What have we learned about the arguments for and against legalized Marijuana in the past 10 years?

When Colorado voters legalized use, possession and sale of small amounts of marijuana 10 years ago, they faced a lot of unknowns.

“A great experiment,” is what legalization skeptic-turned-believer John Hickenlooper, who was the state’s governor a decade ago and is now a U.S. senator, has called it.

But how has that experiment turned out? Have the promises been kept? Have the fears of legalization opponents been borne out?When the blue book, the nonpartisan voter guide, was distributed to voters in 2012, it contained three arguments for legalization and three arguments against. Here we take those arguments directly from the blue book and break them down to see what happened and what didn’t.

The Arguments

Arguments For

1) Current state policies that criminalize marijuana fail to prevent its use and availability and have contributed to an underground market. By creating a framework for marijuana to be legal, taxed, and regulated under state law, Amendment 64 provides a new direction for the state.

2) It is preferable for adults who choose to use marijuana to grow it themselves or purchase it from licensed businesses that are required to follow health and safety standards, rather than purchasing products of unknown origin from individuals involved in the underground market. A regulated market will provide a safer environment for adults who purchase marijuana and, by requiring age verification, will restrict underage access to marijuana. The measure will also add sales tax revenue and may add job opportunities to the state economy.

3) The adoption of Amendment 64 will send a message to the federal government and other states that marijuana should be legal and regulated and that industrial hemp should be treated differently than marijuana. Adults should have the choice to use marijuana, just as they have that choice with other substances such as alcohol and tobacco. Further, because of its commercial applications in fuel, building materials, clothing, and food, industrial hemp should be allowed to be grown, processed, and sold domestically.

Arguments Against

1) Even if Amendment 64 is adopted, the possession, manufacture, and sale of marijuana remain illegal under current federal law, so the adoption of the measure may expose Colorado consumers, businesses, and governments to federal criminal charges and other risks. People who invest time and money to open marijuana establishments have no protections against federal seizure of their money and property. Because federal banking laws do not allow banks to accept the proceeds of, or loan money for, activities that are illegal under federal law, marijuana businesses will likely need to be cash-only businesses. In addition, enhanced federal scrutiny and competition from retail marijuana establishments could jeopardize the existing medical marijuana system. The efforts of individuals who feel that marijuana use should be legal for all adults are more appropriately directed at changing federal law.

2) Marijuana impairs users’ coordination and reasoning and can lead to addiction. Allowing state-regulated stores to sell marijuana will make it more accessible, which is likely to increase use and may give the impression that there are no health risks or negative consequences to marijuana use. Greater accessibility and acceptance of marijuana may increase the number of children and young adults who use the drug, which, due to their ongoing brain development, may be especially dangerous. Furthermore, because more people are likely to use marijuana, the number of those who drive while under the influence of or while impaired by the drug may increase.

3) A ballot measure cannot direct any vote cast by a legislator. Amendment 64 asks voters to approve a regulatory structure for the sale of marijuana, but does not specify critical details about what the regulations will entail. Furthermore, because the provisions of Amendment 64 will be in the state constitution and not in the state statutes, where most other business regulations appear, there may be unintended consequences that cannot be easily remedied. For example, the state legislature cannot adjust the deadlines, fees, and other details regarding the implementation of the measure. In addition, by constitutionally permitting marijuana use, the measure, despite its stated intent, could create conflicts with existing employment, housing, and other laws and policies that ban the use of illegal drugs.

Here’s how these issues have played out so far:

Did marijuana legalization end the black market?

Cannabis legalization did not eliminate the marijuana black market in the state and in some ways created a new opportunity for the black market to flourish. This is in part because, with marijuana remaining illegal in other states, Colorado became an attractive place for black-market growers to set up shop, sometimes using Colorado’s cannabis industry as cover for their operations.

A report last year by the Colorado Department of Public Safety found that “the amount of marijuana diverted out of Colorado is difficult to estimate” because only a small percentage of it is caught and because there is no central database to track it. Using a database maintained by the Drug Enforcement Administration’s El Paso Intelligence Center, the report found that seizures of marijuana coming from Colorado jumped significantly in the years following 2014, when Colorado’s first recreational cannabis shops opened.

There were 286 seizures in 2012. By 2015, there were 768 seizures. The numbers have declined since then and, in 2019, the figure hit 266 seizures, below the 2012 benchmark.

Investigators load marijuana plants onto a Colorado National Guard truck outside a suspected illegal grow operation in north Denver early Thursday, April 14, 2016. (AP Photo/P. Solomon Banda)

Annual reports published by the Rocky Mountain High-Intensity Drug Trafficking Area, a law enforcement group, often highlight the continued presence of the marijuana black market in Colorado. Last year’s report noted that 2019 saw the largest marijuana bust in the history of Colorado, involving 250 homes and businesses. 

But even legalization opponents believe that Colorado won’t remain a national black-market center forever. The same RMHIDTA report cites a 2021 study that found cannabis users perceive legal cannabis to be higher-quality and safer compared to black-market marijuana. But higher prices in the legal market suggest that the black market could persist in some form.

“More states are going to legalize it and at least the exportation problems will go away,” John Suthers, the former Colorado attorney general and current mayor of Colorado Springs, said. “I think there’s still going to be a pretty healthy black market, because they can undersell the regulated market.”

Did marijuana legalization restrict teen access to cannabis?

It’s difficult to track something that is by definition illicit, but the answer here appears to be yes.

Every two years, Colorado conducts the Healthy Kids Colorado Survey, which polls tens of thousands of middle and high schoolers across the state — the most recent, in 2021, polled more than 50,000 students. The survey is seen as the gold standard for analyzing behavior trends of Colorado kids.

One question asked each year is whether students believe “it would be sort of easy or very easy to get marijuana if they wanted.” In 2021, 40.3% of high school students answered yes to that question. In 2013, one year prior to recreational stores opening, the percentage was 54.9%. It peaked in 2015 at 55.7% and has been declining since.The Colorado Marijuana Enforcement Division, the regulator of cannabis shops in the state, also conducts undercover compliance checks to ensure stores are asking for ID and not selling to minors. According to an August bulletin from the agency, underage operatives had at that time conducted more than 190 compliance checks for the year. Four stores made sales to a minor in those checks, meaning there was a 98% compliance rate.

Did marijuana legalization boost tax revenue and the economy?

In direct terms, yes.

State-licensed marijuana sales in Colorado have totaled more than $13.4 billion since 2014, according to the Colorado Department of Revenue. That has generated nearly $2.3 billion in tax revenue.

There are currently more than 600 retail marijuana stores in the state — that’s more than the number of Starbucks locations.

A report released earlier this year by the cannabis information website Leafly found that more than 35,000 people were employed in the state’s marijuana industry, making it the second-biggest cannabis industry in the country, behind California’s. A more recent Leafly report concludes that the cannabis industry nationwide supports more than 400,000 jobs.

Supporters of legalization will argue that this doesn’t capture the total economic impact of the industry — encompassing all the vendors who provide services to the industry or benefit from its footprint. Opponents of legalization will say that these figures don’t factor in the harms that legalization has caused and the economic drain of those.

Did marijuana legalization send a message to the federal government?

If it did, the feds aren’t listening. But 18 additional states plus the District of Columbia and two U.S. territories have now passed legalization laws.

During the wave of state cannabis policy changes that began in Colorado and Washington state, Congress and the White House have largely not budged. There has been no serious legislation at the federal level to legalize cannabis. Colorado U.S. Rep. Ed Perlmutter’s frequent attempts to pass a law protecting banking access to the marijuana industry has gone nowhere, very slowly. (Though Hickenlooper recently said he is optimistic it might be passed this year.)

President Joe Biden recently granted pardons for low-level federal marijuana offenses and also vowed to examine whether marijuana’s scheduling in the Controlled Substances Act should be changed. Pro-legalization activists saw this as a move that could lead the way to federal legalization or, at least, decriminalization. But anti-legalization activists, like Kevin Sabet, saw it as something different — a way for the federal government to reassert the evidence for keeping marijuana illegal.

“I don’t think it’s going to get the outcome the legalizers want,” Sabet said. “And the feds are going to be able to say, ‘Listen, we went through the scientific process; this is what it is.’”

Did marijuana legalization lead to an industrial hemp revolution?

Yes, but not in the way that was envisioned.

Amendment 64, Colorado’s legalization measure, talked about hemp in terms of “fuel, building materials, clothing, and food.” Likewise, when Congress passed the 2018 farm bill, which contained a provision legalizing hemp, the focus was on its more industrial uses.

But that’s not where the hemp industry has flourished most. The farm bill defined hemp as any cannabis plant containing less than 0.3% THC — THC being the intoxicating substance in cannabis. There was no cap placed on other kinds of cannabis substances, called cannabinoids. This has led to a flood of products containing the cannabinoid CBD in grocery stores and other shops across the country. But it has also had a really unexpected consequence.

That tiny percentage of THC allowed in hemp opened the door for crafty entrepreneurs to use hemp crops to extract THC and put it into products that they argue are legal and not subject to state marijuana regulations. Similarly, hemp growers are extracting CBD and using a chemical process to convert it into a different form of THC. This has given rise to the “intoxicating hemp” industry.State regulators are pushing back. A bill passed last year in Colorado created a task force that will propose ideas for regulating intoxicating hemp products.

Did marijuana legalization lead to a federal crackdown?

No, at least not for those following the rules.

More than six months after Colorado voters approved legalization, the federal government finally responded by issuing what is known as the “Cole memo.” It’s named after the deputy U.S. attorney general who authored it, James Cole. The memo said the federal government would not block marijuana legalization in Colorado and Washington state, so long as cannabis businesses played by the rules and didn’t do things like sell to kids, traffic marijuana to neighboring states or act in cahoots with criminal gangs.

There have been a handful of federal busts of Colorado marijuana businesses since then. In those instances, the federal government will often declare that the stores were operating outside the state law, though those associated with the stores will say they believed they were in compliance with state law.

Colorado cannabis businesses have also faced scrutiny from the Internal Revenue Service. But no government employees have been criminally charged for carrying out their official duties overseeing marijuana legalization.

It should be noted that former U.S. Attorney General Jeff Sessions rescinded the Cole memo early in the Trump administration. But the decision didn’t significantly change the federal government’s enforcement approach.

Are Colorado marijuana businesses cash-only?

Yes. No. Maybe?

Cannabis businesses still struggle with access to the banking system. In the early days following legalization, it was a given: Marijuana shops were cash-only. This led to bulked-up security at stores and high-stakes tax payments.

Since then, the situation has mellowed a bit. Federal guidance issued in 2014 provided a roadmap for how banks could work with marijuana-related businesses without getting in trouble, and the number of banks providing services to the marijuana industry has increased since then.

It can still be spotty, though, as to whether shops will take plastic. Some accept debit cards. Many have ATMs on-site to facilitate cash transactions.

Did marijuana legalization hurt the medical marijuana system?

Colorado’s medical marijuana system is still alive and thriving, but legalization did appear to diminish its scale.

When voters passed legalization in 2012, there were about 107,000 registered medical marijuana patients in the state. That number peaked in late-2014 at nearly 120,000 patients.

Today, there are around 73,000 registered medical marijuana patients. About 79% of those list severe pain as a qualifying condition. Nearly 21% of them list a relatively new reason to the slate of qualifying conditions: using cannabis in lieu of opioids.

The number of registered caregivers — people designated to grow cannabis for a medical marijuana patient — has been declining. There are still lots of licensed medical marijuana shops in the state — roughly 400.

Amendment 64 opened cannabis sales to anyone 21 and older in the state. Medical marijuana patients, meanwhile, can be younger and can purchase slightly more at one time.

Did marijuana legalization cause more cannabis use among adults?

Demographic changes in the population make it difficult to be certain whether changes in usage patterns are the result of legalization. But the answer here appears to be that more adults are using marijuana in Colorado — and using it more frequently — than did prior to legalization.

The Colorado Department of Public Health and Environment produces the Behavioral Risk Factor Surveillance System, which every year polls Coloradans about their health behaviors. In 2014, when it asked adults about cannabis use, it found that 13.4% said they had used marijuana at least once in the prior 30 days. In 2021, that figure was up to 19%, where it has been for about the past three years.

The number of people reporting daily or near-daily marijuana use has also increased. In 2021, 52% of people who said they had used marijuana in the previous 30 days said they had been daily or near-daily consumers during that period. In 2014, that percentage was 44%.

It’s possible that an influx of people moving to Colorado after legalization could nudge these numbers upward, and it is also possible that people became more comfortable being honest about their usage in the past decade, too.To account for some of these problems, a recent study looked at data on twins and found that a twin living in a legal state, on average, reports using marijuana more frequently than their co-twin living in a state where recreational marijuana use is illegal. To the study authors, this provides solid evidence that legalization likely leads to higher rates of use among adults.

Did marijuana legalization lead to higher teen use?

Based on the best available data, the number of kids using marijuana has not increased.

Colorado health officials conduct the Healthy Kids Colorado Survey every two years. It is seen as a gold standard for assessing youth behavior trends in the state — the most recent version, in 2021, polled more than 50,000 middle and high school students.

After recreational cannabis stores opened in Colorado in 2014, teen usage rates measured in the survey remained statistically flat. That changed last year, when the survey found a statistically significant decrease in marijuana use among high school students. In that survey, 13.3% of high schoolers and 3% of middle schoolers reported using marijuana at least once in the previous 30 days. In 2015, the year after stores opened, those figures were 21.2% and 4.4%, respectively.

Numbers for students who have reported ever using cannabis also declined — 26.1% of high school students and 5.2% of middle school students said they had. Today’s high school students were in elementary school when voters legalized marijuana in Colorado. But the percentage of high school students today who say they first used cannabis before the age of 13 — 5% — is lower than it was in 2011, when the Healthy Kids Colorado Survey reported the figure at 9%.Among kids who did report using marijuana in the previous 30 days, the rate of those engaging in the heaviest use — as in 40 or more times — declined in 2021, compared with 2019 and is below rates seen in the 2013 survey.

Southbound Interstate 25 traffic lanes bog down to a crawl at the interchange with Interstate 70 just north of downtown Denver, on July 11, 2019. (AP Photo/David Zalubowski)

Did marijuana legalization increase stoned driving?

A report last year by the Colorado Department of Public Safety found that citations issued by Colorado State Patrol troopers for marijuana-impaired driving offenses have increased since legalization, but urged caution on the analysis.

“It is difficult to gauge the scope of DUID offenses for a number of reasons,” the report stated. (DUID stands for driving under the influence of drugs.)

The report found that citations for impaired driving where marijuana was perceived as being at least one of the substances involved increased 120% from 2014 to 2020. The biggest jump occurred in citations where both marijuana and alcohol were perceived to be the substances involved. Citations where marijuana was the only suspected intoxicant increased 16%, to 417 in 2020, up from 359 in 2014.

But the report notes that the number of law enforcement officers trained to recognize drug impairment also increased during that time, possibly leading to more citations for drug-impaired driving.

Conviction rates for cases of marijuana-impaired driving also vary significantly. The report found that drivers who tested positive for only THC and the THC level was above 5 nanograms per milliliter of blood — a level that creates a “permissible inference” of impairment in Colorado law — were convicted 87% of the time. Drivers who tested positive for only THC at below 5 ng were convicted only 35% of the time. Roughly half of drivers in 2018 who were initially believed to be marijuana-impaired had THC levels below 5 ng, according to the report.

Fatal traffic crashes involving marijuana-impaired drivers were flat.

Did marijuana legalization create conflicts with housing and employment laws?

Yes, but those were largely worked out through the court system.

From a very technical, legal perspective, Colorado voters didn’t really legalize marijuana when they approved Amendment 64. Voters legalized only certain, limited activities related to marijuana. There are still lots of things concerning marijuana possession and use that remain prohibited, and cannabis also remains illegal under federal law. For this reason, lots of rules around marijuana can still be enforced.

Employers, for instance, can still fire employees for using marijuana — even off the job. A bill introduced earlier this year at the state Capitol to change that failed in committee. Landlords can still prohibit tenants from using marijuana and can evict them if they violate that policy.

People on probation can be barred from using marijuana, but a bill passed in 2015 gave probationers the ability to use medical marijuana if they are a registered patient. 

It shows how, 10 years later, cannabis legalization in Colorado remains an evolving policy, an experiment still being run.