Claims that executions deter specific numbers of murders rest on weak data

Evidence

A variety of subsequent studies has yielded contradictory findings. Small changes in assumptions in causal models and choice of control factors produce different results (Lamperti, 1996). Despite improved analytic methods, the key issue of whether executions deter homicides more effectively than lifetime imprisonment without parole remains unsettled. Given the insufficient and equivocal quality of the data, claims that each execution saves a specified number of lives are highly questionable. The law professors John J. Donohue and Justin Wolfers described the difficulty of isolating a deterrent effect caused by a few executions within a mix of many other factors that influence murder rates. The 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” (Liptak, 2007). Professor John Lamperti (1996) put it more succinctly: “The signal, if any, is hopelessly buried in the noise.” — Albert Bandura, Moral Disengagement, 1952

Categorization

• QUESTION: Worth chasing: the econometrician-versus-criminologist disciplinary split over whether economic deterrence logic even applies to violent crime.
• corroborated: 2 independent passages support this claim — Albert Bandura, Moral Disengagement: How People Do Harm…, 1952