RECORDS USED IN THE STUDY WERE POLICE REPORTS AND AUTOPSY PROTOCOLS OF THE DADE COUNTY MEDICAL EXAMINER'S OFFICE FOR 3,282 HOMICIDES DURING THE PERIOD FROM 1956 THROUGH 1975. THE FOLLOWING CLASSIFICATIONS WERE DEVISED: (1) ROBBERY/RAPE HOMICIDES (DEATHS WHERE CRIME SCENE INVESTIGATION DETAILS OR WITNESS TESTIMONY INDICATES HOMICIDE WAS AN INTEGRAL PART OF A ROBBERY OR RAPE); (2) CRIMINALS KILLED HOMICIDE (KILLING OF A CRIMINAL BY A POLICE OFFICER IN THE LAWFUL PERFORMANCE OF DUTY, KILLING OF A CRIMINAL BY A CITIZEN IN DEFENSE OF THE CITIZEN'S LIFE OR PROPERTY, AND GANG STYLE KILLING OF ONE CRIMINAL BY ANOTHER; (3) VICTIM-PARTICIPATED HOMICIDE (WHERE THE VICTIM IS THE FIRST TO SHOW OR USE A DEADLY WEAPON OR THE FIRST TO STRIKE A BLOW); AND (4) OTHER HOMICIDE (CHILD ABUSE, INNOCENT BYSTANDER TO ANOTHER FIGHT, AND VICTIM OF TRULY PREPLANNED MURDER). THE LARGEST INCREASE OVER THE STUDY PERIOD WAS IN THE VICTIM-PARTICIPATED CATEGORY IN THE NUMERICAL SENSE, BUT THE MOST STRIKING PERCENTAGE INCREASE WAS IN THE CATEGORIES OF CRIMINALS KILLED AND ROBBERY/RAPE. ALMOST ALL CRIMINALS KILLED CASES INVOLVED INDIVIDUALS ENGAGED IN THE IMPORT AND SALE OF NARCOTICS. IN CASES WHERE THE ASSAILANT WAS DESCRIBED, ROBBERY/RAPE MURDERS GENERALLY INVOLVED WHITE VICTIMS AND YOUNG NONWHITE PERPETRATORS. IT IS BELIEVED THAT THE DECLINE IN THE INEVITABILITY AND SEVERITY OF PUNISHMENT FOR MURDER DURING THE LATE 1960'S WAS PERCEIVED BY CRIMINALS IN THE STUDY. THE IMPACT OF FEAR OF CRIME AND THE AVAILABILITY OF FIREARMS ON THE HOMICIDE EPIDEMIC IN DADE COUNTY IS DISCUSSED. PLANNED USE OF THE CLASSIFICATION SYSTEM TO EXPLORE CAUSALITY FACTORS IN MURDER CASES IS NOTED. SUPPORTING DATA AND A LIST OF REFERENCES ARE INCLUDED. (DEP)