Friday, March 24, 2006
Death Penalty Debate
After a quick perusal of a new paper in the Stanford Law Review, it really does put into question the efficacy of the use of capital punishment as a deterrent for violent crime and criminal activity in general. The authors, John J. Donahue and Justin Wolfers:
We find that the existing evidence for deterrence is surprisingly fragile, and even small changes in specifications yield dramatically different results. Our key insight is that the death penalty -- at least as it has been implemented in the United States since Gregg [v. Georgia] ended the moratorium on executions -- is applied so rarely that the number of homicides it can plausibly have caused or deterred cannot be reliably disentangled from the large year-to-year changes in the homicide rate caused by other factors. Our estimates suggest not just "reasonable doubt" about whether there is any deterrant effect of the death penalty, but profound uncertainty. We are confident that the effects are not large, but we remain unsure even of whether they are positive or negative. The difficulty is not just one of statistical significance: whether one measures positive or negative effects of the death penalty is extremely sensitive to very small changes in econometric specifications. Moreover, we are pessimistic that existing data can resolve this uncertainty.
Although, I have not yet read all of it, I would suggest a look over the introduction if you have the time. The paper can be found here.
We find that the existing evidence for deterrence is surprisingly fragile, and even small changes in specifications yield dramatically different results. Our key insight is that the death penalty -- at least as it has been implemented in the United States since Gregg [v. Georgia] ended the moratorium on executions -- is applied so rarely that the number of homicides it can plausibly have caused or deterred cannot be reliably disentangled from the large year-to-year changes in the homicide rate caused by other factors. Our estimates suggest not just "reasonable doubt" about whether there is any deterrant effect of the death penalty, but profound uncertainty. We are confident that the effects are not large, but we remain unsure even of whether they are positive or negative. The difficulty is not just one of statistical significance: whether one measures positive or negative effects of the death penalty is extremely sensitive to very small changes in econometric specifications. Moreover, we are pessimistic that existing data can resolve this uncertainty.
Although, I have not yet read all of it, I would suggest a look over the introduction if you have the time. The paper can be found here.
