Has the legalization of medical marijuana increased the use of the drug by teens? Well, according to a provocative new study by economists at the University of Colorado Denver, the answer appears to be a resounding: "no."

"There is anecdotal evidence that medical marijuana is finding its way into the hands of teenagers, but there's no statistical evidence that legalization increases the probability of use," Daniel I. Rees, an economics professor at the University of Colorado Denver who worked on the study, said in a written statement.

In the wake of the release of this study, we spoke with Mason Tvert, co-director of Regulate Marijuana Like Alcohol, the marijuana advocacy group behind Colorado's Amendment 64, to shed some further light on the issue of marijuana legalization. If teen use has not gone up with increased availability, perhaps other ideas about pot use are also misunderstood?

Amendment 64 seeks to legalize marijuana for recreational use for adults and will appear on Colorado ballots this November. This will be the second time Coloradans will vote on recreational pot legislation -- state voters considered and rejected a similar recreational pot legalization initiative in 2006.

But it's not without its opponents. The recently launched "No on 64" campaign from Smart Colorado, led by former U.S. Senate candiate, current Weld County District Attorney and former marijuana legalization supporter, Ken Buck seeks to stop the passage of this ballot measure. And "No on 64" has four main tenets to their reasoning to why marijuana prohibition should continue.

Tvert took a look at Smart Colorado's "No on 64" four main talking points and gave a detailed and frank rebuttal about each. First, read "No on 64's" main talking point and then Tvert's response below that.

1. No on 64 says marijuana harms our children, via their website:

Marijuana is an addictive drug. For children and young adults, smoking marijuana permanently affects brain development, impairs learning ability and contributes to depression. Adolescents are more likely than adults to develop problems with marijuana abuse and addiction. Marijuana abuse accounts for 67 percent of the adolescents in substance-abuse treatment programs in the United States.

This would be more relevant if we were trying to make marijuana legal for adolescents, but we're not. The initiative applies specifically to adults 21 and older, and there will remain very stiff penalties for giving marijuana to minors (it's a felony in Colorado). Our current system of marijuana prohibition is the worst possible policy when it comes to keeping marijuana away from teens. For years they have reported that it is universally available despite its illegal status, and surveys show high school students can access marijuana easier than they can access alcohol or tobacco. If we want to control marijuana and keep it away from teens, we need to regulate it, put it behind the counter, and require proof of age to purchase it. Illegal drug dealers do not ask for ID, and they might also have other more harmful illegal products that teens and adults alike would never be exposed to in a regulated legal market.

According to the National Institute on Drug Abuse, marijuana is far less addictive than alcohol, tobacco, and in some ways caffeine (daily coffee drinkers know that missing a cup one day can result in physical withdrawal symptoms, whereas no physical withdrawal symptoms are associated with marijuana). This is not to say marijuana cannot become habit-forming and problematic for some; like many substances and behaviors, it can. But the potential for addiction and the harms associated with it pale in comparison to alcohol, which we clearly accept as a product that needs to remain legal and regulated in this country. By continuing to exaggerate the potential for addiction and other potential harms of marijuana, people like those with Smart Colorado are teaching young people not to trust what they hear about substances from authority figures. If they are told marijuana is incredibly addictive, some will inevitably try it, realize it is not remotely as addictive as they've been led to believe, and then assume they were lied to about other drugs that might actually be quite addictive.

The line about marijuana accounting for 67 percent of adolescents in substance-abuse treatment programs is perhaps one of the most intellectually dishonest arguments our opponents make. They tout this number yet fail to mention that the vast number of people in treatment for marijuana are forced into treatment via criminal justice referrals in order to avoid more severe criminal penalties. Since marijuana is the most accessible substance for young people, it comes as little surprise that it accounts for most drug-related offenses. These people are then told they can either go to treatment or face having a drug offense on their permanent criminal record. In some cases, they might even face time in jail or significant fines and other penalties. Over the past couple decades, the number of criminal justice referrals for marijuana has increased dramatically, thus there have been far more people referred to treatment than ever before, even if they do not have what would be defined as an addiction to marijuana.

2. No on 64 says marijuana conflicts with federal law, via their website:

Federal law will continue to ban the production, manufacture, transportation and distribution of marijuana in Colorado regardless of the voters’ decision on Amendment 64. The U.S. Supreme Court has already made it clear that federal law supersedes state law in this area. If Amendment 64 passes, Colorado’s recreational marijuana users will believe they are operating under the protection of Colorado law while, in reality, they would be subject to federal criminal prosecution.

Colorado voters approved a ballot initiative to repeal alcohol prohibition prior to the federal government repealing alcohol prohibition. They can do the same thing when it comes to marijuana. As we've seen with Colorado's experience with medical marijuana, it is possible to regulate the production and sales of marijuana at the state and local levels. Moreover, federal officials have made it abundantly clear that they do not enforce federal marijuana laws unless they involve extremely large quantities of marijuana being produced or distributed. If Amendment 64 passes, and federal officials have noted, adults 21 and older would no longer face the risk of arrest and prosecution for possessing and growing small amounts of marijuana. The federal government (DEA, US Attorneys, federal judges) do not handle these types of cases, and with no state or local laws to fall back on, marijuana will be legal. We certainly hope the federal government will not try to prevent our state from regulating and controlling this product once it becomes legal. I highly doubt our opponents are concerned about those individuals who are interested in getting involved in the regulated marijuana industry; regardless, those individuals are more than aware of the situation with the federal government, as medical marijuana industry members are today.

3. No on 64 says marijuana promotes increased use, via their website:

The more available a drug is, the more likely young people are to use the drug. Marijuana use among students already is on the rise. Suspensions for drug violations at Colorado’s public schools increased 45 percent over the past four years, expulsions for drug violations increased 35 percent, and referrals to police increased 17 percent. Among the most vulnerable group, ages 12 to 25, it is projected that the number of regular marijuana users will double.

This has actually proven to be not true. In Colorado, marijuana use among teens declined from 2009-2011, despite it increasing nationally. This was the two-year period in which medical marijuana and marijuana businesses proliferated in the state. It was also the period of time in which the state and localities finally began to regulate medical marijuana, which appears to have resulted in it becoming less available to teens.

The study just released by researchers at the University of Colorado Denver, University of Oregon, and Montana State University concluded:

While marijuana use by teens has been increasing since 2005, an analysis of data from 1993 through 2009 by economists at three universities has found no evidence to link the legalization of medical marijuana to increased use of the drug among high school students. "This result is important given that the federal government has recently intensified its efforts to close medical marijuana dispensaries," said Benjamin Hansen, assistant professor of economics at the University of Oregon who studies risky behaviors of adolescents and adults. "In fact, the data often showed a negative relationship between legalization and marijuana use."

The statistics that Smart Colorado are referring to are somewhat suspect. Note they say "drug violations" and not "marijuana;" that's because they have not broken been down by substance (ie. many might not be for marijuana, especially since prescription drugs are more popular than ever before among all age groups). Also, these reports are largely anecdotal and/or based on limited samples of students in limited geographic areas.

4. No on 64 says marijuana increases impaired driving, via their website:

According to recent statistics, between 2006 and 2010, more than 400 people were killed in Colorado from car crashes involving a driver who was on drugs. Smoking pot reduces coordination and impairs decision making which will lead to a significant increase in the number of crashes and deaths due to people who are driving under the influence of marijuana.

There is absolutely no evidence to suggest that accidents will increase if marijuana becomes legal for adults 21 and older. In fact, a report released by researchers at the University of Colorado Denver and other universities showed that, in states that have made medical marijuana legal, traffic fatalities have decreased. Notably, they hypothesize that this might be because alcohol use rates had dropped, which resulted in less drinking and driving, and thus fewer accidents.

Again, note Smart Colorado's peculiar use of "drugs" instead of "marijuana" in that first sentence. Not only does this include drivers who might have been zonked on painkillers or out of their minds on methamphetamine, it includes people who used marijuana and/or other drugs combined with illegal levels of alcohol.

Driving under the influence is a serious thing and we certainly do not believe anyone should be driving while intoxicated by marijuana or any substance. That is why our initiative explicitly states that the legislature shall maintain the ability to legislate on this issue how it sees fit. Currently, it is entirely illegal to drive under the influence of any amount of marijuana in Colorado. Moreover, prosecutors enjoy a 90-plus percent conviction rate for cases where drivers are suspected to be impaired by marijuana. The legislature has been considering strengthening DUI-marijuana laws in Colorado, and it can do so at any time before or after the initiative is adopted.

What do you think? Should marijuana be legalized or should prohibition persist? Let us know in your comments below.

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