The lesson teaches the officer to identify three basic elements of the corpus delicti of all Penal Code (PC) 261 rape crimes; to list the five alternative circumstances which may be used to establish the nonconsent of rape victims; and to define the meanings of the following six terms or phrases as they relate to sex crimes: sufficient penetration, unsound mind, sufficient mental age, unconscious of the act, the essential guilt in rape, and privity. The officer also learns to describe the nature of the one currently acceptable defense under PC 26 against a PC 261.5 charge, and to identify the essential elements of the corpus delicti of PC 261.5. The cassette instructs the officer when to use the workbook and how to check the answers. The workbook includes a posttest and instructor's answer key. For part two of this lesson, see NCJRS 75371.