If this study's legitimate, people who use hard drugs are predisposed to do so. Marijuana plays no role in it.
No, not true: if you bust MJ smokers, you are going to get those who will graduate to harder drugs as well and possibly prevent that from happenning.
You are also going to bust people who would not have progressed to harder drugs. But nobody said that that is the sole reason for butsting them either.
Not true. There's no graduation here. People who use hard drugs are predisposed to do so---that's what the article suggests. The article suggests that marijuana use plays no role in the equation other than being the first illegal drug to which people---all people, hard drug users or not---are typically exposed.Policy-wise, you're advocating a Catch-22 system: keeping marijuana illegal to act as an indicator for future criminality where the only reason it's an indicator at all is because it's illegal. Perhaps there are better, more effective ways of predicting future hard drug use/future criminality of this type?
You are also going to bust people who would not have progressed to harder drugs. But nobody said that that is the sole reason for butsting them either.
Can you name another reason pot smokers should be busted?