Now let's talk about the deterrence issue. Deterrence is hard to measure, but there is certainly more evidence to show that the death penalty is not a deterrent. In fact, the conclusion should be pretty damn clear.
Dusting off the old criminal justice notes from college, the theory of deterrence posits that in order for any punishment to be an effective deterrent, the punishment must be swift, certain, AND severe. All three must be present. Of course, there is no perfect deterrent, partially due to our justice system (rights of the accused, due process, cruel and unusual punishment, etc). Swiftness dictates that you are quickly punished after the crime occurs, which almost never happens, and in fact it is rare to even be caught quickly after committing a crime. Certainty of punishment would mean that you are certainly going to get caught and punish if you commit the crime, but we all know that a large number of crimes, including murders, go unsolved. In terms of a severe punishment, it doesn't get any more severe than the DP, but without the other elements of swiftness and certainty, deterrence isn't going to happen. Then of course you can argue whether or not life in prison is on par with DP in terms of severity, or if it is a big enough difference to matter in terms of deterrence. I'd argue that life in prison without possibility of parole is pretty severe.
To reinforce this point, if the death penalty was an effective deterrent to committing murder, you might expect that the murder rates in states that use the death penalty would be lower than states that don't use capital punishment. Nope.
States that do not use the death penalty have significantly lower murder rates.
http://www.deathpena...er-murder-rates
This is not totally conclusive, you can argue correlation/causation or whatever else, but the people who really study this stuff agree:
Criminologists report that the death penalty does not deter murder
A recent study published in the Journal of Criminal Law and Criminology reported that 88% of the country’s top criminologists surveyed do not believe the death penalty acts as a deterrent to homicide. Eighty-seven percent of them think that the abolition of the death penalty would not have a significant effect on murder rates and 77% believe that “debates about the death penalty distract Congress and state legislatures from focusing on real solutions to crime problems.”
http://www.deathpena...d-death-penalty
There's also this l
ittle theory called the "Brutalization Effect," which suggests that executions actually lead to (or at least correlate with) an
increase in crimes:
Studies of capital punishment have consistently shown that homicide actually increases in the time period surrounding an execution. Social scientists refer to this as the "brutalization effect." Execution stimulates homicides in three ways: (1) executions desensitize the public to the immorality of killing, increasing the probability that some people will then decide to kill; (2) the state legitimizes the notion that vengeance for past misdeeds is acceptable; and (3) executions also have an imitation effect, where people actually follow the example set by the state, after all, people feel if the government can kill its enemies, so can they (Bowers and Pierce, 1980; King, 1978, Forst. 1983).
http://www.e-archive...ime_control.htm
That same article also says this about deterrence:
he scientific conclusion is clear. The death penalty does not deter homicide. No study has ever found a deterrent effect, no matter how skewed the research question was in favor the death penalty. It's alleged deterrent value is refuted by everything we know about violent crime. The death penalty, if it is to deter, must be a conscious part of a cost-benefit equation in the perpetrator's mind. There are very few murders that involve that level of rationality or consciousness of the outcomes. Most murders are (1) committed under the influence of drugs or alcohol; (2) committed by people with severe personality disorders; (3) committed during periods of extreme rage and anger; or (4) committed as a result of intense fear. None of these states of mind lend itself to the calm reflection required for a deterrent effect.
Finally, there is another kind of deterrence. I've been talking about general deterrence here, the idea that the notion of punishment will have a deterring effect on the general population. There is also specific deterrence, which means that when you punish someone, you deter that specific person from committing the same offense again. The death penalty is a damn effective form of specific deterrence; that person is not going to kill anyone else. But that same objective can be achieved with life in prison without parole.
So there you go. Feel free to provide an argument to show that the death penalty has any added benefit.
I got to use my CJ degree today!