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Crime & Law Enforcement Issues & Death Penalty/National Academy of Sciences and the Death Penalty


QUESTION: Does the 2012 report by the National Academy of Sciences change your mind about the deterrent effects of the Death Penalty(1)?



Based upon your question, as well as your previous inquiries, I am not sure that you have

1) read the study, yourself or

2) Understood the study, if you have read it.

Your forwarding link only sent me to the News Release.

The full study is here:

Have you read it?

I would like to start there, simply because you are such a negative person, who complains with little knowledge.

I suspect you haven't read the study or understood it, for if you had, you would not have made the inquiry that you did.

Your inquiries to me are only based upon negative attacks, instead of a search for knowledge and understanding.

Have you matured since your last inquiries? I hope so.


As you appear not to know, the NAS study does not undercut the reality of death penalty deterrence, but it is only critical of a few of the 28 studies finding for deterrence.

No one is saying that deterrence doesn't exist. They can't.

We all know that every prospect of a negative outcome deters some. It is a truism.

The question is not  "Does the death penalty deter?" - Of course it does, just as all sanctions do.

The relevant question is - "How much does the death penalty deter?"  - a question that will never be answered to anyone's satisfaction or agreeement.

Even based upon the recent 28 studies finding for deterrence, which found from 1-28 innocent lives saved per execution, not even those can agree on the numbers.


If you have read the NAS paper and tried to understand it, I will respond.  Have you?

[an error occurred while processing this directive]---------- FOLLOW-UP ----------

QUESTION: Mr. Sharp,

I did read the NAS report and it does make me temper my opinion. I know that research on the brutalization effect, for example, is limited. I thank you because you have made me work to find out more about Death Penalty research and the limitations of econometric research methods.   

From what I gather, the report says that it cannot be determined at this point that the Death Penalty deters any future net murders, especially when a life without sentence may be imposed. It also discusses the "fundamental" flaws in the research that you often quote. The committee members include the late James Q. Wilson, who I would identify as a conservative scholar.  

Just because you call the deterrence  effect "a truism" does not make it true in perpetuity as conditions change. For example, I didn't see any mention of lethal injection as a deterrent (as Zimmerman's study discusses), which would further complicate the argument, given that lethal injection has become the mode of almost all US executions.   

From the report:

"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.

I just found this follow up.

I am not sure you understood the NAS review (hereinafter Nagin et al as "Nagin").

It's been a while since I've read it, . . .

The Nagin review did mention Shepherd's brutalization study, but failed to mention that the study further enhanced the findings for a deterrent effect, which seemed a glaring omission by Nagin, given the subject of the Nagin review.

No, Dahn, what the Nagin review found was that, in their opinion, which is contradicted by the opinions of the authors of those studies, was that Nagin couldn't determine if there was or was not deterrence based upon those studies.

The deterrent effect is always true in perpetuity because all prospects of a negative outcome deter some. It is a truism, forever.

Your confusion is that we are not speaking of that truism. We are speaking about specific studies and whether the Nagin review is more credible that the original studies which Nagin reviewed.

If a study does not find for deterrence or is undecided, that does not have any influence on whether or not it is a truism that all prospects of a negative outcome deter some. That truism remains, in perpetuity.

Zimmerman's study is one of 27 studies since 2000 finding for deterrence. Zimmerman's one study does not do away with the other 27 studies which found for deterrence via lethal injection. Had you read the studies you would know that they are, in total, very broad in their findings and no two of them, exactly, agree with one another.

I suspect that Zimmerman would tell you that his one study does not negate the findings of the other 27 studies. Ask him. Also ask him if incentives, either positive or negative, will always effect behavior.

On that point, his answer will be yes, because it is a truism, in perpetuity. I think Nagin would answer yes, as well. Ask him.

It is of interest that Nagin wrote: "Fundamental flaws in the research we reviewed make it of no use in answering the question of whether the death penalty affects homicide rates,".

He is speaking of the specific research, that he finds flawed, a finding, it appears, not shared by those he is critical of, who, I suspect, still stand by their own research, as I have seen no agreement from them with Nagin.

"Nagin's "homicide rate" point may be confusion or semantics. Homicide and other crime rates could all stay the same, every year, but there still would be a deterrent effect. Let's say that 1000 murders and other crimes were deterred each year by sanctions, but that there were also a thousand more murders and other crimes. Deterrence would still exist but murder and crime rates would be the same.

Whether crime/murder rates are high or low, whether rising, falling or staying the same, some criminals/potential criminals are deterred by sanctions.

Nagin does not and cannot say that the death penalty does not deter. Nagin only says that he finds the research, in the subject studies, to be flawed to the point Nagin finds them unreliable to make any determination, whether to deterrence or non deterrence.

I am unaware that the Nagin review has effected the confidence in their studies of any of the authors of the studies which Nagin reviewed.

Dahn, you wrote, "none of the research that has been done accounted for the possible effect of noncapital punishments on homicide rates."

I think you took that or paraphrased it from the Nagin review.

It is odd, because the only way that any of the other researchers could determine the deterrence effect of the death penalty was by having other sanctions as either a constant or a variable within their studies, so as to measure the effect of the death penalty. That is what they did. I am not sure how you or Nagin could have missed that obvious issue.

Dahn writes: "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."

It is obvious where their perceived risk comes from, it comes from what I call the marketplace - the same locations as for all of us - the media, when we learn of death penalty laws, death sentences and executions and/or from conversations or study. The perceived risk is individual and will be higher or lower for all individuals, as with all things in life and for all people. That you or Nagin are unaware of that is, simply, more than a bit odd.

One of the glaring perceptions of the Nagin review is this:

The Chair of this study is Daniel Nagin, the Teresa and H. John Heinz III University Professor of Public Policy and Statistics, Carnegie Mellon University, since January, 2006 (2)

Nagin's income is financed by a liberal anti death penalty foundation (3).

The conflict of interest could not be more obvious or severe.

Two of the three funding groups for this study are:

Tides Foundation and the Proteus Action League, with Tides getting major funding from Heinz (4).

Both are huge grant providers for the anti death penalty movement (4).

The conflict of interest could not be more obvious or severe.

It think it impossible for those financing groups to have been involved if they thought there was any chance of the study concurring with a deterrent effect.

I am astounded that NAS would allow this under their banner.

Why were these obvious conflicts not disclosed? Why were they allowed, at all?

I am unaware if any of the 28 studies finding for deterrence, or their authors, were funded by pro death penalty groups.





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Dudley Sharp


Any question specific to the death penalty.


Mr. Sharp has appeared on ABC, CBS, CNN, FOX, NBC, NPR, PBS, BBC and many other TV and radio networks, on such programs as Nightline, The News Hour with Jim Lehrer, The O'Reilly Factor, Oprah, etc., has been quoted in newspapers throughout the world and is a published author. A former opponent of capital punishment, he has written and granted interviews about, testified on and debated the subject of the death penalty, extensively and internationally. Partial List: --- Guest Lecturer, US Department of State, Senior Seminar, National Foreign Affairs Training Center, Washington DC, March 30, 1999 ---"Equal Treatment and the Death Penalty: A Conference"; Participant, John Jay College of Criminal Justice, City University of New York, November 11, 2002 --- Participant, The Governor's (Illinois) Commission on Capital Punishment. I was asked to present a paper on deterrence and the death penalty. I presented two papers -- one on deterrence and one on innocence issues. 2001 --- "Rethinking the Death Penalty", Nightline, ABCNews, 6/22/00. Interesting discussion with former Florida Supreme Court Justice Kogan, who somehow confused the concept of alleged innocent death row inmates released on appeal with innocent death row inmates executed. ---- "The Death Penalty", This Week with Sam Donaldson and Cokie Roberts, ABC News, 6/4/00 Appearance with Illinois Governor George Ryan, discussing moratoriums and innocence issues. --- "Death Penalty Update", The News Hour with Jim Lehrer, 7/30/00 PBS. A review of death penalty issues. --- "Do We Need the Death Penalty? Yes", an essay, The World and I Magazine, September 2002, at continued below

Mr. Sharp is, now, an independent, non affiliated activist Prior to that time, he was Vice President, Political Director, Chairman of the Endorsement Committee and member of the Board of Directors of Justice For All from July 1993, when JFA was founded, through January 2000. He was Resource Director for JFA through 2003. Justice For All is a criminal justice reform organization based in Houston, Texas. In those positions, he was an active participant in every major issue undertaken by JFA, including policy direction, lobbying, victim's assistance and public presentations. He created the process for endorsing political candidates, forming a political endorsement committee, investigating the background of candidates, developing a questionnaire used to explore the candidates true positions on criminal justice and victim's issues resulting, finally, in a committee recommendation for endorsements. He is a death penalty expert who was opposed capital punishment until December 1995. Tulane U., BA Philosophy 1978

1) Newspapers around the world 2) "Death Penalty Debate", between Eric Zorn, an anti-death penalty columnist with the Chicago Tribune, and Dudley Sharp. April-June, 2000. Visits many of today's major death penalty issues in an in-depth format and is an illustration that assumption, not fact, often guide reporting on this issue. 3) Blogs/websites a) ProDPinNC B) c) Chapters in Books "The Mentally Retarded do not Face Execution", Is The Death Penalty Fair?, Greenhaven Press, Mary Williams editor, 2003 "Innocent People Have Not Been Executed", from Problems of Death, Opposing Viewpoints Series, Greenhaven Press, 2000 "The Death Penalty Should Be Retained", from Capital Punishment, Current Controversies, Greenhaven Press, 2000 "The Death Penalty is Just", Dudley Sharp, p 17-15, also pages 11 & 62, The Death Penalty, Opposing Viewpoints, Thompsaon/Gale 2006 "The Death Penalty", pg 26,31,33, 39, 79, Current Issues, Reference Point Press, 2012

continued --- "The Death Penalty", Speaker, Annual meeting of the American Corrections Association, San Antonio, Texas, 1997. Debate between myself and Richard Burr, a well known death penalty defense attorney and anti death penalty activist. --- "Capital punishment is an effective way to protect innocent people", May 27, 2000 - St. Louis Post Dispatch. Many more innocents will be put at risk by not executing. Scroll down about halfway to reach the letter --- "Death on Hold?", Fort Worth Star Telegram, 2/5/00. Why a moratorium on executions is unwarranted. --- "Bias on the death penalty", Richmond Times Dispatch, 4/23/01, deals with the racial issues. --- "Washington Journal", C-SPAN, 4/19/01. Death penalty moratorium issues, with Jane Henderson of the Quixote Center in Maryland, coordinator of the Equal Justice Project. A great show to view virtually all the false and misleading information put forward by the anti-death penalty movement. ---, Taking Sides, essay "Exoneration Hype Exaggerated", 5/10/00. A brief essay regarding the absence of journalistic standards when dealing with issues of innocence and the death penalty. It is the second article down. --- "ABA's Proposed Moratorium Relies on Flimsy Facts", The Texas Lawyer, March 16, 1997. An article showing how inaccurate and misleading the American Bar Association was in their foundation in asking for a moratorium on executions. --- "Guilty as Charged", Wall Street Journal, A22, 6/28/00. Co-authored with Dianne Clements, an article about the highly publicized case of executed Texas murderer Gary Graham.

Past/Present Clients
--- Testimony before the Pennsylvania State Senate Judiciary Committee, February 2000. Death Penalty Moratorium legislation -- Alaska Senate Judiciary Committee, Death Penalty Testimony, July 1997. Testimony regarding referendum on the death penalty and other death penalty issues --- Texas Legislature, testimony in both House and Senate regarding death penalty issues and bills.

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