According to the general deterrence hypothesis as applied to capital punishment, the abolition of capital punishment will lead to an increase in homicide rates. To test this hypothesis, this study examined different lists of abolitionist nations and dates and then adopted a modified form of the classifications made by Bowers and Joyce. The list was compared to offense rate data from the Comparative Crime Data File. This process yielded a total of 14 sets of time series data for 12 distinct cases of abolition. In two cases, Austria and Finland, separate records for Vienna and Helsinki provided the opportunity to replicate national cases with urban data. The other jurisdictions included were Canada, Denmark, England and Wales, Israel, Italy, Netherlands Antilles, New Zealand, Norway, Sweden, and Switzerland. The study also examined vicarious deterrence -- the alleged geographic spillover of deterrence from retentionist jurisdictions to abolitionist jurisdictions; residual deterrence -- the alleged temporal spillover of deterrence from retentionist years to abolitionist years; and offense deterrence -- the prediction that postabolition changes will be most conspicuous in rates of capital offenses. The findings failed to support the general and specific deterrence hypotheses regarding the impact of capital punishment. Given the extreme and irrevocable nature of capital punishment, deterrence should be accepted as a justification for the death penalty only if this effect can be shown to be reliable, consistent, and strong. Empirical support for the deterrence hypothesis cannot meet this exacting standard, as the available evidence suggests that no deterrent effect exists, or at the very least, that no deterrent effect exists that is significant enough to justify capital punishment. Tabular data and 54 footnotes are provided.