"The death penalty debate does not interest me. Unlike other issues, I have a difficult time mustering any energy for the issue beyond linking the Church's teaching on the subject (which I'm too lazy to do, hence my point).
Intellectually I recognize what is at stake (human lives) and as such understand the importance of the topic. From a logical standpoint, the death penalty is more important than say, what tax hikes are coming down the pike."
Actually, my post for IGNITUM TODAY, plus the expanded footnote is the first post I've written concerning the death penalty in 8 years of blogging (and writing), as far as I know. And this was largely because I was writing in a symposium with the theme "mercy and killing," and was sure that the other bloggers would cover abortion and euthanasia quite thoroughly. The other post (and this one) are both in response to posts by Mr Blake which are directed to me. Concerning Mr Blake's post, I said it did a reasonably fair job of summarizing my position. There are essentially three conditions under which I think the death penalty is allowable.
- If it is the only just punishment for the crime committed.
- If it is the only way to defend innocent lives--Mr Blake called this "a sort of social self-defense: it should only be applied when safely locking someone up for the rest of his natural life is not a reasonable option."
- The argument can be made that it is justifiable as a deterrent to other violent criminals.
Note that this leaves open the question as to whether any or all of these three points can be applied to any class of crime or any particular crime. I think that 2 certainly can be applied in some cases: I can imagine some possible scenarios, though my imagining them doesn't mean that they are particularly frequent (or, for that matter, that they actually do happen). I also can think of some scenarios in which the death penalty seems to be a fitting punishment --1 is at least partially satisfied--though this does not mean that it is the only or the most just punishment for the crime. As for 3, it might work in a stand-alone sense as a deterrent, though it is worth asking how effective of a deterrent it is. I might go a step further by asking whether its deterrent effects are sufficient to justify its use; I lean towards "no," though if 1 or 2 is true for a given case, then the point is moot.
So, I think that the death penalty can at least in principle be just (1) or justifiable to the point where not carrying it out is unjustifiable (2). But this principle must be applied to individual cases, many of which will fail to satisfy the conditions necessary for carrying it out.
 And here's it's worth noting that the scale may not be one to which all can agree, at least not in details. For example, I consider a person who is a threat to souls to be a worse danger than one who is merely a threat to peoples' lives. Killing a person is not so bad as sending him to hell by poisoning his mind and his soul against God. The atheist or heretic who actually does work to so poison a man's soul might disagree. In some regimes, this claim that the soul is more important than the body is taken to the extreme of executing heretics, infidels, or atheists--all as defined as militating against the rulers' (or occasionally the popular) religion.
 Professors Edward Feser and Christopher Tollefson have had a bit of back-and-forth on this question recently, most of which is linked to here, with two later entries here (Tollefson) and here (Feser).