That's the title of a news release issued by the National Research Council announcing a major study capital punishment and deterrence. Here's the full text of the news release:
Research to date on the effect of capital punishment on homicide rates is not useful in determining whether the death penalty increases, decreases, or has no effect on these rates, says a new report from the National Research Council. The committee that wrote the report evaluated studies conducted since a four-year moratorium on the death penalty was lifted in 1976, and it found that the studies do not provide evidence for or against the proposition that the death penalty affects homicide rates. These studies should not be used to inform judgments about the effect of the death penalty on homicide, and should not serve as a basis for policy decisions about capital punishment, the committee said.
The lack of evidence about the deterrent effect of capital punishment -- whether it is positive, negative, or zero -- should not be construed as favoring one argument over another, the report stresses. "Fundamental flaws in the research we reviewed make it of no use in answering the question of whether the death penalty affects homicide rates," said Daniel S. Nagin, Teresa and H. John Heinz III University Professor of Public Policy and Statistics at Carnegie Mellon University Pittsburgh, and chair of the committee that wrote the report. "We recognize that this conclusion may be controversial to some, but no one is well-served by unsupportable claims about the effect of the death penalty, regardless of whether the claim is that the death penalty deters homicides, has no effect on homicide rates or actually increases homicides."
The key question, the report says, is whether capital punishment is less or more effective as a deterrent than alternative punishments, such as a life sentence without the possibility of parole. Yet none of the research that has been done accounted for the possible effect of noncapital punishments on homicide rates.
The committee also found that studies made implausible or unsupported assumptions about potential murderers' perceptions of and response to capital punishment. Many studies did not address how perceptions are formed and simply inferred that potential murderers respond to the objective risk of execution. This inference ignores the fact that determining the objective risk poses great complexities even for a well-informed researcher, let alone a potential murderer. For instance, only 15 percent of people who have been sentenced to death since 1976 have actually been executed, and a large fraction of death sentences are reversed. Furthermore, estimates of the deterrent effect of the death penalty were based on unfounded assumptions, for example, that the effect of capital punishment is the same across all the states and over time. There is no evidence to support such suppositions.
These intrinsic shortcomings severely limit what can be learned from the existing research, the report says. The committee recommended next steps for research that include collecting data that consider both capital and noncapital punishments for murder, conducting studies on how potential murderers perceive a range of punishments in homicide cases, and using statistical methods based on more credible assumptions about the effect of capital punishment on homicide rates.
The ultimate success of the research may depend on the specific questions being addressed, the report adds. Questions of interest include if and how the legal status or intensity of use of the death penalty affects homicide rates or whether executions affect these Rrates in the short term. The report acknowledged that new data and knowledge may not come quickly or easily, but such research may help to provide insight into the crime prevention effects of noncapital punishment that could be useful for future policy decisions.
The committee was not asked and did not investigate the moral arguments for or against capital punishment, the empirical evidence on whether capital punishment is administered in a nondiscriminatory and consistent fashion, or the cost of its administration.
The study was sponsored by Tides Foundation, the Proteus Action League, and the National Institute of Justice. The National Academy of Sciences, National Academy of Engineering, Institute of Medicine, and National Research Council make up the National Academies. They are private, nonprofit institutions that provide science, technology, and health policy advice under a congressional charter. The Research Council is the principal operating agency of the National Academy of Sciences and the National Academy of Engineering.
The members of the NRC review committee are listed on the release, as well as other information.
Prepublication information for Deterrence and the Death Penalty is also available.
Here'a roundup of the initial news coverage:
"Report: Deterrent effect of death penalty unclear," is the AP filing. It's also available from ABC News and CBS News.
A new report says there is no reliable research on whether the death penalty has any effect on the murder rate, more than 35 years since the Supreme Court allowed the resumption of executions in the United States.
The National Research Council report says all the studies on the possible deterrent effect of the death penalty suffer from fundamental flaws. The report identifies problems that include not taking account of the effects of alternatives to death sentences or insufficiently weighing how killers assess the risk of execution.
The authors of the new report say they are disappointed to reach the same conclusion as a 1978 study. They say their evaluation of the existing research does not favor either side in the long-running debate about deterrence and the death penalty.
"Does the Death Penalty Deter Crime? Studies are Inconclusive," at National Journal.
We still don’t know enough about whether the death penalty works to deter crime, and policymakers should ignore research that claims to say whether it does, the National Academy of Sciences said on Wednesday.
A panel of experts appointed by the independent, nonprofit academy reviewed more than 30 years of research done since the 1976 Supreme Court decision that reinstated the death penalty as constitutional.
“The studies have reached widely varying, even contradictory, conclusions. Some studies conclude that executions save large numbers of lives; others conclude that executions actually increase homicides; and still others conclude that executions have no effect on homicide rate,” according to the academy panel, chaired by Daniel Nagin, an expert in criminology and statistics at Carnegie Mellon University.
And:
The report turns up some interesting facts – for instance, only 15 percent of people who have been sentenced to death since 1976 have actually been executed.
"NRC: Death penalty effect research 'fundamentally flawed'," by Dan Vergano at USA Today.
Does the death penalty deter murderers? Criminology offers no answers, despite more than three decades of research, concludes an expert panel, reviewing studies of the deterrence effects of capital punishment.
In 1976, the Supreme Court reinstated the death penalty as the law of the land. Since then, 1,234 people have been executed in U.S. prisons, where 35 states apply the death penalty.
So, does it help lower the homicide rate? Who knows. Research looking into links between capital punishment and murder rates is "fundamentally flawed," concludes a National Research Council panel led by criminologist Daniel Nagin of Carnegie-Mellon University in Pittsburgh.
"One major deficiency in all the existing studies is that none specify the non-capital sanction components of the sanction regime for the punishment of homicide," says the panel's just-released report, such as life imprisonment. As well, "incomplete or implausible models of potential murderers' perceptions," confound the studies, making them suspect.
"We recognize this conclusion will be controversial to some, but nobody is well served by unfounded claims about the death penalty," Nagin said, in a telephone briefing for reporters. "Nothing is known about how potential murderers actually perceive their risk of punishment."
Related posts are in the deterrence category index.