Liptak: Deterrence and the Death Penalty
A column by Adam Liptak in the New York Times examines the debate over whether the death penalty deters murders.
Joanna M. Shepherd, a law professor at Emory University School of Law who has a doctorate in economics and wrote or contributed to several death penalty studies, says:
“I am definitely against the death penalty on lots of different grounds . . . but I do believe that people respond to incentives.” She argues that for deterrence to work, a state cannot employ "a half-hearted execution program,” as evidence of a deterrent effect only appears in states that have had at least nine executions between 1977 and 1996.
Legal scholars and others criticize recent death penalty studies on the grounds that they are "based on faulty premises, insufficient data and flawed methodologies."
Professors John Donohue III, a Yale law professor with a doctorate in economics, and Justin Wolfers, an economist at the University of Pennsylvania, wrote in a 2005 Stanford Law Review article that "the evidence for deterrence is surprisingly fragile."
“It seems unlikely that any study based only on recent U.S. data can find a reliable link between homicide and execution rates.”
The professors point out that "Canada has executed no one since 1962. Yet the murder rates in the United States and Canada have moved in close parallel since then, including before, during and after the four-year death penalty moratorium in the United States in the 1970s."