Study Reveals What Happens When Drugs Are Legalized


Ben Taub

Freelance Writer

clockMay 18 2021, 14:45 UTC
Cannabis legalization

A number of US states have legalized recreational cannabis. Image: Strela Studio/

Drug law reform has become a major topic of debate in recent years, with a growing number of states and nations choosing to decriminalize or even legalize certain substances following decades of prohibition. The pace of change has caused a split in opinions, with some praising governments for being bold while others have expressed concern at the potential harms that could result from these liberal policies. Yet as the hard data begins to trickle in, scientists are now gaining a more concrete understanding of how policy changes affect drug use and drug markets.

A new study in the journal Addiction, for example, reveals how the legalization of recreational cannabis has altered the nature of various illegal drug markets in the US. So far, 15 states plus the District of Columbia have implemented recreational cannabis laws (RCLs), resulting in massive changes in the amount and potency of other illicit drugs circulating on the streets.


"Our exploratory findings suggest that markets for illegal drugs may not be independent of legal cannabis market regulation,” explained lead author Dr. Angélica Meinhofer in a statement. “As more states move towards legalization and additional post-RCL implementation data become available, we'll need to do more research to determine whether recreational cannabis laws cause those changes in the illegal market and what happens in the long-term."

To conduct their research, the authors gathered data collected by the Drug Enforcement Agency concerning the price and concentration of illegal cannabis, heroin, cocaine, amphetamine and other opioids in states with RCLs. They also used information from a crowdsourcing tool called Price Of Weed in order to ascertain how the cost of illegally-bought cannabis has changed in these states since these laws were passed.

Results indicate that the price of illegal cannabis has dropped by 9.2 percent in states with RCLs, with a decrease of 19.5 percent for “low-quality” illegal cannabis. In such states, weed can be bought legally only from licensed retailers, such as dispensaries, and any cannabis sold by unlicensed dealers remains illegal.

According to the study authors, this price drop is likely down to the fact that cannabis can now be produced domestically, which means less needs to be imported from foreign cartels. The hit taken by these illegal trafficking organizations may ultimately have caused them to exit the market altogether, resulting in a decrease in supply of other illicit substances.


As such, the researchers found that law enforcement seizures of illegal opioids have dropped by more than 50 percent in states with RCLs. However, the potency of street heroin has increased by 54 percent, while prices have jumped by 64 percent.

Interestingly, the researchers found no significant changes in the price, availability of potency of cocaine or methamphetamine in these states. Regardless, they conclude that the full public health impact of drug law reform can only be understood by analyzing the connection between legal and illegal drug markets.

A range of other unexpected consequences are also becoming evident in the state of Oregon, which decriminalized all drugs earlier this year. In particular, certain Native American communities have expressed concern that this policy change could threaten their attempts to conserve the psychoactive Peyote cactus, which is central to some indigenous cultures but also popular among psychedelics users.

With the plant becoming increasingly scarce, the Indigenous Peyote Conservation Communication Committee (IPCCC) has urged authorities to exclude Peyote from decriminalization measures in Oregon, in order to protect it from extinction.




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