The adverse effects of policing on population health: A conceptual model

While negative encounters between police and the community are not a new trend, recent high profile deaths of unarmed people of color have gained widespread national attention and ignited new movements demanding reform, accountability, and progress. Increasingly over the past few decades, researchers have examined the most extreme cases of lethal use of force, describing the context of these violent encounters, situational and personal characteristics, and underlying risk factors. More recent research has aimed to define the broader and more nuanced adverse effects that policing can have on population health. We propose a holistic and multidisciplinary model for the relationship between policing and population health in the U.S. that incorporates contextual, situational, and individual-level factors while also recognizing the direct and vicarious mechanisms by which policing exposures can negatively affect population health. The model captures the short and long term health effects of policing and the cyclic nature by which those effects at the individual, community, and systemic levels can influence each other. We consider the unique qualities of different communities that may influence these pathways, the historical trends of the criminal justice and policing systems, and recommend applications of the model in policing agencies, medicine, and research.

Biological explanations of criminal behavior

There is a growing literature on biological explanations of antisocial and criminal behavior. This paper provides a selective review of three specific biological factors - psychophysiology (with the focus on blunted heart rate and skin conductance), brain mechanisms (with a focus on structural and functional aberrations of the prefrontal cortex, amygdala, and striatum), and genetics (with an emphasis on gene-environment and gene-gene interactions). Overall, understanding the role of biology in antisocial and criminal behavior may help increase the explanatory power of current research and theories, as well as inform policy and treatment options.

The Development of Severe and Chronic Violence Among Youth: The Role of Psychopathic Traits and Reward Processing

Psychopathic traits are a manifestation of a personality pathology that comprises a core affective-interpersonal dysfunction (callous-unemotional traits) and an impulsive-antisocial behavioral component. Of particular importance, psychopathic traits are associated with the perpetration of some of the most severe acts of violence, and they appear to indicate a subset of youth at risk for earlier onset, greater frequency, and persistence of violent offending. Although these youth represent a minority of the population, they commit a significant proportion of the violence in the general community. In our review, we highlight evidence of a unique neurobiological predisposition that underlies the core affective deficits and describe contemporary accounts for the developmental processes leading to the antisocial behavior associated with psychopathy. Current evidence suggests that, for this subset of youth, the structure and function of neural circuitry supporting emotion processing, reward learning, decision making, and the development of emotion related to empathy may be crucial to understanding why they are at risk for violence. In particular, a reward dominant pattern of neurobehavioral conditioning may explain how these youth progress to some of the most severe and persistent forms of violence. However, this pattern of conditioning may also be essential to the primary prevention of such deleterious behavior. We suspect that effective strategies to prevent such violence may ultimately be informed by understanding these affective and motivational mechanisms.

'Biologizing' Psychopathy: Ethical, Legal, and Research Implications at the Interface of Epigenetics and Chronic Antisocial Conduct

Epigenetics, a field that links genetics and environmental influences on the expression of phenotypic traits, offers to increase our understanding of the development and trajectory of disease and psychological disorders beyond that thought of traditional genetic research and behavioural measures. By extension, this new perspective has implications for risk and risk management of antisocial behaviour where there is a biological component, such as psychopathy. Psychopathy is a personality disorder associated with repeat displays of antisocial behaviour, and is associated with the disproportionate imposition of harm on communities. Despite advances in our knowledge of psychopathic individuals, the construct remains complex and is hampered by a lack of integration across a range of fundamental domains. The clinical and forensic research on psychopathy is brought into conversation with the emerging field of epigenetics to highlight critical issues of (1) clinical definition and diagnosis, (2) assessment, (3) aetiology of psychopathic phenotypes, and (4) treatment and rehabilitation approaches. Broader ethical and legal questions of the role of epigenetic mechanisms in the management of psychopathy beyond the criminal justice arena are also outlined.

The Vindication of Lamarck? Epigenetics at the Intersection of Law and Mental Health

Research on epigenetic mechanisms is gaining traction, yet is poorly understood by criminologists and behavioral scientists. The current objective is to review relevant studies of interest to behavioral scientists who study crime, and to translate admittedly challenging scientific information into text that is digestible to the average criminologist. Using systematic search procedures the authors identified and reviewed 41 studies of epigenetic mechanisms in psychiatric and behavioral phenotypes among humans. Findings revealed significant epigenetic effects in an assortment of genes that are implicated in the etiology of depression, suicidality, callous-unemotional traits, and chronic and intergenerational aggressive behavior. Several polymorphisms that mediate the HPA axis, neurotransmission, immune response, brain development, serotonin synthesis, and other processes were found. Although prescriptive knowledge based on epigenetic findings to date is premature, epigenetics is a new and exciting scientific frontier not too different in spirit from Lamarck's observations centuries ago.