Do NYT:
Does Death Penalty Save Lives? A New Debate
Published: November 18, 2007
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According to roughly a dozen recent studies, executions save lives. For each inmate put to death, the studies say, 3 to 18 murders are prevented.
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The studies have been the subject of sharp criticism, much of it from legal scholars who say that the theories of economists do not apply to the violent world of crime and punishment. Critics of the studies say they are based on faulty premises, insufficient data and flawed methodologies.
The death penalty “is applied so rarely that the number of homicides it can plausibly have caused or deterred cannot reliably be disentangled from the large year-to-year changes in the homicide rate caused by other factors,” John J. Donohue III, a law professor at Yale with a doctorate in economics, and Justin Wolfers, an economist at the University of Pennsylvania, wrote in the Stanford Law Review in 2005. “The existing evidence for deterrence,” they concluded, “is surprisingly fragile.”
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To a large extent, the participants in the debate talk past one another because they work in different disciplines.
“You have two parallel universes — economists and others,” said Franklin E. Zimring, a law professor at the University of California, Berkeley, and the author of “The Contradictions of American Capital Punishment.” Responding to the new studies, he said, “is like learning to waltz with a cloud.”
To economists, it is obvious that if the cost of an activity rises, the amount of the activity will drop.
“To say anything else is to brand yourself an imbecile,” said Professor Wolfers, an author of the Stanford Law Review article criticizing the death penalty studies.
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There is also a classic economics question lurking in the background, Professor Wolfers said. “Capital punishment is very expensive,” he said, “so if you choose to spend money on capital punishment you are choosing not to spend it somewhere else, like policing.”
A single capital litigation can cost more than $1 million. It is at least possible that devoting that money to crime prevention would prevent more murders than whatever number, if any, an execution would deter.
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“These are sophisticated econometricians who know how to do multiple regression analysis at a pretty high level,” Professor Weisberg of Stanford said.
The economics studies are, moreover, typically published in peer-reviewed journals, while critiques tend to appear in law reviews edited by students.
The available data is nevertheless thin, mostly because there are so few executions.
In 2003, for instance, there were more than 16,000 homicides but only 153 death sentences and 65 executions.
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Resumo, potencialmente parcial, mas tentando não ser: há quem concorde com os estudos de regressão parcial (método estatístico que visa ver qual variável se correlaciona melhor com qual, no caso, pena de morte com taxas de homicídios), e há quem ache que o assunto é meio complexo demais, que são poucas execuções ao todo para se poder considerar que sejam dados suficientes para tirar uma conclusão. Os defensores apontam exemplos que lhes parecem mais favoráveis, e como os homicídios diminuiram, os contrários dizem que esses são casos esparsos, não um padrão geral, e que o investimento na pena de morte poderia ser melhor investido em policiamento, que é algo que mais concretamente se sabe que pode diminuir crime e salvar vidas.
