What Minnesota can learn from legalization in other states

The marijuana bill making its way through the Legislature is in many ways a uniquely Minnesotan approach to legalization. But the experience of other states looms large in the debate, with both supporters and opponents citing outcomes elsewhere as evidence in favor of their position.

With nearly a decade of legal weed experience behind them, Colorado and Washington provide the most data for comparison. And in both states, the most striking finding is how little has changed overall: Legalization proved to be neither the universal panacea envisioned by some proponents, nor the disaster many opponents warned about. 

Below, we’ve collected data on some of the outcomes that have come up repeatedly in the marijuana debate in Minnesota. Many of them — like road safety and mental health — are complicated social phenomena driven by many different factors, making it difficult for even the most careful researchers to make definitive claims about legalization’s effects. 

Nevertheless, some trends are emerging.

Adult marijuana use increased

Unsurprisingly the data shows that if you legalize a drug for adult use, more adults are going to use it. Data from federal surveys, for instance, shows that marijuana use among adults in both Colorado and Washington increased in the years following legalization, with close to a quarter of respondents in both states now saying they use pot at least once per year.

It’s worth pointing out that use in those states, as well as the U.S. as a whole, was on the rise even prior to legalization. But there’s little doubt that legalization has accelerated that trend.

Teens are staying away from it

On the other hand, the data shows no increase in use among teenagers in states that have legalized. This was somewhat unexpected but is decidedly good news, as teens’ developing brains are at more risk of harm from marijuana (or any other drug, for that matter).

In fact, marijuana use is growing fastest not among young adults, but older ones. In Colorado for instance, use among seniors has tripled since legalization.

More little kids are finding mom and dad’s gummies

There have been some impacts on younger cohorts, however. Calls to poison control centers about kids accidentally getting exposed to marijuana are increasing. In Colorado, the annual number of such calls for kids under the age of 5 rose from the single digits in 2009 to more than 100 in 2021.

While the numbers aren’t large in absolute terms, the exposures can be bad enough to send kids to the hospital. Nationally about one-fifth of the children involved in these calls had symptoms serious enough to warrant a hospital visit. The problem has already arisen in Minnesota, which made THC edibles legal last year. The Rochester Post-Bulletin reported recently that 94 children under age 6 were reported to have accidentally ingested edibles in 2022, an increase of 334% over the previous year. Concern over edible exposures has prompted many states to tighten their regulations for edible products.

Data on traffic safety is mixed

This is one of opponents’ major concerns about legalization. One number that gets cited frequently is from a report by the federal drug task force overseeing Colorado, which states that “traffic deaths where drivers tested positive for marijuana increased 138%.” 

This number is technically correct, but misleading. As the Colorado Division of Criminal Justice noted in a report summarizing the effects of legalization, the presence of cannabis compounds in a person’s blood doesn’t necessarily indicate impairment: Some of those chemicals remain detectable long after an individual has used marijuana, and the primary intoxicating chemical (Delta-9 THC) can be detected in some users after a week or more of sobriety.

Higher rates of marijuana use are going to lead to more detection of marijuana in fatal car accidents, regardless of whether the drivers involved in those accidents were high at the time of the crash.

Research using more careful methods to examine traffic fatalities has yielded far more modest findings. The Insurance Institute for Highway Safety, for instance, found that car crash injuries increased by 6% and fatalities by 4% following legalization. Another recent study found “no statistically significant change” in traffic fatalities in legal states, while yet another study found evidence for a modest increase in fatal crashes following the opening of commercial dispensaries.

No change in crime

Despite overheated claims about links between marijuana use and violent crime, the actual evidence shows that legalization has virtually no impact on crime rates, and if anything it might reduce certain types of it.

One early study found that legalization in Colorado may have led to lower rates of property crime, theft and assault in the mountain west, while another suggested legalization may have lowered the incidence of rape and property crime in Washington. Two other studies found no effect at all on crime rates, with the most recent noting curtly that “increased crime rates should not be a primary concern as more states move to adopt recreational marijuana use legislation.”

Legalization does, however, dramatically reduce the amount of law enforcement time and resources devoted to policing marijuana use. In Colorado, for instance, marijuana arrests fell by 68% following legalization. Racial disparities in marijuana policing, however, remained.

Some evidence for mental health impacts

Another primary area of concern is mental health. At last week’s House hearing, for instance, lawmakers heard from White Bear Lake parents who said their son’s suicide death was caused by marijuana-induced psychosis. 

Some research has suggested a link between cannabis use and suicidal ideation among young adults. Another study found that the suicide rate among teens and young adults increased following legalization in Washington, but not in Colorado. Neither study was able to say that marijuana use or legalization definitively caused the observed increases in suicidality, however.

Other research has suggested that legalization in Colorado led to an increase in emergency room visits for psychotic episodes. Colorado’s Division of Criminal Justice, meanwhile, reported that suicide rates in the state have been “stable” since legalization.

Jobs and economy

Some legalization opponents worry that broader access to marijuana will cause workers to become lazy and unmotivated, with potentially negative impacts on the economy. But there’s no real-world evidence for that claim. One of the more comprehensive studies to date, for instance, found that the only tangible effect of marijuana legalization on the labor market was a modest increase in agricultural employment, “consistent with the opening of a new licit market.”