Certainty, Severity, and Skyjacking

A central issue in the controversy surrounding the death penalty is the question of deterrence. Specifically, does the additional severity of capital punishment over life imprisonment serve to deter potential criminals? I attempt to deal with this question by separating the effects of severity of punishment from those of certainty of punishment by examining various woys in which these factors have been manipulated in the attempt to curb the incidence of skyjacking. I conclude that increasing the certainty of punishment results in a decrease in crime, whereas increasing the severity does not, in effect arguing against the necessity of the death penulty.