit taxes; if people are charged a per-unit tax, they are going to reduce the total quantity demanded since the price of the good will increase. As More said, if people are treated the same for murdering or for stealing, more murders are more likely to be occurring. If people kill their victims, they are creating a safety net since the only witness is going to be dead by the time the trial begins. If murders are to be decreased, the penalty for murdering should be notably harsher than that of stealing.
“commit the criminal from” –> “prevent the criminal from”, I assume.
“even if you can’t commit the criminal from carrying out a crime”
I think they meant “…prevent the criminal…”