Objective: The expansion of technology enables closer examination of human biological functioning which has exponentially increased knowledge about how the human organism interacts with surrounding environs to produce certain behaviors. The contemporary biosocial model pushes crime theorists and researchers alike to consider the many biological factors that may be implicated in violent behavior and how those factors are ameliorated or exacerbated by environmental influences (and vice versa). This paper describes the human microbiome and discusses why and how the human microbiome should be incorporated into biosocial investigations of violent behavior.

Method: To date, a fairly significant knowledge-base has accumulated regarding the evolutionary, genetic, and sociological bases of violent behavior but has not yet carefully considered other factors related to biochemistry: namely, the microbiome. We review the emerging literature on the role of the microbiome on phenotypes––particularly antisocial behavior––and synthesize the contribution of this literature to the study of antisocial behavior.

Results: The microbiome is likely an important contributor to animal and human behavior. Recent studies show that the microbiome holds promise in explaining antisocial behavior among a wide range of species including humans.

Conclusion: Criminological theory and public policy can incorporate knowledge about the microbiome in the explanation of violent behavior, and prevention and intervention efforts.