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[a Figure 3 Type of Crime Not all participating Agents were available to classify each of the 64 homicide types (sexual, nonsexual, OF unknown). In total, the 6 Agents made 285 classifications, 64 of which were made by the Agent presenting the case. Thus, there were 221 classifica- tions that could be used for compari- son with the presenter's classifica- tions. Of these, 180 classifications (81.4 percent) agreed with the pre- senter's classification. Of the 6 Agents, 1 Agent made 57 (89 percent) of the presentations. Because the percentage of his pres- entations was so large, comparing his classifications with the presenter’s would not be informative. The agree- ment rate for the other five Agents and the number of cases they classi- fied are shown in figure 3. Given the minimal amount of information sup- plied by the presenter, these agree- ment rates are high. When the classifications of each Agent were compared with those of any other Agent, the agreement rate ranged from 77 percent to 100 per- cent. Again, these are high agreement rates. Structure of Crime Scene There were 220 classifications of the structure of the crime scene (or- Agreement of Agents’ Homicide Type Classifications With presenter’s Classification Agent Cases Classified Case Agreed Aggoment 1 62 48 77.4 2 40 35 87.5 3 55 45 81.8 4 30 23 76.7 5 27 25 92.6 RESULTS ganized, disorganized, mixed, un- known) that could be used for com- parison with the presenter’s classifica- tion. Of these, 163 (74.1 percent) agreed with the presenter. (See fig. 4.) The agreement rate between any two Agents ranged from 45 percent to 89 percent. The agreement rates of Agents with the presenter and with each other varied substantially. This appears due mainly to variation in ex- perience and involvement with the process of classifying crime scenes. The agreement rates among the three Agents routinely involved with this process ranged from 62 percent to 80 percent. Given the minimal data sup- plied by the presenter, these agree- ment rates must be considered good. However, classification in any field is a skill tearned and reinforced by con- tinuous involvement. In the medical field, for example, the diagnosis of a patient’s medical condition is similarly learned and reinforced through contin- uous involvement. The interrater reliability study evaluated the agreement of Agents in classifying homicide by the type of crime and by the structure of the crime scene. in particular, the classifi- cation of crime scenes as organized has proven to be useful in profiling of- fenders in unsolved and motiveless murders. This study demonstrated that there is reliability in the classification of crime types and scenes by BSU Agents. Given only minimal informa- tion about the crime, agreements of Agents with respect to crime types was high (at least 77 percent). Agree- ment of Agents with respect to classi- fying the crime scene, while not as high as the crime-type agreement, ap- peared to be related to Agent experi- ence and involvement in the classifi- cation process. For experienced and active Agents, who were given only minimal information about the crime scene, agreement rates ranged from 62 percent to 80 percent. More infor- mation would certainly have improved e ement rates. the agreement rates FBI Footnote Robert A. Hazelwood and John Douglas. “The Lust Murderer,” FB! Law Enforcement Bulletin, April 1980, p. 6. Figure 4 Agreement of Agents’ Crime Scene Classifications with Presenter’s Classification | Agent Cases Classified Cases Agreed Agreement | 1 62 48 77.4 2 40 28 70.0 3 55 42 76.4 4 2g 15 51.7 5 27 23 85.2 113 ___ August 1985