Not what I am reading.
http://www.deathpenaltyinfo.org/deterrence-states-without-death-penalty-have-had-consistently-lower-murder-rates
This obfuscates a great deal. States with death penalties may have higher murder rates regardless. According to the data in your link, you could argue that repealing the death penalty reduces murder rates, which I think is an absurd argument to make.
From your link, we see that the murder rate in some states with the death penalty is lower than in some states without the death penalty:
So we see it is all "over the map."
What likely happens in many places with high murder rates is that the death penalty is either kept or introduced because of the disgust of citizens with the higher murder rates.
Here is the other side of the deterrent argument:
Death penalty is a deterrent
George E. Pataki, Governor of New York State
USA Today - March 1997Capital punishment gives killers good cause to fear arrest and conviction.
Upon taking office, I immediately began the process of reinstating the death penalty. Two months later, I signed the death penalty into law for the most heinous and ruthless killers in our society.....
Since I took office in 1995, violent crime has dropped 23, assaults are down 22, and murders have dropped by nearly one-third. New Yorkers now live in safer communities because we finally have begun to create a climate that protects and empowers our citizens, while giving criminals good cause to fear arrest and conviction. I believe this has occurred in part because of the strong signal that the death penalty and our other tough new laws sent to violent criminals and murderers: You will be punished with the full force of the law....
http://findarticles.com/p/articles/mi_m1272/is_n2622_v125/ai_19217186/
Ernest van den Haag, a Professor of Jurisprudence at Fordham University who has studied the question of deterrence closely, wrote: "Even though statistical demonstrations are not conclusive, and perhaps cannot be, capital punishment is likely to deter more than other punishments because people fear death more than anything else. They fear most death deliberately inflicted by law and scheduled by the courts. Whatever people fear most is likely to deter most. Hence, the threat of the death penalty may deter some murderers who otherwise might not have been deterred. And surely the death penalty is the only penalty that could deter prisoners already serving a life sentence and tempted to kill a guard, or offenders about to be arrested and facing a life sentence. Perhaps they will not be deterred. But they would certainly not be deterred by anything else. We owe all the protection we can give to law enforcers exposed to special risks."
Justice Stewart held in the Supreme Court in Gregg v. Georgia:
Although some of the studies suggest that the death penalty may not function as a significantly greater deterrent than lesser penalties, there is no convincing empirical evidence supporting or refuting this view.
We may nevertheless assume safely there are murders, such as those who act in passion, for whom the threat of death has little or no deterrent effect. But for many others, the death penalty undoubtedly, is a significant deterrent.
There are carefully contemplated murders, such as murder for hire, where the possible penalty of death may well enter the cold calculus that precedes the decision to act. ( as cited in Carrington, 1978. p. 87).
http://deathpenaltycurriculum.org/student/c/about/arguments/argument1a.htm
Study says Texas death penalty a homicide deterrent
HUNTSVILLE — As many as 60 people may be alive today in Texas because two dozen convicted killers were executed last year in the nation's most active capital punishment state, according to a study of death penalty deterrence by researchers from Sam Houston State University and Duke University.
A review of executions and homicides in Texas by criminologist Raymond Teske at Sam Houston in Huntsville and Duke sociologists Kenneth Land and Hui Zheng concludes a monthly decline of between 0.5 to 2.5 homicides in Texas follows each execution.
“Evidence exists of modest, short-term reductions in the numbers of homicides in Texas in the month of or after executions,” the study published in a recent issue of Criminology, a journal of the American Society of Criminology, said.
The study adds to decades of academic dissection of the death penalty and deterrence. Results over the years vary from capital punishment saving more lives than suggested in this study to no conclusive effect.
http://www.chron.com/disp/story.mpl/metropolitan/6802314.html
...a series of academic studies over the last half-dozen years that claim to settle a once hotly debated argument—whether the death penalty acts as a deterrent to murder. The analyses say yes. They count between three and 18 lives that would be saved by the execution of each convicted killer.
The reports have horrified death penalty opponents and several scientists, who vigorously question the data and its implications.
So far, the studies have had little impact on public policy. New Jersey's commission on the death penalty this year dismissed the body of knowledge on deterrence as "inconclusive."
But the ferocious argument in academic circles could eventually spread to a wider audience, as it has in the past.
"Science does really draw a conclusion. It did. There is no question about it," said Naci Mocan, an economics professor at the University of Colorado at Denver. "The conclusion is there is a deterrent effect."
A 2003 study he co-authored, and a 2006 study that re-examined the data, found that each execution results in five fewer homicides, and commuting a death sentence means five more homicides. "The results are robust, they don't really go away," he said. "I oppose the death penalty. But my results show that the death penalty (deters)—what am I going to do, hide them?"
Statistical studies like his are among a dozen papers since 2001 that capital punishment has deterrent effects. They all explore the same basic theory—if the cost of something (be it the purchase of an apple or the act of killing someone) becomes too high, people will change their behavior (forego apples or shy from murder).
To explore the question, they look at executions and homicides, by year and by state or county, trying to tease out the impact of the death penalty on homicides by accounting for other factors, such as unemployment data and per capita income, the probabilities of arrest and conviction, and more.
Among the conclusions:
_ Each execution deters an average of 18 murders, according to a 2003 nationwide study by professors at Emory University. (Other studies have estimated the deterred murders per execution at three, five and 14).
_ The Illinois moratorium on executions in 2000 led to 150 additional homicides over four years following, according to a 2006 study by professors at the University of Houston.
_ Speeding up executions would strengthen the deterrent effect. For every 2.75 years cut from time spent on death row, one murder would be prevented, according to a 2004 study by an Emory University professor.
In 2005, there were 16,692 cases of murder and nonnegligent manslaughter nationally. There were 60 executions.
The studies' conclusions drew a philosophical response from a well- known liberal law professor, University of Chicago's Cass Sunstein. A critic of the death penalty, in 2005 he co-authored a paper titled "Is capital punishment morally required?"
"If it's the case that executing murderers prevents the execution of innocents by murderers, then the moral evaluation is not simple," he told The Associated Press. "Abolitionists or others, like me, who are skeptical about the death penalty haven't given adequate consideration to the possibility that innocent life is saved by the death penalty."
http://www.washingtonpost.com/wp-dyn/content/article/2007/06/11/AR2007061100406.html
A November 18, 2007 New York Times article [23] reported the following information:
- One reason that there is no consensus on whether or not the death penalty is a deterrent is that it is used so rarely - only about one out of every 300 murders actually results in an execution. In 2005 in the Stanford Law Review, 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 that 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... The existing evidence for deterrence... is surprisingly fragile." Wolfers stated, "If I was allowed 1,000 executions and 1,000 exonerations, and I was allowed to do it in a random, focused way, I could probably give you an answer."
- Naci Mocan, an economist at Louisiana State University, authored a study that looked at all 3,054 U.S. counties over two decades, and concluded that each execution saved five lives. Mocan stated, "I personally am opposed to the death penalty... But my research shows that there is a deterrent effect."
- Joanna M. Shepherd, a law professor at Emory with a doctorate in economics who was involved in several studies on the death penalty, stated, "I am definitely against the death penalty on lots of different grounds... But I do believe that people respond to incentives." Shepherd found that the death penalty had a deterrent effect only in those states that executed at least nine people between 1977 and 1996. In the Michigan Law Review in 2005, Shepherd wrote, "Deterrence cannot be achieved with a half-hearted execution program."
http://en.wikipedia.org/wiki/Capital_punishment_debate#Deterrence
This data makes me have to rethink my opposition to the death penalty.
BTS