Marijuana Policy in a Fragmented Legal Structure

I’m someone who generally favors the notion of US state as the “laboratories of democracy,” as US Supreme Court Justice Louis Brandeis wrote back in 1932. The general idea is that, within the parameters set by the US Constitution and by federal law, states should be able to experiment with policies and programs. The hope, of course, is that policy can be more responsive to the preferences of people living within each state, and also that demonstrably successful experiments will spread and demonstrably failed experiments will contract. But US policy with respect to marijuana is a mess, and in a way that may pose health issues. Symone T. Griffith, Marisa L. Kreider, and Maxwell C. K. Leung explore the topic in “A Coordinated Approach to Cannabis Policy and Product Safety” (Issues in Science and Technology, Fall 2025). The authors explain:

After decades of advocates’ activism at the state level, medical cannabis is now available for purchase by patients with qualifying medical conditions in 40 states, four territories, and the District of Columbia. However, at the federal level, cannabis remains classified as a Schedule I substance. Along with LSD, ecstasy, methaqualone, peyote, heroin, and other substances, cannabis is federally deemed to have no accepted medical use and a high potential for abuse. Furthermore, a shifting menu of state-by-state regulations determines what conditions qualify patients for medical cannabis. Figure 1 illustrates the expansion of cannabis legalization and inclusion of PD, cancer, pain, and anxiety in qualifying condition (QC) lists from 2019 to 2025. As more people gain legal access to recreational and medical cannabis, the effects of the inconsistency between federal policy and patient care are compounding.

Of course, using states as “laboratories of democracy” will result in some differences across states. But look at the variation in how many states allow medical uses of marijuana for Parkinson’s, cancer, pain, and anxiety–and how many don’t. Look at how many states added certain medical uses of marijuana in the last six years. I strongly suspect that these variations across states and the changes in recent years have almost nothing to do with medical findings, and have just resulted from the workings of state-level politics.

Indeed, because of how marijuana is classified by the federal government, there is relatively little research on whether (and how, and in what dosages) marijuana would actually work as a medical treatment; instead, because of how the federal government classifies marijuana, most of the medical research is about risks of addiction. Indeed, many of those using marijuana for medical reasons seem to be purely self-medicating, in the sense that they are treating marijuana as an over-the-counter drug and haven’t talked over with their health care provider. Beyond the medical uses, every state with legal marijuana use has to support its own system of laboratory testing for safety and purity. The usual pattern is that the state gives licenses to third-party laboratories, who are then paid by cannabis producers to do the testing–an arrangement which holds potential for a conflict of interest.

I’ve never used marijuana, and have no plans to do so. As someone who drinks alcohol, I have no strong basis for arguing that some other intoxicant should be illegal. But having something that is both legal and illegal is poor civic hygiene. Rules about driving under the influence or public intoxication need to be applied equally across substances, as do rules about public smoking. Moreover, having the question of whether a certain medical treatment is safe and effective decided by the vote of state legislators–especially when the patient is choosing a personally preferred dosage–seems like a bad look for public health policy, too.

The post Marijuana Policy in a Fragmented Legal Structure first appeared on Conversable Economist.