sentences:  The Drug Enforcement Administration has reported that cannabis sales and trafficking support violent criminal gangs.Proponents of fully decriminalizing cannabis to allow the regulated cultivation and sale of cannabis, including Law Enforcement Against Prohibition, argue that fully decriminalizing cannabis would largely decrease financial gains earned by gangs in black market cannabis sales and trafficking.A study in the "Journal of Policy Analysis and Management" by Mark Anderson and Daniel Reese indicated that increased marijuana use in California is a substitute for alcohol.