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Evolution of Forensic Nursing Theory——Introduction of the Constructed Theory of Forensic Nursing Care: A Middle-Range Theory

Valentine, Julie L. PhD, RN, CNE, SANE-A1; Sekula, L. Kathleen PhD, PMHCNS, FAAN2; Lynch, Virginia RN, FAAFS, FAAN

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doi: 10.1097/JFN.0000000000000287


The theoretical basis for forensic nursing was first established through a conceptual model, the integrated practice model for forensic nursing science, developed by Virginia Lynch as her master’s thesis project (Lynch, 1990). At the time of the conceptual model development, forensic nursing was a comparatively unrecognized professional specialty. The integrated practice model for forensic nursing science was pivotal in the establishment of forensic nursing as both a nursing and forensic specialty. Indeed, forensic nursing was acknowledged as a forensic specialty by the American Academy of Forensic Sciences in 1991, following Lynch’s presentation on forensic nursing based on the conceptual model. In 1992, forensic nursing pioneers established the International Association of Forensic Nurses (IAFN). Three years later, the American Nurses Association granted specialty status to forensic nursing. The integrated practice model for forensic nursing science was further described and refined in publications of Forensic Nursing, which featured the conceptual model as the theoretical background for the profession (Lynch & Duval, 2006, 2011).

Forensic nursing has advanced significantly over the past 30 years since the introduction of the integrated practice model for forensic nursing science with improved understanding of the scope of practice, roles and responsibilities, educational guidelines, and professional priorities (American Nurses Association & IAFN, 2017; IAFN, n.d.; Price & Maguire, 2015). In addition, research studies have clarified the role of forensic nurses and their impact within an interdisciplinary, global sphere (Campbell et al., 2011, 2012, 2005; Corum & Carroll, 2014; Drake et al., 2018; Schmitt et al., 2017; Valentine et al., 2016). To match the growth of the practice and science of forensic nursing, the theoretical basis for the profession should progress beyond a conceptual model. In 2014, a critique of the integrated practice model for forensic nursing science was published with a response from Virginia Lynch supporting the premise that it was time for the conceptual model to advance to a more defined theory, specifically a middle-range theory, to support the growth of forensic nursing science (Lynch, 2014; Valentine, 2014). Theory evolution from a conceptual framework to a middle-range nursing theory will strengthen the scientific base of forensic nursing by supporting interdisciplinary research to further define and improve forensic nursing practice, education, and research. The purpose of this article is to introduce and describe the constructed theory of forensic nursing care: a middle-range theory developed from the conceptual model, the integrated practice model for forensic nursing science.


Theory provides a creative and rigorous structuring of ideas that project a tentative, purposeful, and systematic view of phenomena (Chinn & Kramer, 2015). Although theory frames our thoughts, beliefs, and actions, nurses often ask what the value of theory is in their daily practice. In attempting to answer that question, Glanz et al. (2018) proposed that theories are important in a discipline as they shape the field, define the scope of practice, and determine future nursing practice by influencing education and socialization. Quite simply, theory helps make sense out of why nurses do what they do.

Theories provide us with two types of understanding: explanatory, which describes concepts and interactions among concepts, and predictive, which anticipates outcomes. As a practice profession, nursing requires both explanatory and predictive understanding to move theory into practice through application of the nursing process. Explanatory understanding primarily guides the nursing process steps of assessment, diagnosis, and planning, whereas predictive understanding influences the nursing process steps of planning, interventions, and evaluation. Yet, explanatory and predictive understanding are interactive building blocks of knowledge guiding each step of the nursing process.

Nursing Theory and Middle-Range Theory Development

Nursing theory has progressed substantially over the past 50 plus years. Dickoff and James (1968), not nurses themselves, were the first to challenge nurses to think about theory development and application to substantiate the practice of nursing. Following publications by Dickoff and James (1968), nurses began to study philosophy and explore the application of theory to support and direct research and practice to advance nursing science. Nursing history from the 1960s and 1970s involved the debate among nurse academicians on the proper approach of applying philosophy to develop theory and expand nursing science to guide practice. Kikuchi (1992) accurately summarized that, without an understanding of philosophy in nursing, there can be no science of nursing. Guyer and Wood (1992) emphasized the need for theory to guide practice in their well-known statement, “Theory without practice is empty; practice without theory is blind” (p. 109). Through the years, nursing theory became defined as “a set of interrelated concepts, definitions, and propositions that present a systematic view of events or situations by specifying relations among variables, in order to explain and predict events or situations” (Glanz et al., 2008, p. 26).

Early in the development of nursing theories, nurses focused on abstract theories such as conceptual models and grand theories while debating the structure and methods for developing focused, practice-oriented theories such as middle-range theories (Higgins & Moore, 2000). Chinn and Kramer (2011) elucidated the importance of middle-range theories in nursing, “Substantive middle-range theory can inform practice and lead to new practice approaches as well as investigate factors that influence the outcomes that are desired in nursing practice” (p. 48). Middle-range theories are viewed as essential to building nursing knowledge as they contain both explanatory and predictive understanding allowing for empirical testing and clear application to practice, education, and research (Lenz, 1998a, 1998b; Liehr & Smith, 1999, 2017; Peterson & Bredow, 2009; Smith & Liehr, 2014). Recently, with the emergence and proliferation of the doctor of nursing practice degrees, the need for middle-range theories as frameworks for evidence-based practice projects has grown (Liehr & Smith, 2017). Middle-range theories not only serve to structure evidence-based projects and research studies by providing testable propositions but guide the interpretation and application of the findings. In essence, middle-range theories provide a theoretical lens to illuminate practice, education, and research, thereby stimulating research and structuring knowledge to guide nursing practice and build nursing science.

Methodology of Theory Evolution to a Middle-Range Forensic Nursing Theory

The integrated practice model for forensic nursing science (see Figure 1) introduced in 1990 defined the role of forensic nursing as both a nursing and forensic specialty and established the collaborative nature of forensic nursing with criminal justice and forensic science partners (Lynch, 1990). As a conceptual model, the integrated practice model was based on relevant sociological, philosophical, and nursing theories and sought to link nursing theories with other disciplines to provide direction in caring for patients affected by violence (Valentine, 2014; Waldman & Neill, 2016). The conceptual model presented abstract concepts and assumptions gleaned from other theories to define forensic nursing as a unique, interdisciplinary profession.

Pictorial model of the integrated practice model for forensic nursing science.

The first step in nursing theory evolution from a conceptual model to a middle-range theory involved a critique of the existing conceptual model. A critique published in 2014 of the integrated practice model for forensic nursing science indicated that, although the conceptual model defined the role of forensic nursing within an interdisciplinary context, the core components of the theory (assumptions, concepts, and propositions) needed clarification and consistency (Valentine, 2014). Specifically, the critique addressed the need for the theory propositions to evolve into relational statements to clearly support practice, education, and research. The theoretical components of the underlying philosophical theories, assumptions, concepts, and propositions ought to build upon one another to clarify and strengthen the theory. When the theoretical components are clearly linked and support the propositional statements, then growth in nursing science occurs through theory-driven research (see Figure 2).

Theoretical components leading to growth in science base.

The evolution from a conceptual framework, the integrated practice model, to a middle-range nursing theory required inductive and deductive reasoning as middle-range theories are developed from both processes (Chinn & Kramer, 2011; Liehr & Smith, 1999, 2017; Peterson & Bredow, 2009; Smith & Liehr, 2014). Inductive reasoning occurs from practice and research leading to observations and conclusions, whereas deductive reasoning indicates application of existing theories and abstract concepts to emerging ideas or theories. Inductive reasoning for the middle-range theory development required a synthesis of seminal and current literature related to forensic nursing and theory development, as well as the theorists’ experiences providing forensic nursing care and conducting forensic nursing research. Deductive reasoning for this theory development required exploring additional philosophical theories and assumptions and their application to the current state of forensic nursing.

The Constructed Theory of Forensic Nursing Care: A Middle-Range Theory

The constructed theory of forensic nursing care: a middle-range theory is not meant to replace the integrated practice model for forensic nursing science, but rather build upon the constructs within the established conceptual model. The constructed theory of forensic nursing care theory components are reviewed in the following order: name or title, underlying theoretical and philosophical foundations, assumptions, concepts, and propositions (see Table 1).

TABLE 1 - Definitions of Theory Components
Theory component Definition
Theory name or title Theory name that accurately represents the main tenets, focus, and abstraction level of the theory.
Theoretical and philosophical foundations Principles that provide foundational background and support for the assumptions, concepts and propositions in the theory.
Assumptions Statements accepted as guiding truths within a theory. Assumptions emanate from the theoretical foundations and form a basis for the resulting concepts and propositions.
Concepts Definitions of the subject matter or phenomena presented in a theory. Theories have increased clarity, applicability, and strength when concepts are clearly defined.
Propositions Statements describing the relationships between two or more concepts. Propositions stimulate research as the statements are meant to be tested.

Theory Name or Title

The name of a middle-range theory should reflect the central ideas represented in the theory and designated theory abstraction level. The title of the conceptual model, integrated practice model for forensic nursing science, contains the word “integrated,” which was the optimal adjective to describe the model that created the foundation for the profession by integrating philosophies, theories, and concepts from nursing and other disciplines to define forensic nursing as a unique profession. In many ways, this early conceptual model was similar to creating a dot-to-dot picture and connecting the dots to create a picture of forensic nursing. The new middle-range theory is represented by the word “constructed,” as this implies building upon, establishing, and bringing together various elements into a cohesive whole. “Constructed” also connects the theory to constructionism, which suggests that scientific growth is influenced by historical and cultural influences (Reed & Shearer, 2011). As expected, the global culture surrounding and influencing forensic nursing in 1990 has changed over the past 30 years. The conceptual model outlined the picture of forensic nursing, whereas the middle-range theory is poised to augment the growth and construction of forensic nursing into the future.

The remaining middle-range theory title provides clarification on the theory focus and level of abstraction. The phrase in the title, “forensic nursing care,” is essential as it represents the core disciplinary perspective of nursing—nursing care. Nurses provide care to patients, whether the patient is an individual, family, group, community, or population. The primary focus of the middle-range theory is to improve outcomes of patients impacted by violence and trauma, from individuals to populations, through forensic nursing care. The final portion of the theory title clearly states the abstraction level as a middle-range theory.

Theoretical and Philosophical Foundations

The integrated practice model for forensic nursing science referenced six nursing theories, three sociological theories, and one ancient philosopher, Plato. The constructed theory middle-range theory remains grounded in the philosophical foundations of the integrated practice model but reinforces the theoretical base with the addition of three nursing theories, a social theory and two healthcare models (see Table 2).

TABLE 2 - Underlying Nursing, Philosophical, and Social Theories and Models
Nursing theories Philosophical and social theories
Theories and models from the integrated practice model for forensic nursing science
 Patterns of knowing theory (Carper, 1978) Plato on truth (Plato, 427–347 B.C.)
 Novice to expert theory (Benner, 1984) Social interaction theory (Mead, 1934)
 Theory of culture care diversity (Giger & Davidhizer, 1991) Deviant behavior (Farrell & Swigert, 1982)
 Fundamental patterns of knowing (Chinn & Kramer, 1995) Role theory (Conway & Hardy, 1988)
 Transcultural nursing theory (Leininger, 1995)
 Humanistic nursing theory (Paterson & Zderad, 1998)
Additional theories and models for the constructed theory of forensic nursing care: a middle-range theory
 Caring science (Watson, 1979, 1985, 2008) Social justice theory (Rawls, 1971, 1999)
 The quality-caring model (Duffy, 2009, 2018) Biopsychosocial model of health (Engel, 1977)
 Emancipatory nursing praxis: a theory of social justice in nursing (Walter, 2017) Trauma-informed care model (SAMHSA, 2014)

Lynch (1990, 2006, 2011) delineated the foundational support of the referenced nursing theories to frame the role development of forensic nursing. Detailed background information on the theoretical basis of the integrated practice model is not the focus of this article but is available in other documents (Lynch, 1990, 2006, 2011; Valentine, 2014) The additional theories supporting the constructed theory of forensic nursing care build upon Lynch’s approach to integrate nursing theories with theories from other disciplines to support forensic nursing care. Furthermore, the additional theories incorporate the growth that has occurred in forensic nursing and provide a platform for future growth.

Nursing Theories

Two nursing theories incorporated within the middle-range theory, caring science (Watson, 1979, 1985, 2008) and the quality-caring model (Duffy, 2009, 2018), are focused on the aspect of caring as this is the defining aspect of any nursing discipline, yet not clearly featured in the integrated practice model. When Lynch developed her conceptual model, the goal was to establish a new nursing profession linking nursing science with forensic science and criminal justice. The integrated practice model met this goal through forensic nursing role conceptualization and interdisciplinary acceptance. At this time, the theory focus needs to adapt to emphasize the importance of patient care while also defining what “caring” means within forensic nursing. The IAFN website clearly states, “forensic nurses are nurses first” (IAFN, n.d.), implying that the focus of forensic nursing care is on patient care.

The third additional nursing theory, emancipatory nursing praxis (Walter, 2017), highlights the significance of social justice in forensic nursing. Indeed, the first pillar of the IAFN Strategic Plan for 2018–2022 is the social justice pillar confirming social justice as a core value within the profession (IAFN, 2018b). In 2018, the Journal of Forensic Nursing published a special issue on social justice. Guest editors Colbert and Donley (2018) asserted, “The very nature of the work of forensic nurses is grounded in social justice” (p. 51). A newly created IAFN Social Justice Committee established a definition of social justice within forensic nursing: “Social justice is the concept of ensuring that the inherent rights of all people are respected, regardless of characteristics or vulnerabilities” (IAFN, 2019).

Caring science

Watson (1979) largely began the shift within nursing theory to define the essence and science of caring. Over the past 40 years, Watson has refined caring in nursing to illuminate the concept of caring as both a unique nurse–patient connection and a way of being.

Watson notes the importance of defining caring science, caring responses, caring relationships, and carative factors within the language of nursing. In Watson’s theory, caring science is viewed as the essence of nursing and established through human-to-human connections. Caring responses are interactions that honor the patient in their current state while acknowledging their becoming or future state. Caring relationships are founded on authenticity, love, kindness, and respect. The original 10 carative factors have evolved to caritas processes to clearly connect caring with healing through human connectedness (Watson, 2008).

Watson notes the significance of the caring moment as a transpersonal experience when “two persons (nurse and other) together with their unique life histories and phenomenal field (of perception) become a focal point in space and time, from which the moment has a field of its own that is greater than the occasion itself” (Watson, 1985, p. 59). The concept of the caring moment is highly applicable to many interactions between forensic nurses and others (patients). Forensic nurses often connect with patients in moments of trauma and distress necessitating the need for nurses to create caring moments to facilitate healing.

Quality-caring model

The quality-caring model acknowledges Watson’s theoretical caring concepts and builds upon the importance of establishing distinct caring relationships: caring for the patient and family, others, self, and community. Caring relationships are defined as “human interactions grounded in clinical caring processes” (Duffy & Hoskins, 2003, p. 82). Duffy (2009, 2018) identifies eight caring behaviors to maximize the identified relationships: mutual problem-solving, attentive reassurance, human respect, encouraging manner, appreciation of unique meaning, healing environments, basic human needs, and affiliation needs.

Although the first identified relationship in the quality-caring model is caring for the patient and family, the theory also encompasses the importance of caring relationships between nurses and “others.” As forensic nurses function within an interdisciplinary sphere, “others” relates to interdisciplinary colleagues with whom nurses develop caring, supportive relationships to enhance patient care and benefit communities. In addition, Duffy’s broad view of caring relationships not only involves nurse–patient relationships but acknowledges the importance of self-care for nurses. As forensic nurses care for patients in traumatic situations and environments, nurses may suffer from vicarious trauma and compassion fatigue requiring attention to self-care.

The quality-caring model links the development of caring relationships to improved patient health outcomes (Duffy & Hoskins, 2003). As the scientific knowledge base of nursing has grown, exploration of the positive health impacts of nurse–patient caring relationships has escalated. The quality-caring model has been cited as a theoretical framework applicable to forensic nursing (Meunier-Sham et al., 2019; Office of Justice Programs, Office for Victims of Crime, 2016). Incorporation of nursing theories focused on caring within the theoretical foundations of the constructed theory of forensic nursing care confirms that the essence of nursing—all nursing—is caring.

Emancipatory nursing praxis: A theory of social justice in nursing

Walter (2017) developed a middle-range theory on social justice in nursing through an international, constructivist grounded theory study. Her goal in theory development was to improve the conceptual clarity of social justice in nursing to guide practice, education, and research. Four dynamic concepts were constructed from the data: becoming, awakening, engaging, and transforming. Movement between the concepts was found to be influenced by relational context (individual, group, organizational, community, national, and international) and reflexivity context (descriptive, self-aware, critical, and emancipatory).

The process outlined in Walter’s theory is suggestive of patterns of knowing theory, referenced in the integrated practice model, in which emancipatory knowing is defined as “the ability to recognize social and political problems of injustice or inequity…to identify or participate in social and political change to improve people’s lives” (Chinn & Kramer, 2011, p. 64). The addition of emancipatory nursing praxis theory expands forensic nurses’ understanding of social justice while connecting constructs to prior theoretical underpinnings.

Philosophical and Social Theories and Models

Three additional philosophical and social theories and/or models complete the underlying theoretical framework of the constructed theory of forensic nursing: social justice theory (Rawls, 1971), biopyschosocial model of health (Engel, 1977), and trauma-informed care model. Collectively, these theories/models substantiate the connection between forensic nursing and interdisciplinary partners while emphasizing health as a primary forensic nursing principle. The philosophical and social theories referenced in the integrated practice model focused on role development and deviant behavior. In addition, truth was listed as theoretical foundation, assumption, and concept (see Supplemental Digital Content 1: An Examination of Truth,

Social justice theory

Rawls (1971, 1999) prepared the groundwork for the concept of social justice within multiple disciplines and societies. Rawls declared that all people have basic human rights, liberties, and opportunities regardless of gender, age, race, social class, or other potentially discriminatory categories. When these concepts are applied to health care, they imply that all people in similar situations should have equity in health care and resources. In turn, when these concepts are applied to criminal justice proceedings, they imply that all people in similar situations should receive fair and equitable treatment and outcomes. Incorporation of this theory within the constructed theory of forensic nursing care’s foundational principles expands our understanding of social justice within forensic nursing and with our interdisciplinary partners.

Biopsychosocial model of health

The biopsychosocial model of health acknowledges that the state of one’s health reflects biological, psychological, and social influences. Engel (1977) introduced this model to expand the understanding of health and illness as a dynamic, complex interaction between multiple factors specific to each unique individual. The term “patient-centered” developed from the principles within the biopsychosocial model (Biderman et al., 2005; Smith et al., 2013). The biospsychosocial model has been adopted internationally to evaluate health status and guide practice, education, and research (World Health Organization, 2002).

The IAFN core value statement strongly references a patient-centered approach: “Our work will be guided and informed by our commitment to ensuring access to evidence-based, trauma-informed, patient-centered forensic nursing services” (IAFN, 2018a). Clearly, an adoption of the principles within the biopsychosocial model frames the current state of forensic nursing. In addition, as forensic nursing is an international profession, the incorporation of the globally accepted biopsychosocial model connects forensic nursing practice throughout the world. Inclusion of the biopsychosocial model also reaffirms that the grounding of forensic nursing is in health care and improved patient care outcomes.

Trauma-informed care model

Recognition of the impact of trauma on mental and physical health has grown dramatically over the past 40–50 years. The emergence of trauma-informed care principles in the 1970s was influenced by social movements connected to the Vietnam War and the expanding feminist movement. Burgess and Holmstrom (1974) identified rape trauma syndrome, bringing attention to trauma from interpersonal violence. Felitti et al. (1998) connected traumatic childhood experiences with poor adult health outcomes in the Adverse Childhood Experiences Study. In the United States, the Substance Abuse and Mental Health Services Administration (SAMHSA) has been at the forefront of creating trauma-informed approaches for healthcare delivery and services (SAMHSA, 2014).

To unify interdisciplinary approaches to trauma services, leading experts developed the following definition of trauma: “Individual trauma results from an event, series of events, or set of circumstances that is experienced by an individual as physically or emotionally harmful or life threatening and that has lasting effects on the individual’s functioning and mental, physical, social, emotional and spiritual well-being” (SAMHSA, 2014). This definition led to the identification of the three “Es” inherent in trauma: event, experience, and effects. Following a unified definition of trauma, development of a trauma-informed approach focused on the four “Rs”: realization of the effects of trauma, recognize signs of trauma, respond using trauma-informed principles, and resist retraumatization of clients and service providers. To implement a trauma-informed approach, six key principles are outlined for application across a variety of situations and settings: safety; trustworthiness and transparency; peer support; collaboration and mutuality; empowerment, voice and choice; and cultural, historical, and gender issues (SAMHSA, 2014).

As noted earlier, the IAFN Core Value Statement confirms a commitment to “ensuring access to evidence-based, trauma-informed, patient-centered forensic nursing services” (IAFN, 2018a). Caring for patients who have experienced recent and/or past trauma is inherent in the work of forensic nurses. The ability for forensic nurses to understand and apply trauma-informed care principles is essential to improve healthcare outcomes of patients and avoid secondary traumatization of forensic nurses and interdisciplinary partners. Moreover, by understanding the long-lasting effects of trauma and violence, forensic nurses work with interdisciplinary partners to prevent violence in societies.

Following the establishment of the theoretical foundations of the constructed theory of forensic nursing care, the remaining theory components are presented and defined as follows: assumptions, concepts, and propositions (see Table 3).

TABLE 3 - Theory Components of the Constructed Theory of Forensic Nursing Care
Assumptions Concepts Propositions
1. Forensic nurses provide specialized nursing care to diverse groups of individuals (victims, secondary victims, witnesses, suspects, and perpetrators of violence), families, groups and populations affected globally by trauma and violence.
2. Forensic nurses practice as part of interdisciplinary teams including other healthcare professionals, victim advocates, forensic scientists, law enforcement officers, criminal justice professionals, researchers, legislators and policy makers, and community members to care for those affected by trauma and violence and prevent violence in societies.
Forensic nurses
Forensic nursing care
Forensic evidence
Forensic science
Criminal justice system
Forensic nursing care informs, impacts, and improves:
–patient health outcomes
–forensic evidence outcomes
–criminal justice system outcomes


The assumptions within the constructed theory of forensic nursing care are derived from the theoretical foundations and led to the concepts and proposition. The first assumption broadly describes forensic nursing care as “specialized” and identifies global patient populations. The second assumption establishes forensic nursing as a collaborative profession in an interdisciplinary sphere and implies forensic nurses, as part of interdisciplinary teams, are vested in preventing violence and trauma as well as caring for those who have experienced trauma. Middle-range theories with few assumptions have higher explanatory power as only basic conditions need to be met before making a hypothesis from the propositions (Meleis, 2012).


As listed, the concepts are terms describing phenomena addressed within the constructed theory of forensic nursing care. Clear definitions of the concepts are necessary to create a unifying theoretical language.

  • Forensic nurses—Registered nurses with undergraduate or graduate degrees, licensed by a government or regulatory body to function as registered nurses with specialized education in forensic nursing care and principles (American Nurses Association & IAFN, 2017). Although forensic nurses have additional education and training related to forensic sciences and criminal justice, they “are nurses first and foremost” inferring the focus of forensic nurses remains on patients and health care (IAFN, n.d.).
  • Forensic nursing care—Forensic nursing care is founded upon theories and models referenced in this theory to provide specialized and equitable physical, mental, and emotional health care to patients impacted by violence, natural disasters, or mass destruction (American Nurses Association & IAFN, 2017). Forensic nursing care is patient-centered and trauma-informed reflecting best practices to develop evidence-based practice. Best practices are determined through employing nursing critical thinking skills and the nursing process to individualize patient care. Forensic nursing care includes the assessment, evaluation, documentation, and treatment of trauma response and injuries. Furthermore, forensic nursing care within communities also supports violence prevention through education and legislative/policy reforms.
  • Patients—Forensic nurses regard individuals, families, groups and populations affected by violence and traumatic events as their patients; from victims and witnesses of violence and disasters to perpetrators of violence. In addition, patients may be living or deceased. Often, patient populations include vulnerable and marginalized individuals and communities (American Nurses Association & IAFN, 2017).
  • Health—Forensic nurses view health as a state of wellness, as defined by patients, in a biopsychosocial perspective. As a global nursing discipline, forensic nurses support the World Health Organization’s (2015) definition of health: “Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.” Forensic nurses understand the profound effects of trauma and violence on patients’ health and well-being.
  • Forensic evidence—Forensic evidence refers to evidence collected at crime scenes or on victims, analyzed in forensic laboratories, and possibly presented in court. Types of forensic evidence include DNA, trace samples, toxicology, pathology, digital, impression and pattern, controlled substance, anthropology, and dental records (Goux, 2016). Forensic nurses generally collect, document, and package the following types of evidence: DNA, trace, and toxicology samples; although forensic nurse death investigators may interface with additional types of forensic evidence. Patient exam documentation, including photo documentation, is also evidence. Forensic nurses have expertise in determining what forensic evidence to collect and how to maintain the integrity of the evidence.
  • Forensic science—Forensic science refers to multiple branches of science in the quest to provide criminal justice information by employing the scientific method. Forensic nurses have specialized knowledge of forensic science principles to guide evidence collection, documentation, and containment.
  • Criminal justice system—The criminal justice system includes law enforcement, prosecuting attorneys, defense attorneys, judges, juries, correctional officers, and correctional facilities established by governments. Forensic nurses have specialized knowledge of criminal justice system procedures related to consulting with criminal justice professionals, testifying in court, and maintaining evidence integrity and documentation, and chain of custody. Forensic nurses strive to be objective and impartial in legal proceedings, testifying for both prosecution and defense, to help establish equitability, truth, and justice as criminal justice system outcomes.


The power of theories to advance science is in the propositions as they provide testable hypotheses. Propositions are the pinnacle of a theory. The propositions within the constructed theory for forensic nursing care are relational propositions, linking the concept of forensic nursing care to three essential outcomes:

  1. Forensic nursing care informs, impacts, and improves biopsychosocial health outcomes for patients: individuals, groups, families, communities, and populations.
  2. Forensic nursing care informs, impacts, and improves forensic evidence outcomes through thorough injury assessment, evaluation, and documentation; proficient evidence collection and documentation; and proper containment of evidence.
  3. Forensic nursing care informs, impacts, and improves criminal justice system outcomes within local, regional, state, national, and/or global communities.

Through the establishment of these relational propositions, research can be conducted to determine if in fact forensic nursing care does inform, impact, and improve health, forensic evidence, and criminal justice system outcomes. The verification of these outcomes is highly significant for the growth of the forensic nursing profession to validate the need for forensic nurses throughout society and internationally. Establishment of these relationships bolsters the social justice pillar (forensic nurses ensure inherent rights of all persons) of the IAFN Strategic Plan 2018–2022 pillars, as well as two additional pillars: access pillar (forensic nurses available in every community) and public awareness pillar (forensic nurses are valued, respected, and seen as integral to health care; IAFN, 2018a). In addition, a long-term outcome of the IAFN Research Agenda is to demonstrate that forensic nursing care improves patient healthcare outcomes (IAFN, 2018b)—the most significant proposition within the theory. The stated propositions are poised to advance the growth of forensic nursing science by inspiring and supporting nursing and interdisciplinary research.

Pictorial Model

The pictorial model of a theory should clearly represent the concepts and propositions contained in the theory (see Figure 3). The model developed for the constructed theory of forensic nursing care contains the defined concepts and visually represents the propositions. The pictorial model highlights the importance of the first propositional statement that forensic nursing care informs, impacts, and improves patient health outcomes. The emphasis on this proposition affirms that the focus of the constructed theory of forensic nursing care is on the relationships between forensic nurses and the full range of patient populations. The other two propositions are equal in importance to each other, flanking the central proposition. Although the primary direction between the concepts is forensic nursing care improving outcomes, multidirectional relationships exist between the concepts. Patient health, forensic evidence, and criminal justice outcomes should continually inform, impact, and improve forensic nursing care. In addition, the outcomes in the three categories are interrelated in a dynamic, collaborative manner.

The pictorial model of the constructed theory of forensic nursing care.


The constructed theory for forensic nursing care: a middle-range theory serves to unify the focus of forensic nursing to guide practice, structure education, and stimulate research. Although the roles and settings of forensic nurses are diverse throughout the world, the aims of forensic nursing care to provide patient-centered, trauma-informed, evidence-based, and equitable nursing care to those impacted by trauma and/or violence are universal. In addition, forensic nursing care should positively impact forensic evidence and criminal justice system outcomes due to the specialized expertise of forensic nurses. The overarching goal of the middle-range theory is to validate the critical importance of forensic nursing care to improve societies.

Theory-based practice is meant to “serve the betterment of humankind” (Cody, 1999, p. 13). Forensic nursing developed from nurses inspired to do just that—better humankind. Continued growth in forensic nursing based on theoretical principles will amplify the global impact of forensic nurses to care for humankind.


American Nurses Association & International Association of Forensic Nurses. (2017). Forensic nursing scope and standards (2nd ed.). American Nurses Association.
Benner P. (1984). From novice to expert: Excellence and power in clinical nursing practice.  Addison-Wesley.
Biderman A., Yeheskel A., Herman J. (2005). The biopsychosocial model—Have we made any progress since 1977?Families, Systems & Health, 23(4), 379–386.
Burgess A. W., Holmstrom L. L. (1974). Rape trauma syndrome. American Journal of Psychiatry, 131, 981–986.
Campbell R., Greeson M., Patterson D. (2011). Defining the boundaries: How sexual assault nurse examiners (SANEs) balance patient care and law enforcement collaboration. Journal of Forensic Nursing, 7, 17–26.
Campbell R., Patterson D., Bybee D. (2012). Prosecution of adult sexual assault cases: A longitudinal analysis of the impact of a sexual assault nurse examiner program. Violence Against Women, 18, 223–244. 10.1177/1077801212440158
Campbell R., Patterson D., Lichty L. F. (2005). The effectiveness of sexual assault nurse examiner (SANE) programs: A review of psychological, medical, legal, and community outcomes. Trauma Violence Abuse, 6(4), 313–329. 10.1177/1524838005280328
Carper B. A. (1978). Fundamental patterns of knowing in nursing. Advances in Nursing Science, 4(1), 253–259.
    Chinn P. L., Kramer M. K. (1995). Theory and nursing: A systematic approach (4th ed.). Mosby-Year Book.
      Chinn P. L., Kramer M. (2011). Integrated theory and knowledge development in nursing (8th ed.). Elsevier Mosby.
      Chinn P. L., Kramer M. K. (2015). Knowledge development in nursing: Theory and process (9th ed.). Elsevier Mosby.
      Cody W. K. (1999). Middle-range theories: Do they foster the development of nursing science?Nursing Science Quarterly, 12(1), 9–14.
      Colbert A. M., Donley S. R. (2018). Social justice and forensic nursing. Journal of Forensic Nursing, 14(2), 51–52.
      Conway D., Hardy L. (1988). The use of knowledge. Appleton & Lange.
        Corum V., Carroll J. (2014). Forensic analysts' perspectives: Sexual assault kits under the microscope. Journal of Forensic Nursing, 10(1), 50–57.
        Dickoff J., James P. (1968). Symposium on theory development in nursing. A theory of theories: A position paper. Nursing Research, 17(3), 197–203.
        Drake S. A., Koetting C., Thimsen K., Downing N., Porta C., Hardy P., Valentine J. L., Finn C., Engebretson J. (2018). Forensic nursing state of the science: Research and practice opportunities. Journal of Forensic Nursing, 14(1), 3–10.
        Duffy J. R. (2009). Quality caring in nursing: Applying theory to clinical practice, education and leadership. Springer.
        Duffy J. R. (2018). Quality caring in nursing and health systems: Implications for clinicians, educators, and leaders (3rd ed.). Springer.
        Duffy J. R., Hoskins L. M. (2003). The quality-caring model: Blending dual paradigms. ANS. Advances in Nursing Science, 26(1), 77–88.
        Engel G. L. (1977). The need for a new medical model: A challenge for biomedicine. Science, 196, 129–136.
        Farrell R., Swigert V. (1982). Deviance and social control. Random House.
          Felitti V. J., Anda R. F., Nordenberg D., Williamson D. F., Spitz A. M., Edwards V., Koss M. P., Marks J. S. (1998). Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults: The adverse childhood experiences (ACE) study. American Journal of Preventive Medicine, 14, 245–258.
          Giger J., Davidhizer R. (1991). Transcultural nursing: Assessment and intervention (2nd ed.). Mosby.
            Glanz K., Burke L. E., Rimer B. K. (2018). Health behavior theories. In Butts J. B., Rich K. A. (Eds.), Philosophies and theories for advanced nursing practice (pp. 241–265).  Jones and Bartlett.
            Glanz K., Rimer B. K., Viswanath K. (2008). Theory, research, and practice in health behavior. In Glanz K., Rimer B. K., Viswanath K. (Eds.), Health behavior: Theory, research, and practice (5th ed., pp. 23–26).  Jossey-Bass.
            Goux S. (2016). Forensic science 101. In Amar A. F., Sekula L. K. (Eds.), A practical guide to forensic nursing: Incorporating forensic principles into nursing practice.  Sigma Theta Tau International.
            Guyer P., Wood C. M. (1992). The Cambridge edition of the works of Immanual Kant. Cambridge University Press.
            Higgins P. A., Moore S. M. (2000). Levels of theoretical thinking in nursing. Nursing Outlook, 48(4), 179–183.
            International Association of Forensic Nurses, (2018a). Strategic plan 2018–2022.
            International Association of Forensic Nurses, (2018b). International Association of Forensic Nurses 2018–2020 research agenda.
            International Association of Forensic Nurses, (2019). Social justice in forensic nursing: Definition and the intersection of forensic nursing and social justice.
            International Association of Forensic Nurses, (n.d.). What is forensic nursing.
            Kikuchi J. F. (1992). Nursing questions that science cannot answer. In Kikuchi J. F., Simmons H. (Eds.), Philosophic inquiry in nursing (pp. 26–37).  Sage.
            Lenz E. R. (1998a). Role of middle range theory for nursing research and practice: Part I. Nursing research. Nursing Leadership Forum, 3(1), 24–33.
            Lenz E. R. (1998b). Role of middle range theory for nursing research and practice: Part 2. Nursing practice. Nursing Leadership Forum, 3(2), 62–66.
            Liehr P., Smith M. J. (1999). Middle range theory: Spinning research and practice to create knowledge for the new millennium. Advances in Nursing Science, 21, 81–91.
            Liehr P., Smith M. J. (2017). Middle range theory: A perspective on development and use. Advances in Nursing Science, 40(1), 51–63.
            Leininger M. (1995). Theory of culture care diversity and universality (Chap. 20). In George J. (Ed.), Nursing theories: The base of professional nursing practice.  Appleton & Lange.
              Lynch V. A. (1990). Clinical forensic nursing: A descriptive study in role development (Published master's thesis). The University of Texas at Arlington.
              Lynch V. A. (2006). Concepts and theory of forensic nursing science. In Lynch V. A., Duval J. B. (Eds.), Forensic nursing (pp. 19–29).  Elsevier Mosby.
              Lynch V. A. (2011). Concepts and theory of forensic nursing science. In Lynch V. A., Duval J. B. (Eds.), Forensic nursing science (2nd ed., pp. 10–19).  Elsevier Mosby.
                Lynch V. A., Duval J. B. (Eds.) (2006). Forensic nursing.  Elseiver Mosby.
                Lynch V. A., Duval J. B. (Eds.) (2011). Forensic nursing science (2nd ed.).  Elsevier Mosby.
                Lynch V. A. (2014). Enrichment of theory through critique, restructuring and application. Journal of Forensic Nursing, 10(3), 120–121.
                Mead G. H. (1934). Mind, self, and society. University of Chicago Press.
                  Meleis A. I. (2012). Theoretical nursing: Development & progress (5th ed.). Elsevier Mosby.
                  Meunier-Sham J., Preiss R. M., Petricone R., Re C., Gillen F. (2019). Laying the foundation for the National TeleNursing Center: Integration of the quality-caring model into teleSANE practice. Journal of Forensic Nursing, 15(3), 143–151.
                  Office of Justice Programs, Office for Victims of Crime. (2016). SANE program development and operation guide.
                  Paterson J., Zderad L. (1998). Humanistic nursing. In Patterson J. E., Zderad L. T. (Eds.), Nursing theories: The base for professional nursing practice (pp. 287–299).  National League for Nursing Press.
                    Peterson S. J., Bredow T. S. (2009). Middle range theories: Application to nursing research (2nd ed.). Lippincott Williams & Wilkins.
                    Plato (427–347 B.C.). Translated from Greek to English byJowett B. (Ed.) The Republic.  Easton Press.
                      Price B., Maguire K. (2015). Core curriculum for forensic nursing. Wolters Kluwer.
                      Rawls J. (1971). A theory of justice. Harvard University Press.
                      Rawls J. (1999). A theory of justice (Revised ed.). The Belknap Press of Harvard University Press.
                      Reed P. G., Shearer N. B. C. (2011). Perspectives on nursing theory (6th ed.). Wolters Kluwer Health.
                      Schmitt T., Cross T. P., Alderden M. (2017). Qualitative analysis of prosecutors’ perspectives on sexual assault nurse examiners and the criminal justice response to sexual assault. Journal of Forensic Nursing, 13(2), 62–68.
                      Smith M. J., Liehr P. R. (2014). Middle range theory for nursing (3rd ed.). Springer.
                      Smith R. C., Fortin A. H., Dwamena F., Frankel R. M. (2013). An evidence-based patient-centered method makes the biopsychosocial model scientific. Patient Education and Counseling, 91(3), 265–270.
                      Substance Abuse and Mental Health Services Administration. (2014). SAMHSA’s concept of trauma and guidance for a trauma-informed approach.
                      Valentine J. L. (2014). Why we do what we do: A theoretical evaluation of the integrated practice model for forensic nursing science. Journal of Forensic Nursing, 10(3), 113–119. 10.1097/JFN.0000000000000041
                      Valentine J. L., Shaw J., Lark A., Campbell R. (2016). Now we know: Assessing sexual assault criminal justice case processing in an urban community using the Sexual Assault Nurse Practitioner Evaluation Toolkit. Journal of Forensic Nursing, 12(3), 133–140.
                      Waldman J., Neill K. S. (2016). Introduction. In Price B., Maguire K. (Eds.), Core curriculum for forensic nursing (pp. 1–40).  Wolters Kluwer.
                      Walter R. R. (2017). Emancipatory nursing praxis: A theory of social justice in nursing. ANS. Advances in Nursing Science, 40(3), 225–243.
                      Watson J. (1979). Nursing: The philosophy and science of caring. Little, Brown and Company.
                      Watson J. (1985). Nursing: Human science and human care, A theory of nursing. Appleton-Century-Crofts.
                      Watson J. (2008). Nursing: The philosophy and science of caring (Revised edition). The University Press of Colorado.
                      World Health Organization. (2002). Towards a common language for functioning, disability and health. Author.
                      World Health Organization. (2015). Constitution of WHO: Principles.

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