Abstract: | This paper reports the results of the application of intervention analysis, an interrupted times series methodology, to test the deterrent response of criminal offenders faced with changes in the penalty structure for the crime of robbery with a firearm. The results are consistent with the hypothesis of general deterrence as set out by Becker and extended theoretically and tested empirically by others. Offenders in Arizona metropolitan areas rapidly reduced the number of robberies with a firearm supplied as penalties for firearm use became more severe. This finding suggests legislation which punishes those who choose to use such weapons in illegal activities may be effective while leaving intact the rights of private citizens to own firearms. One disturbing finding was that a Portion of the deterrent effect of harsher mandatory sentencing for firearm use in robbery may have been offset by substitution of other types of robbery not covered by the new legislation. |