A SET OF SPECIFIC BEHAVIORAL IMPLICATIONS WERE DERIVED FROM A SIMPLE ECONOMIC MODEL OF MURDER AND DEFENSE AGAINST MURDER AND TESTED AGAINST AVAILABLE DATA. THE THEORETICAL ANALYSIS PROVIDED SHARP PREDICTIONS CONCERNING THE SIGNS AND THE RELATIVE MAGNITUDES OF THE ELASTICITIES OF THE MURDER RATE WITH RESPECT TO THE PROBABILITY OF APPREHENSION AND THE CONDITIONAL PROBABILITIES OF CONVICTION AND EXECUTION FOR MURDER. IT SUGGESTED ALSO THE EXISTENCE OF A SYSTEMATIC RELATION BETWEEN EMPLOYMENT AND EARNING OPPORTUNITIES AND THE FREQUENCY OF MURDER AND OTHER RELATED CRIMES. ALTHOUGH IN PRINCIPLE THE NEGATIVE EFFECT OF CAPITAL PUNISHMENT ON THE INCENTIVE TO COMMIT MURDER MAY BE PARTLY OFFSET BY THE INCENTIVE TO ELIMINATE WITNESSES, THE RESULTS ARE NOT INCONSISTENT WITH THE HYPOTHESIS THAT CAPITAL PUNISHMENT REDUCES THE MURDER RATE. (AUTHOR ABSTRACT MODIFIED)