The Digester

A Columbia Mailman School analysis of HIDTA seizure data from 2010 to 2023 finds states that added recreational cannabis laws to existing medical programs saw a 45 percent relative decline in cannabis seizures, suggesting legal markets may displace part of the illegal supply or change enforcement focus.

Researchers analyzed 286,844 cannabis seizures from HIDTA data across all 50 states and DC between 2010 and 2023.
States that adopted recreational cannabis laws in addition to medical laws experienced a 45 percent relative reduction in average cannabis seizure counts compared with medical-only states.
The decline was evident immediately after recreational law adoption and persisted one year later after controlling for demographics, law enforcement factors, and time trends.
Authors say the drop may reflect consumers shifting to regulated markets and some illegal suppliers exiting, or a reallocation of law enforcement resources away from cannabis.
Illegal cannabis markets did not disappear, and researchers recommend further study of dispensary density, quantities seized, and how changing policies affect enforcement priorities.

Recreational Cannabis Laws Linked to 45% Drop in Police Cannabis Seizures, Columbia Study Finds

Articles