Recreational Cannabis Legalization and Illicit Drugs: Drug Usage, Mortality, and Darknet Transactions.

This article empirically investigates the public health impact of Recreational Cannabis Legalization (RCL) in the United States, focusing on its effects on illicit drug use, overdose mortality, and darknet drug transactions. Using a difference-in-differences approach with data from 11 states that legalized recreational cannabis between 2012 and 2018, the study finds evidence supporting the "gateway effect," whereby RCL significantly increased illicit drug initiation, use, and overdose mortality by 34.6%. This effect is further corroborated by a substantial rise in Bitcoin transactions on darknet markets—major platforms for illicit drug trade—after legalization, especially in states with higher cannabis possession limits and lower excise taxes. The findings suggest that more lenient RCL policies may exacerbate illicit drug-related harms, highlighting the need for cautious regulatory measures, enhanced law enforcement targeting darknet markets, and ongoing monitoring to mitigate public health risks associated with recreational cannabis legalization.