Marijuana Legalization: Weighing the Pros and Cons

Introduction: The Legalization Debate

Support for marijuana legalization has increased in recent years, particularly since a number of states have legalized the drug, even though the substance remains officially prohibited at the federal level. The War on Drugs has had a disproportionate effect on many communities, and there is strong support for decriminalization at minimum, given the argument that enforcement has disproportionately and negatively impacted historically marginalized communities. There is also growing recognition of marijuana's use in palliative care, which has improved the drug's overall public perception. Nevertheless, questions remain about safety, and data on whether legalization produces a net positive or negative outcome for affected communities remains ambiguous.

Adolescent Use Trends After Legalization

In Colorado and Washington, "within Washington, the rate of perceived harmfulness of marijuana use decreased and the rate of past month use increased among eighth and 10th graders following" legalization, although the rate of acceptance among Washington 12th graders remained unchanged, as did rates in Colorado as a whole (Cerda 146). A 2018 study by the Colorado Department of Public Safety (CDPS) found that the proportion of high school students reporting marijuana use — either during their lifetime or within thirty days of responding to the survey — remained statistically unchanged from 2005 to 2017. In Washington, however, use among eighth and 10th graders increased by 2.0% between 2010 and 2012, and by 4.1% between 2012 and 2015, while marijuana use among the same demographic in states without legal recreational marijuana decreased by 1.3% and 0.9%, respectively, during those same periods (Cerda, et al.).

The reasons for increased marijuana use in Washington have been attributed to a variety of possible factors: the perception that the drug is less dangerous because it has been legalized; the possibility that students may more easily obtain it from adults or older teens; or the decrease in its black-market price following legalization. One difficulty, however, is the lack of comparative data, given that legalization has been relatively recent and limited to only a few states. The increase could possibly be due to Washington-specific factors not directly tied to legalization. Yet the lack of changed attitudes among 12th graders — compared to younger teens — does suggest that older adolescents may have already formed impressions of marijuana use before legalization took effect (Cerda, et al.).

The discrepancy between Washington and Colorado may stem from the fact that Colorado already had a well-established medical marijuana dispensary program, and that obtaining medical marijuana for recreational purposes — even before legalization — was common in the state, alongside a more permissive cultural attitude toward the drug. This points to yet another factor that may shape changes in usage patterns after legalization: the extent to which marijuana was already an accepted part of daily life for a state's residents.

Gateway Drug Concerns and Academic Outcomes

Beyond changes in perception among young people, states contemplating legalization must weigh several additional concerns. One frequently articulated concern, according to McCaffrey et al., is that greater acceptance of marijuana will likewise increase acceptance of other forms of drug use — in other words, the gateway drug hypothesis. However, while heavy marijuana use is correlated with high use of other illegal substances, other researchers have noted that this may be explained by shared underlying factors associated with youthful drug use more broadly, such as "less parental supervision, bad peer group, ADHD, general antisocial behavior, or other mental health problems" (McCaffrey 4).

A similar logic applies to academic outcomes. While poorer grades and absenteeism are positively correlated with high levels of marijuana use, these outcomes cannot be isolated from other factors associated with heavy drug consumption, including poor parental and peer relationships, other mental health issues, and environmental and social problems (McCaffrey, et al.). The existence of a correlation does not imply causation. In fact, heavy cigarette consumption is associated with similarly poor scholastic outcomes, even though cigarette smoking does not produce the cognitive impairment associated with drugs and alcohol (McCaffrey, et al.).

Conclusion: The Case for Caution

For states wary about legalizing marijuana use, one alternative is decriminalization — not criminally prosecuting those found in possession of marijuana, while still not permitting the outright sale of the drug through dispensaries or open retail (including the controversial sale of edibles, which arguably makes the drug more attractive to younger users). Before researching this subject, I was strongly in favor of legalization. After reviewing the evidence, I hold more reservations, particularly regarding the potential for spikes in use among teenagers and individuals with mental health vulnerabilities, as well as concerns about impaired driving. I remain in favor of decriminalization, but some states may have moved to full recreational legalization too quickly, without adequate time to consider more limited alternatives.

Works Cited

Cerda, M., et al. "Association of State Recreational Marijuana Laws with Adolescent Marijuana Use." JAMA Pediatrics, 171.2 (2017): 142–149.

"Colorado Division of Criminal Justice Publishes Report on Impacts of Marijuana Legalization in Colorado." October 28, 2018.

Hall, Wayne, and Louisa Degenhardt. "Cannabis Use and the Risk of Developing a Psychotic Disorder." World Psychiatry, 7.2 (2008): 68–71.

McCaffrey, Daniel F., et al. "Marijuana Use and High School Dropout: The Influence of Unobservables." Health Economics, 19.11 (2010): 1281–99.

Mohn, Tanya. "Driving Under the Influence: Legalized Marijuana's Impact on Traffic Safety Tackled In New Guide." Forbes. October 23, 2018.

"The War on Marijuana in Black and White." ACLU.