Cannabis: how its legalization can change the illegal drug markets in the United States
Since cannabis has been illegal for decades, legalizing it causes an instant change in the prices of other illegal drugs.
A study published in the scientific journal Addiction provides the most comprehensive evidence to date of the association between recreational cannabis laws (RCLs) in U.S. states and responses in the illegal cannabis, heroin, and other drugs in these states.
In 2021, 17 US states and the District of Columbia implemented RCLs that allow people 21 years of age and older to own, use and provide limited amounts of cannabis for recreational purposes. This study found that the implementation of RCLs was associated with the following responses in the illegal drug market in these states:
- 9.2% drop in cannabis prices on the street and in the illegal market.
- 19.5% decrease in the price of poor quality or illegal cannabis on the street.
- 64% increase in heroin prices.
- 54% increase in potency of heroin.
- 7.3% increase in street and illegal oxycodone prices.
- Street and illegal hydrocodone price increase 5.1%.
- 93% decrease in seizures by law enforcement agencies of street and illegal cannabis
- About 50% decrease in seizures of heroin, oxycodone and hydrocodone by law enforcement
Lead author Dr Angélica Meinhofer (Assistant Professor of Population Health Sciences at Weill Cornell Medicine) says: “Our exploratory results suggest that illegal drug markets may not be independent of legal regulation of the cannabis market. As implementation data becomes available, we will need to do more research to determine if recreational cannabis laws are causing these changes in the illegal market and what happens in the long term.”
This study used an analysis of differences in phased implementation of RCLs in 11 states to compare changes in outcomes between RCL and non-RCL states. This study used crowdsourced data from Price of Weed and StreetRx on the price and quality of illegal drugs, which can be subject to errors and sampling bias.