Marijuana legalization—whether you think of it as a health issue, a criminal matter, or a question of personal choice—is moving up on legislators’ agendas. If you haven’t yet had a chance to vote on marijuana legalization, you likely will in the next few years.
So far, 32 states and Washington DC allow the medical use of marijuana, 13 states have decriminalized (though not fully legalized) it, and a further 10 states and Washington DC have legalized it for recreational use.
Nearly four out of five students said they were either for legalizing marijuana or felt neutral about the issue, according to a recent Student Health 101 survey. Not sure where you stand? Take a look at what the experts have to say about both sides of the debate.
Proponents of legalizing marijuana for recreational use often cite the potential for a big economic boost—if marijuana were legal, it could be regulated and taxed, says Paul Armentano, deputy director of the National Organization for the Reform of Marijuana Laws (NORML). Between January 2014, when marijuana was first legalized in Colorado, and July 2017, the state made half a billion dollars in cannabis-related revenue.
Legalizing marijuana could also help reduce racial discrimination in the criminal justice system. A 2013 report by the American Civil Liberties Union found that “on average, a black person is 3.73 times more likely to be arrested for marijuana possession than a white person, even though blacks and whites use marijuana at similar rates.”
Other issues surrounding legalizing marijuana are more hotly debated.
The case against legalization
“Marijuana use impairs a person’s reaction time, their ability to stay in their lane, and their judgment of distance,” says Dr. Kevin Sabet, president of anti-marijuana advocacy group Smart Approaches to Marijuana (SAM). “Legalization is making our roads—already dangerous due to substances [that are] currently legal—even more dangerous.”
The case for legalization
Driving under the influence, whether that’s of marijuana or another substance like alcohol, is already illegal, says Armentano. “Laws legalizing and regulating the adult use of cannabis in private do not change this fact.”
What the research says
A 2018 report by the Insurance Institute for Highway Safety found that car accidents had increased by six percent in four states that had legalized marijuana for recreational use. More research is needed to determine whether marijuana legalization has to do with this increase.
The case against legalization
It’s not shocking to hear that smoking pot is associated with academic issues. In a 2015 study, researchers followed more than 1,200 college students over eight years, tracking how their GPA and graduation outcomes stacked up against their marijuana use and found that—you guessed it—students who smoked pot had lower GPAs. (The issue, they found, is tied to skipping class—students who smoked were more likely to skip and therefore got poorer grades.)
The case for legalization
This is why marijuana should be legalized—and thereby regulated, says Armentano. Regulating the sale of marijuana means governments could regulate the process by which it’s produced and sold safely to adults, he says, better restricting sales to minors at the same time. That, “coupled with a legal environment that fosters open, honest dialogue between parents and children about cannabis’s potential harms, best reduces the risks associated with the plant’s use or abuse,” he says.
Reminder: Even in states where it’s allowed, the legal age to use marijuana is 21.
The case against legalization
Some research suggests marijuana use might specifically be linked to the opioid crisis. Cannabis use is associated with an increased risk of “nonmedical prescription opioid use,” according to a 2018 study published in the American Journal of Psychiatry. “At a time when our country is literally in the midst of an addiction epidemic, the last thing we need to be doing is normalizing the use of another addictive substance,” Dr. Sabet says.
The case for legalization
While marijuana can be addictive, most people do not become dependent on it, Armentano says. “Rates of problematic cannabis use have fallen sharply in the era of liberalization,” he says, citing a 2018 study published in Drug and Alcohol Dependence, which found rates of marijuana dependence fell nearly 40 percent among adults between 2002 and 2016. “This is not to imply that cannabis is harmless or that we as a society should turn a blind eye to problematic use,” he says. “Such public health concerns are best addressed through regulation and education.”
And about opioid addiction? Emerging research, also published in 2018, suggests marijuana has the potential to help alleviate opioid withdrawal symptoms, reduce the likelihood of opioid misuse, and “decrease the likelihood of relapse” (Cannabis and Cannabinoid Research). As the authors note, there’s a lot more research to be done here.
At this point, it’s too difficult to say whether marijuana legalization is more likely to help or harm the opioid addiction crisis.
The possible health effects of regular marijuana use are still being researched and debated. Some risks have been fairly well documented, including:
Cough and chest infections
Regular marijuana smoking is associated with coughing and phlegm, bronchitis, and increased susceptibility to respiratory infections.
Heart and lung problems in some users
Marijuana use initially increases the heart rate and blood pressure. In most young, healthy users, the cardiovascular effects are not associated with serious health problems. Marijuana use is riskier for people with preexisting cardiovascular disease.
Mental health issues
Marijuana use has been linked to several mental health issues and psychiatric disorders, according to the National Institute on Drug Abuse. Studies have linked cannabis to depression, anxiety, and even schizophrenia—the latter of which can be made worse by smoking pot.
Potential health benefits
Researchers’ interest in marijuana goes far beyond using pot for pain relief. Marijuana interacts with human cells in diverse ways, offering the potential for a range of medical uses. Scientists are interested in the potential therapeutic effects of marijuana on glaucoma (an eye condition that can cause blindness), some cancers, autoimmune disease, inflammation, pain, seizures, gastrointestinal disorders, drug addiction, anxiety, and post-traumatic stress disorder, among other health conditions. In fact, last year, the Food and Drug Administration (FDA) made history by approving the first drug derived from cannabidiol (CBD), a chemical component in marijuana, to treat certain forms of epilepsy.
Beware the hype
Pressure to legalize medical marijuana has resulted in advocates exaggerating the health benefits. Marijuana has medical potential, but it is not a miracle drug. “A more balanced, science-based approach is desperately needed,” says the Society for Science-Based Medicine, which critically evaluates medical treatments and claims.
Researchers studying the health, behavioral, and developmental effects of marijuana use have to wrestle with various complicating factors. These factors can lead to mixed results and raise questions about the accuracy and relevance of the study findings. They include:
The effects of the drug are variable
The effects of marijuana depend on how the drug is used, how much is used and how often, who’s using it, and in what circumstances.
It’s hard to know what’s causing what
It can be difficult to filter out the effects of marijuana use from the effects of other substances, emotional health issues, and other factors.
Study participants may not be typical users
Studies may rely too heavily on users who are seeking treatment or whose struggles may be worse than average. This can introduce bias.
Older studies may be losing relevance
Most research has involved marijuana of lower potency than is generally used today, so the findings might understate the effects. That said, it’s not clear that higher potency contributes to greater use or worse outcomes.
The intense politics around marijuana legalization increase the likelihood that evidence will be misinterpreted, misrepresented, and biased.
Researchers’ limited access to the drug
Legal restrictions limit scientists’ access to marijuana, a barrier to conducting clinical trials of marijuana-based medications and other studies.
Nearly two-thirds (62 percent) of Americans support legalizing marijuana, according to a 2018 poll conducted by the Pew Research Center—a huge jump from 18 percent in 1991.
Student Health 101 asked college students to rank their concerns or hopes relating to marijuana legalization. Many students with opposing views were able to find common ground. Here’s what you said:
Students’ top reasons for supporting legalization:
- Medical treatments for disease and pain
- Cost savings in the “War on Drugs”
- Taxes on marijuana as an important source of revenue
The top concerns of students who supported legalization were:
- Risks of driving under the influence
- Tension between federal and state laws
Students’ top reasons for opposing legalization:
- Risks of driving under the influence
- The implied message to kids that marijuana use is safe
- Tension and confusion between federal and state laws and legal penalties
Students who opposed recreational legalization agreed that:
- Medical use makes sense
- The tax revenues could be helpful
Paul Armatano, deputy director, National Organization for the Reform of Marijuana Laws (NORML), Washington DC.
Kevin Sabet, PhD, president, Smart Approaches to Marijuana (SAM), Alexandria, Virginia.
American Civil Liberties Union. (2013 June). The war on marijuana in black and white. Retrieved from https://www.aclu.org/files/assets/aclu-thewaronmarijuana-rel2.pdf
Compton, R. P., & Berning, A. (2015, February 10). Drug and alcohol crash risk. National Academy of Sciences. Retrieved from https://trid.trb.org/view.aspx?id=1343066
Davenport, S. (2018). Falling rates of marijuana dependence among heavy users. Drug and Alcohol Dependence, 191, 52–55. doi: 10.1016/j.drugalcdep.2018.06.025
Drug facts: Marijuana. (n.d.). National Institute on Drug Abuse. Retrieved from http://www.drugabuse.gov/publications/drugfacts/marijuana
Fergusson, D. M., & Boden, J. M. (2008). Cannabis use and later life outcomes. Addiction, 103(6), 969–976; 977–968.
Gorski, D. (2014, July 7). Medical marijuana as the new herbalism. Science-Based Medicine. Retrieved from http://www.sciencebasedmedicine.org/medical-marijuana-as-the-new-herbalism-part-1-the-politics-of-weed-versus-science/
Gruber, A. J., Pope, H. G., Hudon, J. I., & Yurgelun-Todd, D. (2003). Attributes of long-term heavy cannabis users: A case-control study. Psychological Medicine, 38(8), 1415–1422.
Hall, W., & Degenhardt, L. (2009). Adverse health effects of non-medical cannabis use. Lancet, 374(9698): 1383–1391.
Hartig, H., & Geiger, J. (2018, October 8). About six-in-ten Americans support marijuana legalization. Pew Research Center. Retrieved from http://www.pewresearch.org/fact-tank/2018/10/08/americans-support-marijuana-legalization/
Karush, S. (2018, October 18). Status report: Legal pot. Insurance Institute for Highway Safety, 53, (6). Retrieved from https://www.iihs.org/externaldata/srdata/docs/sr5306.pdf
Lopez, G. (2018, November 14). 13 states have decriminalized—but not legalized—marijuana. Vox. Retrieved from https://www.vox.com/identities/2018/8/20/17938358/marijuana-legalization-decriminalization-states-map
Lopez, G. (2018, November 14). Marijuana is legal for medical purposes in 32 states. Vox. Retrieved from https://www.vox.com/identities/2018/8/20/17938366/medical-marijuana-legalization-states-map
Lopez, G. (2018, November 14). Marijuana has been legalized in 10 states and Washington DC. Vox. Retrieved from https://www.vox.com/identities/2018/8/20/17938336/marijuana-legalization-states-map
Macleod, J., Oakes, R., Copello, A., Crome, I., et al. (2004). Psychological and social sequelae of cannabis and other illicit drug use by young people: A systematic review of longitudinal, general population studies. Lancet, 363(9421), 1579–1588.
Mehmedic, Z., Chandra, S., Slade, D., Denham, H., et al. (2010). Potency trends of 9-THC and other cannabinoids in confiscated cannabis preparations from 1993 to 2008. Journal of Forensic Science, 55(5), 1209–1217.
Meier, M., Caspi, A., Ambler, A., Harrington, H., et al. (2012). Persistent cannabis users show neuropsychological decline from childhood to midlife. Proceedings of the National Academy of Sciences of the USA, 109(40), E2657–E2664.
National Institute on Drug Abuse. (n.d.). Is marijuana safe and effective as medicine? National Institutes of Health. Retrieved from https://www.drugabuse.gov/publications/research-reports/marijuana/marijuana-safe-effective-medicine
National Institute on Drug Abuse. (n.d.). Is there a link between marijuana use and psychiatric disorders? National Institutes of Health. Retrieved from https://www.drugabuse.gov/publications/research-reports/marijuana/there-link-between-marijuana-use-psychiatric-disorders
Olfson, M., Wall, M., Liu, S., & Blanco, C. (2018). Cannabis use and risk of prescription opioid use disorder in the United States. American Journal of Psychiatry, 175(1), 47–53. doi: 10.1176/appi.ajp.2017.17040413
Radhakrishnan, R., Wilkinson, S. T., & D’Souza, D.C. (2014). Gone to pot: A review of the association between cannabis and psychosis. Frontiers in Psychiatry, 5(54). doi: 10.3389/fpsyt.2014.00054
Richer, I., & Bergeron, J. (2009). Driving under the influence of cannabis: Links with dangerous driving, psychological predictors, and accident involvement. Accident Analysis and Prevention, 41(2), 299–307.
Silins, E., Horwood, J., Patton, G., Fergusson, D., et al. (2014 September). Young adult sequelae of adolescent cannabis use: An integrative analysis. The Lancet Psychiatry, 1(4), 286–293. doi: 10.1016/S2215-0366(14)70307-4
Student Health 101 survey, conducted November 2018.
US Food and Drug Administration. (2018, June 25). FDA approves first drug comprised of an active ingredient derived from marijuana to treat rare, severe forms of epilepsy. Retrieved from https://www.fda.gov/newsevents/newsroom/pressannouncements/ucm611046.htm
Touchberry, R. (2017, August 4). If you smoke a lot of pot, your grades can take a hit. USA Today. Retrieved from https://www.usatoday.com/story/college/2017/08/04/if-you-smoke-a-lot-of-pot-your-grades-can-take-a-hit/37434511/
Volkow, N. D., Baler, R. D., Compton, W. M., & Weiss, S. R. B. (2014). Adverse health effects of marijuana use. New England Journal of Medicine, 370, 2219–2227.
VS Strategies. (2017, July 19). Colorado exceeds $500 million in cannabis revenue since legalization. Retrieved from http://vsstrategies.com/wp-content/uploads/VSS-CO-MJ-Revenue-Report-July-2017.pdf
Wiese, B., & Wilson-Poe, A. R. (2018). Emerging evidence for cannabis’ role in opioid use disorder. Cannabis and Cannabinoid Research, 3(1), 179–189. doi: 10.1089/can.2018.0022