The Night of the Long Knives by Fritz Leiber

_We are always, thanks to our human nature, potential criminals. None of us stands outside humanity's black collective shadow._ -- The Undiscovered Self, _by Carl Jung_

Ordinarily scroungers who hide around on the outskirts until the killing's done and then come in to share the loot get what they deserve -- wordless orders, well backed up, to be on their way at once. Sometimes they even catch an after-clap of the murder urge, if it hasn't all been expended on the first victim or victims. Yet they _will_ do it, trusting I suppose to the irresistible glamor of their personalities. There were several reasons why we didn't at once give Pop this treatment.