Sexual Assault Medical Forensic Examination Research Forum: Examination Technology

During this discussion, several broad questions were explored: What is the effect of the application of specific technology and techniques to collect evidence and detect injuries on case investigation and prosecution? What is the impact on the level of discomfort and side effects that victims experience from a specific technology/technique? Michael Weaver, of St. Luke’s Hospital, and Kim Day, of the International Association of Forensic Nurses, presented on this topic, focusing on:

Specialty Techniques and Technologies

Wet Mount Evaluation for Motile Sperm

  • What are the medical and forensic reasons for doing wet mount evaluation for motile sperm?
  • Which medical professionals receive training on this technique? Several participants indicated that physicians and advanced nurse practitioners may be trained; this is not a component of basic SANE training for registered nurses. Which professionals are conducting these evaluations?
  • In what percentage of SAMFEs are these evaluations conducted?
  • Who decides whether or not this evaluation is needed (e.g., is it a directive from the crime lab via the kit versus the individual decision of the examiner)? [1]
  • If conducted for forensic reasons, what are the criminal justice outcomes of this evaluation? Are the results used in court; are they impactful? It might be helpful to query prosecutors to gain consensus on whether it is used and useful. Some questions to ask: Have you ever used motile sperm in sexual assault cases? If you do that preliminary test, how often does that go to the lab? If the evaluation is positive, then do you collect a kit? And then, how often does the kit go to the crime lab? Does the crime lab also test for sperm to move it forward? How do results of this test affect the victim? How does it affect prosecution? If you find injury or semen, what difference does it make?
  • If conducted for medical reasons, what is the impact on the victim’s emotional health? Several participants concurred that if there was a quick test for presence of seminal content, it might make a difference to victims who are uncertain of what happened to them but have concerns (e.g., pregnancy or sexually transmitted disease—STI). Would the test results help them decide whether to have the exam, seek prophylactic treatment, and/or report?

Alternative Light Source (ALS)

  • What can be identified using ALS (e.g., semen stains and early bruising)? In the case of an injury, how soon after the incident/presence of the injury can it be identified as such, and what are the health outcomes for the victim? Is there a need for multiple and matching images along the way — routinely or on a case-by-case basis?
  • More generally, how are examiners and other responders asking victims about injury? Do examiners always ask SAMFE patients about strangulation? Several participants noted that response to strangulation is evolving in medicine and hospital emergency department management as to when and what to evaluate, which patients are at greatest risk, etc. Forensic documentation on strangulation should be informed by medical advances.


  • Are examiners trained to use the anoscope? What training do they receive?
  • To what extent is the use of anoscopy necessary in a case? What is the impact of sample collection and injury identification/documentation using the anoscope on the patient and investigative/prosecutorial outcomes? What are the benefits/costs of collecting an anal sample using a swab versus gaining an anal sample via the anoscopy?
  • What are the issues around contamination of anal samples? Will the examiner be able to get a “pure” sample when using the anoscope, as opposed to when using an anal swab? Several participants noted this was a training issue.
  • Why subject patients to anoscopy for evidence collection if it is over 120 hours post-assault? Several participants noted that evidence in this area is typically not available after this time.
  • What techniques are used for injury identification in the ano-rectal area? If examiners see injury in the ano-rectal area, how should they proceed without causing further injuries? Do examiners receive training to use the anoscope when injuries are involved and not harm patients more by stretching the tissue? Several participants mentioned that if examiners were not qualified to use the anoscope, they would call in either a gastroenterologist or emergency department physician who is trained.

Toluidine Blue Dye (TB Dye)[2]

  • With which patients should examiners use TB dye? Why and where should it be applied? Why would an examiner decide not to use it? Not all examiner programs use it. Several participants noted that there is disparity in identifying injury with TB dye in lighter versus darker skin-toned patients. It may not accurately interpret injuries across skin types due to lack of contrast.
  • What techniques are employed to apply TB dye to identify ano-genital injury? Are examiners being trained to properly use TB dye? It was noted there were standards to follow, although there may be variations by program. Apply dye with a cotton tip applicator and, after drying for a few seconds, wipe gently with cotton swab moistened with lubricating jelly. Diffuse uptake would be considered negative; to be positive it had to be linear with specific margins.
  • Are there times examiners should use colposcope or digital cameras instead of, or in addition to, TB dye to identify, document, or measure various facets of images? For example, several participants noted that cameras with reverse images may help detection with darker skins.
  • Is TB dye helpful in cases where the issue is consent? Is it the consensus that the presence of micro-trauma is not helpful in determining if force was used because micro-trauma is also found after consensual intercourse? Can digital images and written documentation using TB dye help inform whether the injury is more likely associated with consent or lack of consent? How would such information be used by the prosecutor? The defense? Do images using TB dye make a difference in court? It was noted that there is some research suggesting that micro-trauma should not be discounted: Marilyn Sommers, of the University of Pennsylvania’s School of Nursing, conducted research comparing 600 women with consensual intercourse with 600 rape victims. Many had micro-trauma after intercourse, but there was a difference in the type of injury that might be associated with lack of consent.
  • Using TB dye with children and adolescents appears to improve identification and documentation of injury/trauma, but what about with adults? Are there different criteria in assessing injury with TB dye at different ages? Also, how does injury look different using TB dye at different stages of recovery, and what do examiners actually document?


Broad questions included: What equipment is being used to take photographs of injuries, what techniques are used, who is taking the photographs[3] what is their level of applicable training, and how are photographs stored and protected? How is photo-documentation of bodily and ano-genital injuries being used from the victim’s health and criminal justice standpoints? Participants cited the potential usefulness of photographs to the investigation and prosecution, medical care, and examiner quality assurance, peer review, and education. Surveying the field for basis data and doing cost-benefit analyses were suggested:

  • What are the benefits and costs of the various photo technologies used to detect bodily and ano-genital injuries in different populations (children, adolescents, and adults)? What does each piece of equipment allow examiners to do that other equipment doesn’t (does it provide better magnification, allow a more thorough exam, require less training, etc.)? Several participants noted how examiner programs that treat adults and adolescents are moving toward using digital cameras, whereas if they see a combination of children and adults/adolescents, they often use a colposcope. With examiner programs for children, the colposcope appears to be used. Also noted was the use of video capacity with the colposcope. [4] Several participants noted their concern regarding anecdotal reports of use of personal devices such as smartphones to photo-document.
  • Is the practice of photo documentation worth the technological investment? What are the initial costs of equipment, maintenance costs, impact of multiple users, and ongoing adjustments needed to customize use for each patient/user? When equipment wears out, do examiner programs repair/update it or move on to other equipment?
  • Are patients adequately informed regarding all potential uses of photo documentation and its possible impact on them?
  • How often are ano-genital images used in prosecution (as in most cases there are no injuries)? Are they only used if they show injury? Are the actual images used or are diagrams more effective? Are they shown to the jury? If there are images shown in court, are they explained by the examiner? How does displaying these images in court impact the emotional health of victims? Does use of photo documentation make a difference to criminal justice outcomes? Does the quality of the photographs make a difference?
  • Are the benefits to victims and case outcomes worth the cost of potentially retraumatizing patients when taking these photographs, if/when these photographs are displayed in court, or if/when these photographs are used for other purposes?
  • What could examiners do to make taking photographs more tolerable for the patient if it is part of the examination? What equipment, techniques, and procedures are most acceptable?
  • What is the comfort level and level of skill among examiners in using the various types of technology to photo document? What is the impact on the victim’s health and criminal justice outcomes of an experienced versus inexperienced photographer?
  • Who has custody and control of these photographs (are they in medical storage, law enforcement storage, or lab storage)? Who should control the photographs from a victim-centered perspective? What potential confidentiality breaches are associated with different photo documentation equipment? What storage and security procedures are in place for each technology to address those potential breaches? (More discussion is needed on this topic to speak to the multitude of problems associated with using personal technology.) Several participants noted anecdotal reports of exam reports and photographs not being secured. Ultimately, the field needs standardized procedures for the storage, security, and confidentiality of forensic photographs. [5]

Foley Catheter

Several participants noted that examiners sometimes use the Foley catheter to get better images of hymen margins and detect micro-trauma in adolescent girls.

  • What is the best technique for using the Foley catheter? What are the related costs and benefits?[6]
  • What is the forensic value of the details of potential micro-trauma gained through use of the Foley catheter to criminal justice outcomes? Are images and documentation gained using the Foley catheter used in prosecution? What are case outcomes? Do the findings help examiners decide what additional evidence to collect from a patient?
  • What is the medical value of the images and information gained through use of the Foley catheter? What is the impact on patients in terms of level of discomfort or retraumatization? It is not an uncomfortable procedure.


[1] There was a trial program used in Arizona that taught SANEs to do a presumptive test for sperm and fast track the most probative pieces of evidence to the crime lab to get results more quickly (initially to link serial cases right away with DNA). It would be useful to get more specifics on this study.

[2] Concerned that TB dye had a carcinogenic effect, Michael Sheppo, of NIJ, provided participants with a material safety data sheet (MSDS) on Toluidine Blue O. In review of an early draft of this report, a participant commented that the published carcinogenic effect related to the laboratory stain was based on large quantities injected intravenously into mice. The TB dye used by examiners is Toluidine Blue O — 1 percent, containing 1percent Toluidine Blue O in 99 percent aqueous solution. The reviewer could find no data sheet identifying this 1 percent solution used by health care providers as a carcinogen; in fact, this dye is used to diagnose oral and genital cancers, is washed off within a minute, and on any other MSDS and under several laws that require reporting the carcinogenic effects, there is no reported carcinogenic effect. The worst potential side effect is mild burning or irritation with vulvar use. The reviewer stated that the key is to be patient focused, tell them the risks, and let them decide on whether they will allow its use.

[3] It was noted that examiners should be doing forensic photo documentation of patients in these cases, not law enforcement officers.

[4] A question posed to examiners during the forum: When you have practice in looking through the colposcope and seeing fine injuries, does the time come when you can see these injuries without it? One participant noted that research data are suggesting no statistical differences between what examiners can see with the colposcope versus a visual exam. It was also noted that SANEs in Canada have made convincing arguments against this technology.   

[5] This conversation raised general questions related to how involved agencies within jurisdictions deal with storage, security, and confidentiality of medical and forensic records in these cases. Where are records stored, how are they protected, who has access to them, and how do they gain access (e.g., through a password available only to them)?

[6] It was noted that “fox” 8-inch swabs with glove rayon tips can be used to collect samples in adolescent girls.

Date Created: September 13, 2012