Exploring the Link Between Marijuana Use and Violence

Herschel Baker of Drug Free Australia has compiled research references that explore the links between marijuana use and violence globally. This article reviews various studies and findings that highlight the association between marijuana consumption and violent behaviour, emphasising the need for further research in this area.

Marijuana and Violence: A Global Perspective

Case Reviews and Research Findings

General Population and Mental Illness: The review indicates a connection between marijuana use and violence, particularly in individuals with mental illnesses where psychosis is present. The findings suggest a need for more research to understand the public health implications of marijuana use.
Intimate Partner Violence: Research shows that marijuana use increases the risk of intimate partner violence. Prevention strategies should incorporate marijuana prevention efforts to reduce recidivism in domestic violence cases. Programs that address the overlap between marijuana use and intimate partner violence could offer more comprehensive treatment.
Youth and Physical Violence: A meta-analysis of 30 studies involving 296,815 individuals found a moderate association between cannabis use and physical violence. Regular cannabis users were almost three times more likely to commit violent offences compared to non-users. The study suggests that prolonged cannabis use alters brain function, reducing temper control and increasing irritability.

Mental Health and Cannabis Use

Self-Harm and Mortality Risk: Cannabis use disorder is linked to self-harm, all-cause mortality, and death by overdose and homicide among youths with mood disorders. These findings are crucial as states consider legalising marijuana.
Mood and Anxiety Disorders: Cannabis use is associated with the onset and poorer clinical course of bipolar disorder and PTSD, though the link is less clear for depression and anxiety disorders.
Adolescence and Mental Health Risks: Cannabis use in adolescence is linked to increased risks of depression, anxiety, and suicidality in young adulthood. The high prevalence of cannabis use among adolescents poses a significant public health concern.

Cannabis Use and Broader Implications

Schizophrenia and Substance Abuse: A study found robust associations between various substance abuses, including cannabis, and an increased risk of developing schizophrenia.
High-Potency Cannabis: The use of high-potency cannabis is associated with mental health and substance use issues in adolescence, highlighting the need for careful consideration of cannabis legalisation.
Violence in Psychiatric Populations: Cannabis use is a factor in violence risk among patients with severe mental illnesses, necessitating effective interventions.