I disagree SY. While I don't believe a single act that is the murder of one or more people warrants the death penalty, I do believe that, in protecting itself, society has every right to put to death someone who has shown a complete disregard by leaving a trail of bodies in their wake is a clear and present danger even if locked up.
If we lock them up for life, society has to pay a price for these animals (and make no mistake, a person who wantonly takes life wherever he finds it is not actually a person, but an animal) and paying for their every need in prison is an undo burden on society for someone who has proven to not belong in society.
So we put them down like rabid animals because, let's face it, they are animals. If they get paroled they will kill again, and if they escape they will kill again. So putting them down like one would a rabid dog, is more efficient. The needs of the many out weigh the supposed right (I would argue they renounced that right when they started their killing spree) of the mass murderer.
Now, I do *not* agree with killing a person who committed one act, even premeditated, as it is a single incident.
In short, Ray Jasper should *not* be executed, but executing Jeffrey Dahmer was for the good of society and not murder. Ray Jasper would most likely not kill again if he ever did get paroled. If Dahmer had gotten paroled or escaped, he would resume his murderous acts and there was no reason to pay for him to continue living. So either we put him down, or we throw him in a cell with no food or water and he dies of starvation/dehydration as he had not earned his place in a civilized society.