Capital punishment and deterrence: what the research shows

This post has a twin post which talks about the evidence against capital punishment from the Bible.

Why do people support the death penalty? Because research conducted by multiple teams of scholars at multiple universities have shown that capital punishment deters crime.


“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).

And specifically:

• 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 case anyone is wondering what sort of crimes are deterred by the death penalty, you can read this graphic description of a recent death-penalty crime.

What sort of crimes are eligible for the death penalty?

Here’s an example of a dealth-penalty eligible crime from the Hartford Courant. (WARNING: graphic!)


A Superior Court jury today sentenced Steven Hayes to death for the murders of Jennifer Hawke-Petit and her daughters, Hayley and Michaela, during a seven-hour home invasion, robbery and arson at their Cheshire home in July 2007.

Outside the courthouse after the verdicts, Hawke-Petit’s father, the Rev. Richard Hawke, said “There are some people who do not deserve to live in God’s world.”

Asked what he had in his heart, Dr. William Petit Jr. struggled with his answer. “….Probably many of you have kids,” he said, pausing to choke back tears. “Michaela was an 11-year-old little girl…tortured and killed in her own bedroom, surrounded by her stuffed animals….”

Petit then talked about his daughter Hayley’s bright future and her strength and the children that his wife, Jennifer, helped.

“So, I was really thinking of the tremendous loss” during the verdict, Petit said, adding that he was pleased with it, but “mostly I was sad for the loss we have all suffered.”

Asked if he thought there’d be closure now, Petit said, “There’s never closure. There’s a hole…. with jagged edges…that may smooth out with time, but the hole in your heart and the hole in your soul” remains.

“This isn’t about revenge,” Petit said. “Vengeance belongs to the Lord. This is about justice.”

[…]The jury sentenced Hayes to death on six counts: killing Hawke-Petit and Michaela and Hayley in the course of a single action; killing a child under the age of 16; killing Hawke-Petit in the course of a kidnapping; killing Hayley in the course of a kidnapping; killing Michaela in the course of a kidnapping; and killing Hawke-Petit in the course of a sexual assault.

[…]Hayes, 47, of Winsted, was convicted Oct. 5 of breaking into the Petit home, beating Petit, tying up and torturing the family as Hayes and another man ransacked the home for cash and valuables and tortured the family for seven hours. Testimony during Hayes’ trial showed that at one point in the break-in, Hayes forced Hawke-Petit to go to the bank to withdraw money. During that time, according to testimony, Komisarjevsky sexually assaulted Michaela Petit, 11.

When Hawke-Petit and Hayes returned from the bank, Hayes raped and strangled Hawke-Petit. The house was doused with gasoline and set on fire as the intruders fled, testimony showed. Hayley, 17, and Michaela died of smoke inhalation.

[…]Prosecutors used the words of Hayes’ younger brother Matthew to counter testimony that home-invasion crime was an aberration in Hayes otherwise troubled but basically nonviolent life.

Matthew Hayes portrayed his brother as a conniving, sadistic, violent thief who saw Matthew take countless beatings from his brutal father for Steven Hayes’ misdeeds. At one point, Steven Hayes held a gun to Matthew’s head, according to the statement, which was given to state police after the home invasion.

Examples of Hayes’ sadistic behavior toward his brother included hooking Matthew to the garage door by his belt and raising the door up and down, and holding Matthew’s hand to a red-hot burner. Matthew said his brother’s life of crime was not a result of bad parenting or poor childhood. He said Hayes never learned to take responsibility for his actions.

Sometimes, I think that we have stopped judging others because we do not want to be judged ourselves. We hope that by not judging anyone, that we will somehow escape being judged by anyone – especially by God himself. The opposition to punishing the guilty is, I think, really just a way of expressing our desire to do away with punishment entirely. We would rather have the freedom to sin with impunity than to protect the victims of sinfulness from harm. We want to escape responsibility for anything we do that harms others.

Dennis Prager has a neat expression from Rabbinical literature that describes the problem with people who are anti-death-penalty: “those who are kind to the cruel, will be cruel to the kind”.

I actually consider the death penalty to be an important test of whether a person is a Christian or not, because it shows what they think about the serious of moral crimes, and whether they accept what research says, and what the Bible says, instead of valuing peer approval more than justice. It tells you how seriously a person feels about their own sinfulness. Death penalty supporters don’t view sinners as victims – they view victims as victims, and they believe that evil people need to be punished. It’s hard for me to see how someone can claim to be a Christian and oppose justice.

15 thoughts on “Capital punishment and deterrence: what the research shows”

  1. I am for the death penalty in principle.

    In practice, I’m a bit more circumspect. I worry about miscarriages of justice.


    1. Yes. I live in TX, and the number of death penalty convictions that have been overturned by new evidence in the South lately has been more than a little disturbing. I have seen how a human justice system can and will railroad people.


  2. I am a CT resident, and I remember when these murders happened. As more and more details come out, I am more and more horrified at what these two men were capable of doing.

    It sickens me that I live in a state that has at its disposal capital punishment, but refuses to use it. The last person executed was on death row for more than 20 years, and I believe the legislature (deep blue of course) and the Governor oppose the practice. So Hayes, and soon Kamisarjevsky will effectively receive a life sentence.


  3. Wow, this takes the force out of the liberal argument that death penalty is not a deterrent for heinous crime…thank you Wintery Knight.


    1. I want all my readers to go out there, armed with facts, and have fun with your Christian faith. Crush your enemies in debate and revel in their pitiable whimpers of dismay!

      (shakes mailed fist)


  4. I’ve never really concerned myself with the deterrence angle. Capital punishment was always about justice for the victims to me. At the same time, it is plain that the murderer is clearly deterred from ever murdering again.


  5. Here’s something Jonah Goldberg said with which I agree: “I do believe there’s a deterrence effect from the death penalty. But I don’t think that’s anything more than an ancillary benefit of capital punishment. It’s unjust to kill a person simply to send a message to other people who’ve yet to commit a crime. It is just to execute a person who deserves to be executed.”


  6. For Fred and everyone else who’s having a problem with Capital Punishment:

    I think that the strongest argument in this piece is the when you use the line from the Talmud “those who are kind to the cruel, will be cruel to the kind” (rough translation of Qohelet Raba, 7:16). It speaks to the Judeo-Christian history that is the defense of this type of justice.

    The confusion for most people, I think lies in the right to life. What the Talmud then hints at is the fact that, when we lose sight of what is objectively good and bad and reward bad behaviour, we set ourselves up for the backlash that comes from not standing on principle and not supporting objective truths. An example of this was Wintery Knight’s post on Iran prepares to execute evangelical Christian pastor for apostasy . My comment on that post was, “When you give away your own rights freely, the price you pay is costly.” The fact that Christian nations are pacifist puts Christians in jeopardy the world over, not just at home. Christians lose their negative right not to be killed, a problem that Muslim people do not face in any Western country right now, primarily out of fear of retaliation. But where does one person’s rights stop and another person’s begin? Can we make value judgments?

    Most certainly, justice is all about value judgments and the law must be preserved. In 1840, Frederic Bastiat, the French economist and journalist, wrote about how democracy had perverted the law and he dubbed the law as it was in France at the time ‘legal plunder’ stating that instead of preserving rights the law was being used to preserve only a certain groups rights at the expense of another and to the benefit of the state. Here we have the same problem. Politicians who buy votes on their compassionate stances (preserving the rights of murderers), while true law and order flies out the window.

    It’s sad how people who advocate for the death penalty are accused of “playing God,” when Bastiat points out that it is the socialist who “plays God” and tries to re-shape the world to the way they think it should be. “The law guilty of that very iniquity which it was its mission to punish!”

    Bastiat explained that although God gives us life it is our job to use our “faculties” in our existence to assimilate. “Existence, faculties, assimilation—in other words, personality, liberty, property—this is man…it is because personality, liberty, and property exist beforehand, that men make laws.”

    Bastiat describes law as”the collective organization of the individual right to lawful defense.” and more specifically he says, “it is the substitution of collective for individual forces, for the purpose of acting in the sphere in which they have a right to act, of doing what they have a right to do, to secure persons, liberties and properties, and to maintain each in its right, so as to cause justice to reign over all.” This is why Capital Punishment exists under the law, as one of the ways society collectively defends itself. According to Bastiat, “Law is organized Justice,” Being a conservative, pro-capital punishment and for the right to bear arms are three qualities that must be present in a Christian, especially one that abides by the rule of law. Bastiat warns us that if we seek to change that law we pervert it.

    In a letter to Bastiat, de Lamartine stated, “Your doctrine is only half of my program; you have stopped at liberty, I go on to fraternity,” to which Bastiat answered, “The second part of your program will destroy the first.” Fraternity, compassion, forgiveness, are all voluntary and have no place being under the control of the law. Man can forgive, man can introduce positive actions into his life that affect his neighbour, but the law cannot force a man do to anything because it exists to enforce negative rights, The law can only oblige someone to abstain from harming his neighbour. When the law is infringed upon justice must be enforced, because injustice arises from the absence of justice and vice-versa.

    If you want to understand the function of law in society click on one of the books Wintery Knight has recommended above and when you get to Amazon order a copy of The Law by Frederic Bastiat, it’s an easy read and as a bonus if you go through this page you’ll also be supporting this blog!


      1. Am I supposed to give you the link that I reference your links at? I see that lots of people do that when they re-blog, but I am using your links inside of apologetic discussions and responses on other websites. I didn’t know if that is different? (Thanks for making my life easy with all of your hard work! It’s almost like “blog re-distribution” from a dedicated 1%-er [you] to a lazy person [me]. :-))

        I want to be up-and-up on this, because I remember the long-gone days when I was an academic and had to be careful citing sources. Cuz, frankly, I am stealing your stuff left-and-right :-), but always just as a direct link to you, not claiming I wrote it, or cutting-and-pasting your blogs, or anything devious like that. I just say things like “here is a link with scholarly results that offer another view….”

        I have come to the conclusion that I don’t have to make a lot of independent arguments when you have already done all of the heavy lifting. But, I am very careful to not include your links out of context, IMO. Thanks for your advice!

        Oh, plus, it helps me in witnessing situations when someone goes off on a hot button topic. I can merely reply “have you studied this issue? Would you like a scholarly analysis?” Then, I can link to you or STR or a few others.

        I guess Nate might say that I’m linking to death, but I always make an assertion, premise, conclusion, etc before linking to you. That way if they don’t have time to check out the link, they will at least know that I have at least attempted to support my assertion and / or logic. Hope this makes sense.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s