Is legal 'medical' marijuana linked to high youth substance abuse rates?

Let's look at Colorado's substance abuse rates in 2011- 2012 when medical marijuana was legal but recreational pot was not, Colorado youth ages 12- 17 and 18- 25 ranked in the top percentiles for most substance abuse rates: illicit drugs, marijuana, cocaine, non-medical use of painkillers and ranked the lowest for perception of great risk of smoking marijuana.

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