The study focused on trends in the number and rates of killings of police officers across types of law enforcement agencies, and provided an explanation of interagency differences. The analysis showed that the number and rate of felonious killings fell between 1972 and 1984, and have remained relatively stable over the past decade. The greatest reductions have occurred in small cities and in rural areas. Regression analysis showed that the violent crime rate was the only factor significantly and positively correlated to the felonious police homicide rate during two study periods, 1977 to 1984 and 1985 to 1992. For 40 percent of the slain officers, the attack represented their first interaction with the offender. Incident characteristics varied by assignment and agency type. 10 references