Exam and Evidence Collection Procedures (continued page 4)

Wet-mount evaluation.1 Some jurisdictions require examiners to conduct wet-mount examinations of vaginal/cervical secretions for motile and nonmotile sperm in cases in which a male suspect may have ejaculated in a patient’s vagina.2 Because sperm motility decreases quickly with time and removal from the vagina/cervix,3 wet-mount evaluation during the exam can provide the only opportunity to see sperm motility.4 The presence of motile sperm may help narrow the timeframe that the crime could have occurred.

In most jurisdictions, however, the crime lab is responsible for all analysis of evidence5 and examiners do not do the wet-mount evaluation for sperm.5 Follow jurisdictional policy on whether wet-mount evaluation for sperm is needed and methods of evaluation. If it is required, examiners must be educated on use of the microscope, identification of sperm, and reporting their findings and have quality assurance mechanisms in place to assure the accuracy of their findings.

  • If necessary, prepare a wet-mount slide according to jurisdictional policy. Dab one swab collected from the vaginal pool on a slide.6 Typically, the slide is prepared by placing one drop of normal saline onto the “dab” of vaginal material just placed on the slide. Place a cover slip on the slide.

  • View for presence of sperm under a microscope at 400x or by using a phase contrast or other optically staining microscope (within 10 minutes of preparing slide).7

  • Air-dry this swab and slide (not removing the cover slip).

  • Package swab and slide, place in envelope, label as “wet mount” (specifically indicating sampling site), seal, and initial the seal.


While the speculum is still in place and after all swabs and evidence have been collected, any necessary medical cultures may be taken, if medically indicated.

Penile sample

  • Slightly moisten swabs with distilled water and thoroughly swab the external surface of the penile shaft and glans. Swab all outer areas of the penis and scrotum where contact is suspected. Avoid swabbing the urethral meatus.

  • Gently roll the swabs over one of the microscope slides, according to jurisdictional policy.

  • Air-dry swabs and slides.

  • Package slides and swabs, place in envelope, label, seal, and initial the seals.

Perineal area sample8

  • If there was vaginal/anal contact, there may be leakage of semen in the perineal area. Use an alternate light source on the anal area and flake off or swab areas of dried secretions using a moist swab followed by a dry swab.

  • Optional—smear swabs on microscopic slides, according to jurisdictional policy.

  • Flaked dried secretions should be placed into the provided container. Air-dry swabs and slides and package them separately. Place in envelope, label, seal, and initial the seal.

  • Avoid contaminating anal/rectal samples by cleansing the perianal area after external secretions and foreign materials have been collected.

Anal/rectal sample9

  • Collect swabs from the anal cavity.10 Avoid contact with external skin surfaces.

  • Optional—smear swabs on microscopic slides, according to jurisdictional policy.

  • Air-dry swabs and slides.

  • Package swabs and slides, place in envelope, label, seal, and initial the seal

At this time, any additional examinations or tests involving the anus should be conducted.

Known blood or saliva sample or buccal (inner cheek) swab for DNA analysis and comparison. Many samples collected during the exam contain a mixture of secretions. To interpret DNA profile results obtained from these swabs, it is essential to know the DNA profile of patients. Patients’ DNA reference samples are used for this purpose. Follow jurisdictional policy regarding the type of samples accepted by the crime lab. Collection of a buccal swab or saliva sample is encouraged unless it is medically or forensically necessary to take blood. If a blood sample is collected, the most noninvasive method of collection should be used.

Buccal swabs: Decide on a case-by-case basis whether it is appropriate to collect a buccal swab reference sample for DNA typing rather than a blood sample. For example, a blood sample may not be needed or patients might not allow blood to be drawn. (Note that buccal swabs and saliva samples are not suitable for blood typing and serology.) If oral copulation is asserted or suspected, a buccal swab or saliva sample for patients’ DNA reference may be contaminated. In those cases, blood is usually the better reference sample. However, examiners should consult local crime labs to ensure their collection methods reflect the lab’s preferred method.

  • Buccal swab: Have patients rinse their mouths with tap water and then expose the inner cheek area. Swab this area with gentle pressure. Air-dry the swab, package, place in envelope, label, seal, and initial the seal.

Dry Blood

  • If drawn blood is not being collected for medical or toxicological purposes, consider dry blood collection because it is a less invasive method of blood collection and is easier to store.11

  • Using a betadine swab, wipe the tip of the left or right ring finger.

  • Using a sterile lancet, prick the finger.

  • While holding the finger over the circles on the blood collection card, milk the finger, allowing two drops of blood to fall in a circle. Repeat procedure for any remaining circles as required by jurisdictional policy (it may not be necessary to fill all circles).

  • Allow blood to air-dry according to jurisdictional policy. Fill out the patient’s name on the first line. Package according to jurisdictional policy, then place in envelope, label, seal, and initial the seal.

Drawn Blood

  • In order to minimize patients’ discomfort, collect drawn blood needed for the reference sample at the same time blood is collected for medical or toxicological purposes.

  • Blood for the reference sample may be collected in lavender-top and/or yellow-top blood drawing tubes. These colored tubes contain preservatives suitable for forensic blood typing. The color to use is typically specified by the designated crime lab.12 If tubes are included in the evidence collection kit, check expiration dates and replace if expired.13 Mix according to jurisdictional policy.

  • Write the patient’s name, date and time of collection, and the collector’s initials on the tube. Package according to jurisdictional policy, then place in envelope, label, seal, and initial the seal.

Collect other evidence.

Other evidence may be collected beyond what is needed for the sexual assault evidence collection kit. This could include toxicology samples or other evidence based on the unique facts and circumstances of the case.

Miscellaneous swabs may be collected, depending upon the area of contact noted in the medical forensic history. Some jurisdictions are collecting wet to dry swabs from the surfaces surrounding orifices that were penetrated or that had touch contact during an assault (e.g. area surrounding the mouth in the case of an oral assault, or the inner thighs in a vaginal penetration).

Toxicology samples. Make the decision about whether to collect toxicology samples for forensic purposes, what to collect, and collection methods according to jurisdictional policy. Do not put toxicology samples in the sexual assault evidence collection kit, unless otherwise indicated. Identify which forensic labs the jurisdiction has selected to analyze these samples, choose a lab, and follow transfer policies. (See C.7. Alcohol- and Drug-Facilitated Sexual Assault for more information on collecting toxicology samples.)

Dental floss. Use of dental floss is not recommended for additional evidence collection in cases with oral penetration. Flossing can create increased opportunity for infection through microtrauma to the gums.

Keep medical specimens separate from evidentiary specimens collected during the exam.

Specimens collected for medical purposes should be kept and processed at the medical facility, and specimens collected for forensic analysis should be transferred to the crime laboratory or other specified laboratories for analysis (with patients’ consent). It is not necessary to maintain the chain of custody on medical specimens—instead, follow exam facility policy for documenting medical care and storing medical records. Exam sites that perform exams for military installations should consider Memoranda of Understanding to address such issues as storage of evidence.


 Table of Contents Alcohol and Drug Facilitated Sexual Assault

 

 

 

1 If and when wet-mount evaluation for sperm is done, examiners should exercise discretion conducting this procedure in the presence of patients and be sensitive in explaining the implications of positive and negative wet mounts to patients (if they want to know). Examiners should remind law enforcement investigators that a lack of sperm does not mean an assault did not occur and that the crime lab will later examine prepared slides using stains and other techniques not available to examiners. Thus, if sperm is present, the lab’s rate of identification will probably be higher than it was for examiners. Providing this information might help deter misinterpretation of results.

2 In most cases, sperm becomes nonmotile in the vagina within 10 to 12 hours after ejaculation. (Drawn from W. Green, M. Kaufhold, and E. Schulman, Sexual Assault Evidentiary Exam Training for Health Care Providers, Participant Manual, 2001, p. 39 of Module 7.) Both motile and nonmotile sperm may be found in the cervix for longer periods of time after the assault than in the vagina. Sperm may not be found after an assault for many reasons (see section in this chapter on the importance of semen evidence).

3 Drawn from W. Green, M. Kaufhold, and E. Schulman, Sexual Assault Evidentiary Exam Training for Health Care Providers, Participant Manual, 2001, p. 39 of Module 7.

4 A possible exception may be toxicology analysis.

5 While crime labs can reliably identify the presence of sperm on permanent stained slides, they cannot identify motile sperm due to time delays. Information about the presence or absence of sperm and motile sperm obtained at the time of the exam can impact the investigation and patients’ decision making. One concern related to examiners doing wet-mount evaluations for sperm is that their findings may be different than those of crime labs (e.g., the examiner may not detect sperm, while the crime lab does).

6 Alternate methods for obtaining materials for wet mounts: a sample may be collected from a vaginal aspirate or fluid from the lower bill of speculum after withdrawing it from vagina, or sperm are occasionally found on microscopic urinalysis. (W. Green, M. Kaufhold, and E. Schulman, Sexual Assault Evidentiary Exam Training for Health Care Providers, Participant Manual, 2001, p. 38 of Module 7.)

7 Examiners rather than hospital lab personnel should view these slides. Otherwise, delays between preparation of slides in the exam room and analysis in the hospital lab could cause a negative result (e.g., sperm present, but not motile). Also, those involved in the chain of custody of this evidence should be kept to a minimum.

8 See the next footnote for patients with spinal cord injury and/or history of autonomic dysreflexia.

9 Note that for patients with spinal cord injury and/or history of autonomic dysreflexia, collection of anal/rectal samples is performed only with the highest level of awareness of risks and with observance of precautionary steps. Possible triggers for autonomic dysreflexia are anxiety, pelvic exam (a cold speculum or the pressure of manipulating a speculum or manipulation of the cervix and pressure on the uterus), rectal exam or swabbing, impacted bowel, urinary retention, a kinked catheter, a bladder infection, and deep skin lesion. Some symptoms are highly elevated blood pressure, nasal congestion, sudden onset of headache, flushing, sweating, shortness of breath, and muscle spasm. Precautions against a possible attack requires an empty bladder or leg bag for the exam; application of lidocaine gel to perineum and/or anal area before exam; examination performed in a semi-supine position; slow insertion and minimal manipulation of a warm speculum; constant monitoring of blood pressure and “checking in” with patients; having rapid acting anti-hypertensive medication on hand; and making health care staff aware of risks and on alert. Treatment for autonomic dysreflexia includes stopping the exam, bringing patients to sitting or semi-supine position, and involving emergency medical staff immediately who can administer a fast- acting anti-hypertensive medication. (Commonwealth of Massachusetts SANE Protocol, 2002, p. 40.)

10 If needed, an anoscope can be used to identify anal injuries and obtain anal swabs after perianal cleansing. These swabs should be obtained by direct visualization from the rectal mucosa visible above the tip of the anoscope. If patients are unable to tolerate a water- moistened anoscope or anal speculum, lightly coat the instrument with lidocaine jelly or use manual traction and obtain samples from the anal canal. If a lubricant (other than water or saline) or lidocaine jelly is used, document its use and the reason for it. (The California Medical Protocol for Examination of Sexual Assault and Child Sexual Abuse Victims, 2001, p. 48.) The examiner should use discretion in determining whether a case warrants the use of the anoscope for medical and/or forensic purposes, as well as obtain patients’ informed consent for anoscopy. Particularly if a patient has been anorectally penetrated, that patient may be uncomfortable with the use of the anoscope and could possibly even feel revictimized by it. The discomfort this procedure may cause the patient should be weighed against its potential medical or forensic uses.

11 Several state protocols indicate dry blood collection is an acceptable method to obtain known DNA samples.

12 The California Medical Protocol for Examination of Sexual Assault and Child Sexual Abuse Victims, 2001, p. 52.

13 Drawn from Connecticut’s Video Training Program, Part 1, The Examination: Sexual Assault Evidence Collection, 199