How Legal Weed Avoided the Disasters Forecast by Prohibitionists

As millions across the country celebrate 4/20, it’s worth reflecting on how perceptions of marijuana have evolved. While I’ve never been particularly interested in cannabis—aside from one college summer—I’ve grown to appreciate 4/20 as a celebration of personal freedom. This shift mirrors broader public opinion: in 2025, 64 percent of Americans supported legalizing marijuana for both medical and recreational use, up from 31 percent in 2000, according to Gallup. Today, 40 states permit medical cannabis, with 24 of those also allowing recreational use.

Late last year, President Donald Trump signed an order to reclassify marijuana from Schedule I to Schedule III under the Controlled Substances Act, placing it alongside prescription drugs like ketamine, anabolic steroids, and Tylenol with codeine, as Reason’s Jacob Sullum explained. Yet prohibitionists had long warned that legalization would trigger catastrophic consequences. Here’s a look at three of their most alarming predictions—and why they never materialized.

1. Legalization Would Spark a Surge in Violent Crime

Before Colorado’s 2012 vote on Amendment 64—which made it the first state to legalize recreational marijuana—Douglas County Sheriff David Weaver cautioned voters that legalization would bring “many harmful consequences,” including “more crime.” However, research suggests otherwise. A Reason Foundation policy brief noted that studies on marijuana’s link to violence are inconclusive. While some research ties marijuana use to increased aggression, correlation does not equal causation. Several studies even contradict this association.

After legalization in Colorado, Washington, and Oregon, homicide rates in these states remained below the national average, despite a rise during the COVID-19 pandemic that mirrored national trends. From 1999 to 2022, the Reason Foundation report found that both recreational and medical marijuana legalization were “associated with a decrease in the homicide rate.” Similarly, a 2013 RAND Drug Policy Research Center report concluded there was “little support for a contemporaneous, causal relationship between [marijuana] use and either violent or property crime.”

Yet prohibitionists continue to push back. In March, Ohio Speaker of the House Matt Huffman (R–Lima) defended proposed THC limits by claiming that legalization in Ohio had led to “more marijuana being available in the community,” which he argued caused “more crime.”

2. Legalization Would Lead to Increased Teen Drug Use

Sheriff Weaver also predicted that legalization would result in “more kids using marijuana.” That fear, too, proved unfounded. In 2022, Nora Volkow, director of the National Institute on Drug Abuse, stated that “in the United States, legalization by some states of marijuana has not been associated with an increase in adolescents’ marijuana use.” Nationwide, teen drug use has been declining for years. In 2024, the National Institutes of Health reported that “substance use among adolescents has continued to hold steady at lowered