Death Penalty
See other issues.
We believe that the death penalty is an important tool of society that has been made too costly.
Killing Innocents
A common argument against the death penalty, is to point out that it is not technically possible to avoid killing innocents on occasion.
Ironically enough, abortion, which guarantees the murder of innocents, has been credited with reduced crime rates in New York, and many think this makes abortion a good thing. Belief in the goodness of abortion, however, correlates strongly with belief in the badness of the death penalty, often attacked for its killing of innocents.
We consider abortion to be a form of murder, but consider it *potentially* justifiable under a very narrow set of circumstances, namely threat to the life of the mother, threat to the life of the child, or when the pregnancy was a result of rape. So, I would occasionally condone the killing of innocents, sad as it might be.
Similarly, in war, there is a risk of killing "innocents" (non-enemies), but the risk of killing innocents does not lead me to conclude that my country needs to abandon defense of its citizens. (Though, war is, often enough abused.)
If I was to use a gun to defend myself from an attacker, I might accidentally hurt myself, or someone else. Do I then abandon that self defense.
Similarly, in each circumstance where we might consider applying the death penalty, there is some risk of killing innocents. The death penalty, however, is a form of domestic self-defense (or, at least, it should be thought of that way), and while the opportunity for reflection should be embraced, so as to come to a thoughtful determination of the best course of action, the fact remains that we are weighing very real risks and costs against the risk of killing an innocent, and just like in other scenarios, that risk, and that cost, is not so great as to justify paralysis.
Killing to Show Killing is Wrong
It is possible that capital punishment has some deterrent affect, but that should not be a significant concern. The "tough on crime" viewpoint has been shown to do little more to deter crime than sentences and policies of a softer nature. It has lead to high recidivism rates and cruelty.
We don't (or at least shouldn't) kill people who kill people to teach anybody that killing is wrong. Killing people, in fact, isn't always wrong, so that would be a stupid idea to teach.
Killing is necessary to sustain life. Death is a natural part of the human experience. We kill people who are "murderers", because they pose an unacceptable risk and burden to society by demonstrating a willingness to violate the right to life of others without reasonable cause. (eg. Self-defense, defense of property, defense of country, defense of neighbor, ...)