Sexual offenders are a heterogeneous group, in that there is a no single profile to encompass the entire population. Sexual offenders differ in regard to personal characteristics (e.g., demographics, personality traits, attitudes and beliefs, interpersonal skills) as well as the features of their crimes (e.g., time and place, age and gender of the victim, degree of planning, amount of force used). The term rapist is used to describe one type of sex offender. This term is reserved for individuals who commit the act of rape, which the Federal Bureau of Investigation has defined as nonconsensual vaginal or anal penetration by any body part or object or oral penetration by a sex organ.

Even within the category of rapists, there are high degrees of variability between offenders. ...