Why I No Longer Support Decriminalizing Marijuana

"Firstly, cannabis use is associated with an increased risk of experiencing schizophrenia symptoms, even after psychotic symptoms preceding the onset of cannabis use are controlled for. … Secondly, early cannabis use (by age 15) confers greater risk for schizophrenia outcomes than later cannabis use (by age 18). The youngest cannabis users may be most at risk because their cannabis use becomes longstanding."