A new study by researchers at the University of Pittsburgh and Rutgers University comes to some troubling conclusions regarding the effects of chronic marijuana use. The findings should give further pause to the push towards legalization in various jurisdictions.

The investigation looked at the relationship between the use of marijuana during adolescence through the mid-20s and “antisocial outcomes” among male users in their mid-30s. Potential confounding factors -- such as previous anti-social lifestyles and the co-existing use of other substances -- were controlled for by the research team.

According to the peer-reviewed publication,

[Previous] longitudinal studies have found that adolescents who chronically use marijuana are more likely than nonusers to exhibit criminal behavior and antisocial personality features in adulthood ...

[The current study shows that] young men who engage in chronic marijuana use from adolescence into their 20s are at increased risk for exhibiting psychopathic features, dealing drugs, and enduring drug-related legal problems in their mid-30s relative to men who remain abstinent or use infrequently ... this relationship is similar for Black and White men.

The findings add to the substantial body of work over the past couple years showing the severe negative public health and socio-economic impacts of marijuana use.