In 2012 John Larson, a retired high school math and science teacher, voted against I-502, the initiative that legalized marijuana in Washington. Yet last week Larson was one of the first government-licensed marijuana merchants to open a store in that state: Main Street Marijuana in Vancouver. "If people were dumb enough to vote it in, I'm all for it," he told The New York Times. "There's a demand, and I have a product."
Colorado Gov. John Hickenlooper also seems to have had a change of heart about marijuana. The former brewer, who opposed Amendment 64, his state's legalization initiative, is not about to become a budtender. But in a recent interview with Reuters, Hickenlooper conceded that the consequences of letting people grow, sell, and consume pot without risking arrest have not been as bad as he feared.
"It seems like the people that were smoking before are mainly the people that are smoking now," Hickenlooper said as Colorado marked six months of legal recreational sales at the end of June. "If that's the case, what that means is that we're not going to have more drugged driving, or driving while high. We're not going to have some of those problems. But we are going to have a system where we're actually regulating and taxing something, and keeping that money in the state of Colorado…and we're not supporting a corrupt system of gangsters."
Hickenlooper sounds cautiously optimistic, and there are good reasons for that. Possession and consumption of cannabis have been legal in Colorado and Washington since the end of 2012. In Colorado, so has home cultivation of up to six plants and noncommercial transfers of up to an ounce at a time. Since the beginning of this year, anyone 21 or older has been able to walk into a store in Colorado and walk out with a bag of buds, a vape pen loaded with cannabis oil, or a marijuana-infused snack. And for years in Washington as well as Colorado, such products have been readily available to anyone with a doctor's recommendation, which critics say is so easy to get that the system amounts to legalization in disguise. Despite all this pot tolerance, the sky has not fallen.
A study released yesterday by Colorado's Marijuana Enforcement Division supports Hickenlooper's impression that legalization has not had much of an effect on the prevalence of cannabis consumption. The authors, Miles Light and three other analysts at the Marijuana Policy Group, note that the percentages of Coloradans reporting past-month and past-year consumption of marijuana in the National Survey on Drug Use and Health (NSDUH) rose between 2002 and 2010, mirroring a national trend. But consumption fell a bit in Colorado after 2010 while continuing to rise in the rest of the country. That is striking because Colorado's medical marijuana industry began to take off in the second half of 2009 after the legal standing of dispensaries became more secure.
Another surprising finding is that marijuana use during this period was less common in Colorado than in the country as a whole. Based on NSDUH data from 2010 and 2011, 12 percent of Coloradans 21 or older were past-year users, compared to a national figure of 16 percent. But among those past-year users, daily use was more common in Colorado: 23 percent of them reported consuming marijuana 26 to 31 times a month, compared to a national rate of 17 percent. It's not clear to what extent Colorado's medical marijuana system is responsible for this difference in patterns of use.
More-recent NSDUH numbers for Colorado are not available yet. But Light and his colleagues, in estimating total marijuana consumption for 2014, assume that prevalence rates remain about the same this year, despite broader legalization. "We do not include an additional prevalence increase factor," they explain, "because the NSDUH user population for Colorado was flat between 2009/2010 and 2010/2011." That assumption may prove to be mistaken, and in any case prevalence may rise as the recreational market develops and prices fall. But so far it looks like Hickenlooper is right: Legalization has not resulted in a lot of new pot smokers.
The experience with medical marijuana is also instructive when it comes to underage consumption. Studies that compare states with medical marijuana laws to other states do not find much evidence that allowing patients to use cannabis for symptom relief drives up recreational use by teenagers. In the Youth Risk Behavior Survey, the share of Colorado high school students reporting past-month marijuana use fell by 11 percent between 2009 and 2011. (Nationwide that number rose by 11 percent during the same period.) Recreational sales may result in more diversion to minors than medical sales do, although legal retailers card all customers to make sure they are 21 or older, something black-market dealers do not have much incentive to do. Hickenlooper worried aloud about underage consumption in the Reuters interview. But when he was asked if there is "any evidence that it's easier for underage kids to get marijuana than six months ago," he replied: "No, we haven't seen that….One of the reasons so many people voted to legalize it was [that] it's been pretty easy to get it for decades."
What about drugged driving, another concern mentioned by Hickenlooper? A study reported in the journal Drug and Alcohol Dependence last April found that "the proportion of marijuana-positive drivers involved in fatal motor vehicle crashes in Colorado has increased dramatically since the commercialization of medical marijuana in the middle of 2009." Or as the headline over a University of Colorado at Denver press release put it, "Marijuana use [has been] involved in more fatal accidents since commercialization of medical marijuana." The implication is that easier availability of marijuana in Colorado has led to an increase in traffic fatalities. But as with a similar analysis of data from six states that was published by the American Journal of Epidemiology in January, that is not what the study shows.
Using data from the federal government's Fatality Analysis Reporting System, pharmacologist Stacy Salomonsen-Sautel and her co-authors found that the proportion of fatal crashes involving "marijuana-positive drivers" was 4.5 percent in the first six months of 1994, 5.9 percent in the first six months of 2009, and 10 percent at the end of 2011. The upward trend accelerated after Colorado regulators rejected restrictions on medical marijuana in July 2009, and there was no similar increase in the 34 states that at the time did not have medical marijuana laws. Meanwhile, the proportion of fatal accidents in which drivers tested positive for alcohol remained about the same.
Do these data mean that legalizing marijuana for medical or recreational use results in more blood on the highways? No. What Salomonsen-Sautel et al. call "marijuana-positive drivers" actually tested positive for metabolites that linger in blood and urine long after the drug's effects wear off. "THC metabolites are detectable in an individual's blood or urine for several days and sometimes weeks for heavy marijuana users," the authors note toward the end of the article. Hence a "marijuana-positive" result does not indicate the driver was under the influence of marijuana at the time of the accident, let alone that marijuana was a factor in the crash. "This study cannot determine cause and effect relationships, such as whether marijuana-positive drivers contributed to or caused the fatal motor vehicle crashes," Salomonsen-Sautel et al. concede. "Colorado may have an increased number of drivers, in general, who were using marijuana, not just an increase in the proportion who were involved in fatal motor vehicle crashes….The primary result of this study may simply reflect a general increase in marijuana use during this same time period in Colorado." (Salomonsen-Sautel et al. assume that marijuana consumption continued rising in Colorado after 2010, although the NSDUH numbers suggest otherwise.)
Another reason to doubt that greater tolerance of marijuana boosts traffic deaths: "There was a decreasing trend in fatal motor vehicle crashes in Colorado since 2004." There was a similar decline in the 34 comparison states, so it does not look like readier access to marijuana has interfered with this welcome trend. In fact, there is some evidence that it has on balance reduced traffic fatalities by encouraging the substitution of marijuana for alcohol, which has a more dramatic effect on driving ability.
A recent working paper from the National Bureau of Economic Research casts some doubt on that hypothesis, finding that medical marijuana laws are associated with a 6-to-9-percent increase in the frequency of binge drinking among residents 21 or older. It is too early to say whether legalizing marijuana for recreational use will have a noticeable impact, whether positive or negative, on accident trends in Colorado or Washington. But for what it's worth, fatal crashes in Colorado, after rising from 2011 to 2012, fell slightly (from 434 to 428) between 2012 and 2013. In Washington fatal crashes rose slightly (from 403 to 405) between 2012 and 2013.
Hickenlooper did not mention crime rates, but some opponents of legalization warned that cash-heavy cannabusinesses would invite robberies, leading to an increase in violence. Instead the frequency of burglaries and robberies at dispensaries has declined since they began serving recreational consumers in January.FBI data indicate that the overall crime rate in Denver, the center of Colorado's marijuana industry, was 10 percent lower in the first five months of this year than in the same period of 2013.
Although the prospect of more money for the government to spend has always struck me as a pretty weak argument for legalization, Hickenlooper is happy to have tax revenue from the newly legal marijuana industry. So far there has not been much: just $15.3 million from the recreational sector in the first five months of 2014 ($23.6 million if you include medical sales), although monthly revenue rose steadily during that period. The economic activity associated with the new industry, including not just marijuana sales but various ancillary goods and services, is bound to be much more significant than the tax revenue. And although Hickenlooper says he does not want Colorado to be known for its cannabis, legalization (along with abundant snow) may have something to do with the record numbers of tourists the state is seeing. It seems clear, in any case, that legalization has not hurt Colorado's economy, which Hickenlooper accurately describes as "thriving."
Another benefit of legalization that can be measured in money is law enforcement savings, which various sources put somewhere between $12 million and $60 million a year in Colorado. Those estimates do not include the human costs associated with treating people like criminals for growing, selling, and consuming an arbitrarily proscribed plant. Prior to legalization police in Colorado were arresting 10,000 pot smokers a year. Today those criminals are customers of legitimate businesses, which are replacing the "corrupt system of gangsters" decried by Hickenlooper.
This article originally appeared at Forbes.