Kathryn, I know what you mean when you say that such a report makes you uneasy. I share that reaction; simultaneously, however, I have another reaction, which is that the alternatives you prefer would not seem commensurate to the crime. I suppose it is because I have both of these reactions that I have no firm position on the death penalty.
It is certainly true that the state could deal retribution to a person such as John Allen Muhammad without killing him. After I wrote my original post, I asked myself: “Why do you think that there is no other meet form of retribution in this case?” I had written that the murders were “particularly cold-blooded”—but why is that the relevant consideration? Upon reflection, I concluded that it is a question of symmetry: A man calculatingly executes innocent persons, so the state calculatingly executes him. (As opposed to: The state calculatingly executes a man for a murder committed without forethought in a moment of passion.)
I think it is hard to separate the idea of just retribution from a kind of eye-for-eye, tooth-for-tooth approach. It is unseemly to say that this is what one advocates, and indeed I do not advocate it in any absolute way; but I think it inescapably enters into my thoughts about punishment and the emotional reactions I have to instances of punishment.
Of course this sort of Old Testament mentality is irreconcilable with other beliefs and feelings of mine, such as that revenge is wrong, that one should show mercy and practice forgiveness, etc., etc., etc. And I do mean irreconcilable, at least logically speaking; one might in practice have to strike a compromise between the desire to deal out retribution and the desire to show mercy, but the conflict seems insoluble.
In passing: If someone I love were murdered, I would find it impossible to forgive the murderer, and I would want to see him dead. I would want the state to take that desire into account when it punished the murderer, and would not consider its doing so unjust. But I would all the same regard mercy as supererogatory and feel that I would be a better person if I could accept a lesser punishment than death. And I would think that I would be a better person still if I could forgive.
Also in passing: I think that this sort of conflict is closely related to the difficulty of simultaneous belief in Hell and the Christian God. (I do not say that the notion of Hell poses an insurmountable problem for the Christian who believes in its existence, any more than I would say that the problem of evil poses an insurmountable problem for the theologian who articulates a theodicy.)