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Last week reporters, attorneys and state officials watched Oklahoma death row inmate Clayton Lockett writhe on the gurney as he was executed. It took nearly 45 minutes, and he eventually died of a heart attack after officials stopped the execution.
He’s not alone. Seven percent of all executions by lethal injection are "botched," or not done in line with protocol, according to an Amherst law professor. Each time, the death penalty debate reignites among legislators and the public about executions.
Sen. Tom Coburn, R-Okla., went on MSNBC’s Morning Joe May 1 to emphasize his support for the death penalty, despite the complication with Lockett’s execution.
"I think it is a deterrent that does affect and impact people," he said. "I’ve given a lot of thought. I don’t like it. I wish we put everybody that had such a history as this gentleman behind bars and working and doing things that would help them, but I haven’t changed my position."
We decided to check the research to see if Coburn was right that the death penalty is a deterrent. Does the death penalty discourage crime?
We found there’s no conclusive evidence to support any viewpoint, including Coburn's. We can’t definitively say that the death penalty deters homicides, increases homicides or has no effect, so Coburn can't back up his point with widelyaccepted scientific evidence.
Daniel Nagin, a public policy professor at Carnegie Mellon University, chaired the National Academy of Sciences Committee on Deterrence and the Death Penalty. He and his team were tasked with addressing whether or not available studies can prove that the death penalty serves as a deterrent for violent crime.
In 2012, he and his team published "Deterrence and the death penalty," a report that sums up more than three decades worth of research:
"The committee concludes that the research to date on the effect of capital punishment on homicide is not informative about whether capital punishment decreases, increases, or has no effect on homicide rates. Therefore, the committee recommends that these studies not be used to inform deliberations requiring judgments about the effect of the death penalty on homicide. Consequently, claims that research demonstrates that capital punishment decreases or increases the homicide rate should not influence policy decisions about capital punishment."
Nagin found a few common problems with the existing research:
No comparison to deterrent effects of life imprisonment: Study authors often can’t access the data they need from the government. An ideal deterrence study would examine whether people are more deterred by the death penalty than by other serious punishments.
No information on would-be murderers’ perceptions: "Deterrence is about how people are responding to their perceptions," Nagin said. Are potential criminals considering their chances of ending up on death row before they commit violent crimes? We don’t know.
Statistical flaws: Nagin’s committee determined that the research was so flawed, it couldn’t be informative.
However, Nagin said research does show that punishment for crime, in general, is a deterrent.
"It’s the certainty of apprehension, not the severity of the ensuing consequences, that is the more effective deterrent," he said.
The Death Penalty Information Center, The Sentencing Project and other death penalty experts we contacted pointed to Nagin’s report as the most authoritative literature on death penalty deterrence, but there are a significant number of people in the field who side with the studies Nagin and others have criticized.
Coburn’s office pointed us toward a 2007 Fox News column by John Lott, founder of the Crime Prevention Research Center. Lott defended a group of studies that found that every execution saves 15 to 18 potential murder victims. They’ve been widely criticized for the way they count homicides, mistakes in methodology and making conclusions based on the very small pool of U.S. executions.
It could be quite some time before studies produce a widely respected answer to the deterrence question.
"The road forward is not easy," Nagin said.
Coburn said, "I think (the death penalty) is a deterrent that does affect and impact people." Overall, many experts say the existing research has limitations and doesn’t clearly show support for or against the death penalty as a deterrent. So Coburn can't prove his viewpoint is correct. However, executions, along with prison sentences and other punishments for crime, do generally deter criminals.
We rate Coburn’s claim Mostly False.
Amnesty International, "The death penalty and deterrence," accessed May 1, 2014
Criminal Justice Legal Foundation, "Tally of death penalty deterrence studies from 1996 to 2010," accessed May 1, 2014
Denver Post, "No credible evidence on whether death penalty deters, experts say," June 3, 2013
Email interview with Anne Holsinger, Death Penalty Information Center specialist, May 5, 2014
Email interview with Frank Zimring, University of California Berkeley criminal justice law professor, May 3, 2014
Email interview with James Acker, University at Albany criminal justice professor, May 1, 2014
Email interview with John Hart, Tom Coburn spokesman, May 5, 2014
Email interview with John Lott, Crime Prevention Research Center founder, May 4, 2014
Email interview with Josh Marquis, Astoria, Ore., district attorney, May 1, 2014
Email interview with Kent Scheidegger, Criminal Justice Legal Foundation, May 1, 2014
Email interview with Mark Mauer, The Sentencing Project executive director, May 2, 2014
Fox News, "John Lott: Death as deterrent," June 20, 2007
Journal of Criminal Law and Criminology, "Deterrence and the death penalty: the views of experts," Fall 1996
Journalist’s Resource, "The research on capital punishment: recent scholarship and unresolved questions," May 1, 2014
MSNBC Morning Joe, "Coburn: I see the death penalty as a deterrent," May 1, 2014
National Research Council, "Deterrence and the death penalty," 2012
Phone interview with Daniel Nagin, Carnegie Mellon University public policy professor, May 5, 2014
PolitiFact, "Thompson ignores contrary death penalty research," Aug. 21, 2007
Stanford Law Review, "Uses and abuses of empirical evidence in the death penalty debate," Jan. 9, 2006
Vox, "Botched executions have been around as long as the death penalty," May 1, 2014
Washington Post, "Studies say death penalty deters crime," June 11, 2007
Washington Post, "There’s still no evidence that execution deters criminals," April 30, 2014
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