By Robert R.J. Grispino, M.A.
Special Agent Serology Unit, Laboratory Division FBI Headquarters
NOTE: The following article presents a purely scientific approach to sexual assault evidence collection. The scientific step-by-step procedures that are explained here should always be accompanied by supportive treatment of the victim. It should also be noted that the investigating officer will be responsible for both overseeing the execution of the medical procedures described and managing the collection of the physical evidence.
Police officers throughout the United States routinely handle and oversee sexual assault investigations. Yet, these officers rarely receive training on the proper methods to be used for sexual assault evidence collection and preservation. As a result, valuable physical evidence may either be overlooked or inadvertently allowed to deteriorate biologically. This article establishes proper evidence collection and preservation protocol in sexual assault matters and demonstrates how modern forensic serology can aid in the eventual successful prosecution of the assailant.
After The Assault
A sexual assault has been committed. Upon arriving at the scene, an officer usually encounters a distraught, possibly hysterical, victim in the first psychological coping stages after an intrusively brutal assault. At this time, the victim is not usually receptive to examination, even though the ideal time to collect body fluid evidence is immediately following the assault. This best evidence of the crime is present, but unfortunately, it is degrading with every elapsed minute. It is crucial that the officer be aware of the need for immediate examination in order to ensure that evidence is collected properly.
The victim should be transported expeditiously to a local hospital or rape trauma center where trained nurses or physicians can gather the appropriate physical evidence. The investigating officer is not only responsible for accompanying the victim through the phases of the examination but must also oversee the collection and preservation of medical evidence. By being fully aware of the procedures that should take place and the evidence that can be collected, the officer will be able to ensure that the case is as complete as possible.
During this examination period, health professionals should accumulate and catalog physical evidence. The completeness of the physical examination depends on the care, consideration, and thoroughness of the examining physician. As much evidence as possible should be obtained from the victim. However, if the health professional does not gather all of the available background data, the investigating officer can and should step in to make sure that it is elicited entirely from the victim.
Interviewing The Victim
The initial victim interview is notoriously the most incomplete in sexual assault matters. The excuses are numerous. The victim is hysterical and has to be sedated. The doctor or nurse is not willing to delve into any particulars of the assault for fear that it will further upset the victim. The investigating officer is embarrassed or unsure of the situation. Yet, regardless of these various problems, a full and complete description of the assault is crucial to obtain the physical evidence needed for a successful scientific analysis.
Obvious questions regarding the date, time and location of the assault, as well as the description or identity of the subject and the general circumstances of the assault, are rarely missed. However, the less obvious questions can be just as important. The interviewer should ascertain whether the victim bathed, showered, douched, urinated, defecated, vomited, brushed teeth, or gargled with mouthwash at any time after the assault and prior to the examination. If any of these activities were performed, the probability of obtaining useful serological results could be greatly diminished.
The physician should then discuss the basics of the assault. It should be determined from the interview whether penile penetration of the vagina, anus or mouth was attempted and/or successful, as well as if the perpetrator ejaculated at any time. If penetration was unsuccessful or not attempted in certain orifices, the physician may opt not to collect evidence from the unviolated areas. The physician must realize that it may be difficult or impossible for a victim to know whether the suspect ejaculated or there maybe a psychologically induced reluctance by the victim to admit during the early post-assault period that ejaculation occurred. In these instances,failure to collect samples from all body cavities may result in lost body fluid evidence.
The extent of oral/genital sexual contact, whether fellatio or cunnilingus,should be evaluated. If contact was indicated, the medical examiner should externally swab the genital area for later serological analysis. It would also be important to determine whether the assailant used a lubricant or condom during the assault or whether the victim was menstruating.
The victim should also be asked about the particulars and extent of any consensual intercourse within a 72-hour period prior to the assault. The final serological conclusions reached from the scientific analysis of the physical evidence of the assault may be greatly affected by previous consensual sexual activity and resultant body fluid mixtures. It would then be important to obtain blood and saliva samples from the previous partner(s) for comparison and elimination purposes.
The presence and extent of any injuries to the assailant inflicted by the victim is also extremely important. The suspect may have bled on the victim from a victim-inflicted injury during the struggle. A victim during menstruation could also transfer blood to the suspect during vaginal assault, which could be serologically identified in the suspect’s underwear.
After all background information is obtained from the victim, the staff nurse and attending physician should conduct a thorough pelvic examination of the victim. All signs of pelvic injury should be documented, either in drawing or photographic form. After the background information has been gathered,the next step is to collect physical evidence from the victim as carefully and thoroughly as possible.