The Evidence Behind the Mask
Written by Kathy Bell & Catherine Rossi   

Editor’s Note: This article was written before the coronavirus outbreak became a pandemic — an event that has brought personal protective equipment to the forefront of any health care discussion or decision. Please remember that masks and gloves should always be prioritized to protect patients and health care providers from the spread of infectious disease.

THE SEXUAL ASSAULT Forensic Evidence Reporting Act of 2013 recommended the development of best practices and protocols for the collection and processing of DNA evidence in sexual assault cases. Over the course of two years, a multidisciplinary group of subject-matter experts met and developed the National Best Practices for Sexual Assault Kits: A Multidisciplinary Approach. The document, published by the National Institute of Justice in 2017, contained 35 recommendations designed to ensure consistency and uniformity in the multidisciplinary approach to the collection and management of evidence specific to sexual assault patients.

The focus of this article is to specifically highlight and discuss Recommendation 11 from the National Best Practices which reads, “Due to increased sensitivity in DNA technologies, masks and gloves should be used by all medical-forensic nurses and others in the collection and packaging of evidence, especially during the collection of intimate samples.” This recommendation will necessitate a practice change for many forensic nurses. It states that “all efforts” should be employed to prevent potential contamination of samples by health care professionals. To that end, while it has become standard practice for forensic nurses to wear gloves and frequently change them during examinations and evidence collection, there has been some reluctance from the forensic nursing community to incorporate the usage of masks into their practice while caring for sexual assault patients.

Figure 1. Locard’s exchange principle

Locard’s exchange principle states that “every contact leaves a trace.” Essentially, when something comes into contact with anything else, each will take something or leave something behind. Deoxyribonucleic acid (DNA) is the genetic material that makes up all living things and is frequently used in criminal investigation. DNA technologies have become increasingly sensitive in recent years (Forensic DNA Research, 2019; Butler, 2015). Technological advancements have consistently improved the ability of the scientific community to detect DNA. With improved methodologies, low-level or previously undetected contamination may now be detected and potentially cause DNA interpretational difficulties (Tupper et al., 2019). Additionally, as human DNA is “pervasive throughout the environment, contamination may not be completely avoided.” (ibid)

As the sensitivity of these tests continues to improve, so do concerns regarding the potential increasing risks for accidental cross contamination. According to Carly Balk (2015), “When DNA contamination occurs in forensic science it has the potential to change the outcome in a criminal investigation and may have significant social and financial repercussions.” Contamination is defined as the “inadvertent addition of an individual's DNA” to an evidence sample before, during, or after a sample collection (Vandewoestyne et al., 2011). Contamination can occur directly or indirectly. Direct contamination is defined by the Scientific Working Group on DNA Analysis Methods (SWGDAM) as involving the “transfer of DNA from the source of the contamination to the evidentiary item or DNA sample” (2017). SWGDAM goes on to state that direct contamination can occur accidentally without actual direct physical contact through acts such as speaking, sneezing, or coughing on an evidentiary item. Indirect contamination is then defined as the transfer of DNA through a vector such as gloves, tools, pens, packaging, and work surfaces.

With DNA analysis, major and minor contributors are evaluated from samples. When multiple contributors are present, the person with the highest amount of DNA in a profile is considered the major contributor. The minor contributor is typically substantially less of the total DNA obtained from the sample. The minor contributor may not be present at all locations evaluated. Figure 2 shows a two-person mixture with a major contributor and a minor contributor. This part of the profile is 6 out of 23 locations that are evaluated. The major contributor is the person with the higher peaks at vWA (second location). The major peak heights are 14,180 and 14,971; the minor peak height is at 3,330. The minor is about 23% of the major here.

The graph depicted here is a 4:1 ratio mixture of female to male DNA. Image courtesy of the Tulsa Police Department Forensic Laboratory.

A sexual assault evidence collection kit (SAECK) is a package containing materials used to collect samples or evidence from the patient’s body (victim or suspect) by a medical professional such as a Sexual Assault Nurse Examiner (SANE), also known as a forensic nurse (National Best Practices, 2017). Common contents of a SAECK include swabs and envelopes designed for the collection of biological material and debris from the patient’s or suspect’s body which link the patient to the suspect or crime scene, or the suspect to the crime scene or patient. SAECK contents vary by jurisdiction, but generally recommend the collection of unknown items such as swabs from the skin and body orifices, and known standard samples such as blood, hair, and buccal swabs. Items collected are typically dependent on what the patient reports occurred during the assault. Additionally, an experienced forensic nurse will have knowledge of patterns of injury that result in the transfer of biological materials from the crime scene or suspect.

Nurses traditionally are trained to establish a therapeutic relationship to facilitate effective communication. In informal discussions with experienced forensic nurses, several themes emerge regarding resistance to the practice change of wearing a mask during evidence collection. Providers most commonly cite the following concerns:

1) I have never been told that my evidence was contaminated.

2) I do not wish to place a barrier or covering over my face while communicating with a patient who has just experienced a recent sexual assault or trauma. In other words, it is important that patients feel comfortable with the examination.

3) A mask would unnecessarily upset the pediatric population.

Developing trust and rapport is an integral component of the nurse-patient relationship and is utilized by all nurses to improve the patient care experience. Evidence collection is but one part of the medical forensic encounter, and forensic nurses often spend several hours with patients establishing rapport and offering evidence collection with a SAECK for patients who have experienced sexual assault.

The key to developing that trust and rapport, particularly with patients who have been victimized, is understanding and using a trauma-informed approach to victim engagement. Trauma-informed care is the principle that care is provided with an awareness of the patient’s recent traumatic experiences and embracing the philosophy to “do no harm”. In other words, care is taken by the forensic nurse to ensure that the patient’s care plan seeks to avoid further traumatization. A similar concept used when working with patients who have been recently traumatized is the victim-centered approach. Victim-centered care is defined by the National Institute of Justice (2017) as the “systematic focus on the needs and concerns of a victim to ensure the compassionate and sensitive delivery of services in a non-judgmental manner.” Using the elements of these two concepts will minimize the possibility of re-victimization by those who are there to help them.

Research has demonstrated that a patient who feels “accepted and noticed” will be more likely to participate in developing a trusting relationship (Erickson & Nilsson, 2008). The development of a trusting relationship is critical when caring for a patient who has been victimized. Of key concern to forensic nurses is the worry that by complying with recommendations intended initially for those working in a laboratory setting, use of a barrier such as a mask might damage the establishment of a therapeutic nursing relationship. Studies show the use of forensic nurses to conduct forensic medical examinations of sexual assault victims contributes to higher prosecution and conviction rates (NIJ, 2017).

Face-to-face communication relies almost exclusively on the senses of hearing, sight, and touch. Mehrabian’s Communication Theory divides communication into three elements: nonverbal, tone, and words (Betts, 2009). Other research indicates that tone of voice is more important than posture or words that are used. Wearing a mask can potentially hinder effective communication by muffling the tone of voice and content of what is being said because it makes it harder to hear. These concerns become increasingly important when caring for children, the hard of hearing, and the elderly.

Recommendations from SWGDAM state that a face mask or face mask and shield should be worn by nurses during evidence collection from patients. They state that the mask should “completely cover the mouth and nose” and that if a shield is worn, it should “completely cover the mouth, nose and eyes.” Additionally, “if a face mask or shield is adjusted with a gloved hand, the glove should be changed before proceeding to the next procedural step.” (SWGDAM, 2017)

The initial response of some forensic nurses regarding the use of face masks, particularly around children and adolescents, is negative. Little is known about the “fear factor” of children when masks are worn in their presence (Forgie et al., 2009). The use of a trauma-informed approach places an emphasis on attending to the victims’ emotional safety, as well as their physical safety. Every precaution should be taken to avoid contamination, but it is important to maintain a patient-centered approach. (NIJ, 2017).

In an effort to determine practice and experiences toward wearing a mask during evidence collection, forensic nurses from a national nursing organization were surveyed. There was a total of 80 responses representing practices from several states. Although not a scientific study, the survey shed light on the use of masks during evidence collection. The eight survey questions are listed below.

1) Do you wear a mask during sexual assault evidence collection?

2) If Yes or Sometimes to previous question, do you wear it during the entire exam, or only during examination of intimate body parts (i.e. genitalia, breasts)?

3) If you do not wear masks, are you aware of any case contamination?

4) If there has been contamination by examiner, what was the program's response?

5) Do you examine prepubescent and post-pubescent victims?

6) What was the overall pediatric response to the mask?

7) What was overall adolescent response to the mask?

8) What was the overall adult response to the mask?

Overwhelmingly, 77% of nurses responded that they did not wear a mask during evidence collection (Figure 3). Of those that responded Yes to wearing a mask, later in the survey they commented it was mostly worn to prevent the spread of upper-respiratory infections rather than any consideration of possible contamination of evidence.

Only four respondents (5%), had ever been made aware of any type of contamination. A few commented that they have done several thousand cases and never been told there was any type of contamination (Figure 4).

The majority of respondents worked for programs that evaluated children, adolescents, and adults. Because so few respondents stated they wore masks, it would be impossible to get any useful idea of any age group’s reaction to the nurse wearing a mask. Of those that stated they wore masks during evidence collection, all stated that the adolescents responded neutrally or positively to the wearing of masks. Of those that stated they wore masks during evidence collection with children, two reported positive responses, while three reported negative responses to mask use. A wide range of variables could influence the response of patients to the wearing of masks during evidence collection, including developmental age, practitioner approach and rapport, and possibly previous experiences with masked caretakers (Forgie et al., 2009).

Clearly, it is important for forensic nurses to understand the mechanisms of DNA transfer—not just from the perspective of guiding care and evidence collection, but also in order to minimize the risks of possible accidental contamination by the health care provider during evidence collection from patients.

As DNA testing methodologies have become more sensitive and able to generate DNA profiles from increasingly smaller quantities of DNA, recommendations have begun to state that health care practitioners should utilize additional barrier methods, such as masks, when caring for patients who have been the victims of crimes, particularly sexual assault. These recommendations appear to rely on leaps of logic, that contamination is inevitable, and a mask should be utilized in addition to gloves to prevent accidental contamination.

At this time, the authors are unable to locate any published research or case studies offering examples of accidental contamination by a forensic nurse not wearing a mask and a negative impact on subsequent criminal prosecution. Existing research currently focuses on accidental contamination within the laboratory setting only. Further research is needed in order to determine if forensic nurses wearing masks is a necessary compromise between patient care and forensic laboratory standards.

One must ask, are forensic nurses really contaminating samples? If so, what is the prevalence of this issue and are there alternatives that have not been considered to ensure that victims of crime are treated in a trauma-informed manner? In order to meet the forensic standards, as well as provide a trauma informed response, alternatives should be researched. One possibility might be for forensic nurses to have their DNA profiles identified, similar to protocols used by forensic laboratories in cases of identified contamination. Another example would be the use of pediatric-friendly masks, or having the child or a teddy bear wear a mask as well. Or, the practitioner might wear a shield only, as research has indicated that children are more spooked by masks than shields because they can still see the provider’s face (Forgie et al., 2009).

Additional research specifically addressing the prevalence of accidental contamination by forensic nurses in a health care setting is recommended.

This article appeared in the March-April 2020 issue of Evidence Technology Magazine.
You can view that issue here.

About the Authors
Kathy Bell MS, RN, DF-AFN joined the Tulsa Police Department in 1994. She provides the day-to-day operations management of the forensic nurse examiner programs. Bell is a forensic nurse, performing examinations for victims of sexual assault, domestic violence, elder abuse, and drug-endangered children. She is designated Distinguished Fellow and Founding Board member of the Academy of Forensic Nursing.

Catherine Rossi FNP-BC, RN, MSN, SANE-A, SANE-P, DF-AFN is a board-certified Family Nurse Practitioner and board-certified Sexual Assault Nurse Examiner for pediatrics, adults, and adolescents. She practices with and directs the Forensic Nursing Program with Cone Health System in central North Carolina which she established and has managed since 1997. Rossi currently serves as the President of the Academy of Forensic Nursing.


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