Death Penalty : Deltoid

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Tim Lambert (deltoidblog AT gmail.com) is a computer scientist at the University of New South Wales.

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Death Penalty

Category: criminology
Posted on: March 6, 2006 12:33 PM, by Tim Lambert

When I wrote about David Frum's voodoo criminology in support of the death penalty, I didn't mention any of the recent research that purports to find a deterrent effect for the death penalty because Frum didn't cite it. That research has always seemed suspect to me -- since a very small fraction of murderers are executed in America, it seems unlikely that any effect could be detected above the noise of all the other factors that affect the crime rate. Now a paper by Donohue and Wolfers has been published that is absolutely devastating to the papers that found deterrence. Donohue and Wolfers reanalyze the data used in those papers and found that the deterrence effect goes away if you look at it sideways. For example, one of the most recently touted papers found that each execution deterred 18 murders. However, the description of the model used in that paper was slightly inaccurate. When D&W followed that description the result was that each execution caused 18 murders. Since we don't know which model is the correct one, the data just does not tell whether the death penalty deters or not. Similar problems occur with the other papers that found an effect.
Also on the death penalty: Steve Levitt catches Paul Rubin misrepresenting Levitt's research on the death penalty in Senate testimony.

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Comments

It's not even entirely clear to me why anyone would prefer life in prison to death. And if that preference did exist, would it really be sufficient to make the difference?

Posted by: David Roberts | March 6, 2006 5:42 PM

"I didn't mention any of the recent research that purports to find a deterrent effect for the death penalty because Frum didn't cite it."

What a very odd thing to say. Frum wrote: "So rare a punishment cannot qualify as a deterrent." Which you clearly agree with, since you echo his point.

Oh, any chance of a correction on that earlier post, by the way? Or at least a clarification? You know, about the UK crime survey you claim proves a decline in all crime despite not including rape, murder, crimes against kids, drug dealing, and so on?

Posted by: tim | March 6, 2006 8:26 PM

The question of death penalty is like abortion, it's an ideological question and studies like that are pretty irrelevant.

Posted by: Roman Werpachowski | March 6, 2006 9:16 PM

speaking of odd things to say, frum's comment itself is odd, given two paragraphs later he says:

"If societies want to wind back crime, however, they need to begin by sending a clear message that the sheriff is back in town - that crime won't be tolerated and will be punished to the full extent of the law. And nothing broadcasts that message like restoration of the most extreme punishment."

i may not be an esteemed editor of the bulletin, but that sounds to me an awful lot like saying "the death penalty is a deterrent", only not saying it in those words. it's almost as if frum knows he won't be taken seriously if he explicitly says "the death penalty is a deterrent", but wants to make the point regardless. now why would he do that?*

(*aside from his being a dishonest hack.)

Posted by: snuh | March 6, 2006 10:20 PM

"And nothing broadcasts that message like restoration of the most extreme punishment."

One could justify nastier things then just lethal injection, this way.

Posted by: Roman Werpachowski | March 6, 2006 10:36 PM

The question of death penalty is like abortion, it's an ideological question and studies like that are pretty irrelevant.I'll second that.

Posted by: Ben | March 7, 2006 1:18 AM

You know, about the UK crime survey you claim proves a decline in all crime despite not including rape, murder, crimes against kids, drug dealing, and so on

presuming that you are talking about the British Crime Survey, it does include sexual offences and homicides. Since it is a victim survey and nobody is a "victim" of drug dealing, it does not specifically ask about drugs offences, but it does contain a question about whether people perceive that there is a high incidence of drug dealing in their area. Crimes against under-16s are covered in a separate survey (the Offending, Crime and Justice Survey) and although there are issues with comparability, the trend is also down.

Are you really interested in the numbers? I don't think so.

Posted by: dsquared | March 7, 2006 4:21 AM

"The question of death penalty is like abortion, it's an ideological question and studies like that are pretty irrelevant."

That depends. Yes, it's a moral issue: death penalty will still be wrong even if it's effective in reducing crime/improving the economy/getting the "right" people elected/whatever. Same with abortion, I say. But that doesn't mean studies are worthless. For instance, a recent study in Norway found that a large percentage of women having abortions felt that their boyfriend forced them. That's important both to proponents (because they'd better think of something to do about it!) and opponents (because it illustrates nicely that legality affects what people can be forced to do - the same reason slavery is illegal, and legalized prostitution is problematic).

Posted by: Harald Korneliussen | March 7, 2006 5:34 AM

In my layman's experience, criminology experts going back to the dawn of modern criminology with the French Revolution, child-raising experts, and dog training experts almost all come to the same conclusion: unwanted behaviors are extinguished by the inevitability of detection and the speed of detection; the severity of punishment has a much less potent effect and lapses in the first two can't be made up by increasing severity.

The murderer isn't juggling whether it's worth risking the death penalty or life in prison if he gets caught; he's juggling the chances of getting away with it completely.

Posted by: z | March 7, 2006 10:05 AM

The matters would be clearer if we asked the right question: "is death penalty a stronger deterrent than life imprisonment?" instead of "is death penalty a deterrent?". All punishment deterrs.

Posted by: Roman Werpachowski | March 7, 2006 4:33 PM

Tim You might also find some interesting material in this submission by Columbia University's Professor Jeffrey Fagan to the New York State Assembly Standing Committee hearings on the future of capital punishment in the State of New York.

Posted by: Ken Parish | March 8, 2006 7:33 AM

Z, I remember coming across that, as well. The joke is that, if a small number of executions for a small proportion of illegal killings causes signficant cahnges in overall crime rates, criminals are not exhibiting economically rational behavior.

Posted by: Barry | March 8, 2006 5:52 PM

Tim, the link to the study doesn't work for me - could you check if it is correct? (alternative, could you send it to me? public@kristjanwager.dk)

Posted by: Kristjan Wager | March 28, 2006 9:40 AM

The URL changed on me. I have repaired the link.

Posted by: Tim Lambert | March 28, 2006 10:36 AM

Thanks

Posted by: Kristjan Wager | March 28, 2006 10:51 AM