Study estimates that the legalization of marijuana would on average lead to increased use by 48 percent (to 19.4 percent). There would only be a modest increase of 28% among those under 30. Tax policies are effective at curbing use.

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Study estimates that the legalization of marijuana would on average lead to increased use by 48 percent (to 19.4 percent). There would only be a modest increase of 28% among those under 30. Tax policies are effective at curbing use.