Crime scene analysis and the escalation of violence in serial rape.

The current study examines the crime scene behavior manifest by 108 serial rapists responsible for the perpetration of 565 rapes across various cities within the US. The goal of the current study is to identify which aspects of crime scene behavior reported to law enforcement by the victim are most useful in predicting, early in a series of offenses, which rapists are most likely to escalate into higher and, at times, life threatening levels of violence. Using 58 scales that quantify the verbal, physical, and sexual behavior manifest by a rapist in his interaction with his victim during his first reported rape and 36 modal variables that summarized approach, timing, demographics, and weapon usage across the series of rapes, the study attempts to differentiate between those rapists who escalate in their use of blunt force (Increasers) from those who do not (Non-Increasers). A logistic regression indicates that rapists who are white rather than of minority status and who, at the time of their first reported rape, rape their victims for longer periods of time and use more profanity are more likely to escalate in their level of blunt force than those rapists who do not exhibit these behaviors. The relevance of this type of predictive framework for law enforcement in its attempts to prioritize particular investigations is discussed.