Fact or Faction Regarding the Relationship between Cannabis Use and Violent Behavior.

The relationship between cannabis use and violence, and to what extent this association is causal in nature, remains unclear. The aim of this scoping review was to ascertain whether cannabis use increases the risk of violence and aggression in adults. Because cannabis use can result in irritability, disinhibition, and altered cognition, it is plausible that its use increases the risk of violence and aggression and that this association is exacerbated in psychiatric illness. A search of the literature using PubMed, Scopus, and PsycINFO databases was performed; all materials published in English until April 2020 were considered. Peer-reviewed publications that assessed cannabis use and perpetration of violence or aggression in adults were included in this review. Of the 327 articles that were screened for eligibility, 19 articles met inclusion criteria for this review. Results suggest that there is a link between cannabis use and violence; however, this relationship is strictly correlational, and the strength of this relationship varies depending on the population (e.g., populations with severe and persistent mental illness versus the general population). These findings have important ramifications for treatment considerations and for public health and safety approaches.