Science and policy are often in tension with one another, but in the case of cannabis, as medicinal or recreational marijuana, science seems to be playing catch-up.
“Cannabis was scheduled [made illegal] in the absence of science,” and now is being legalized in some areas, still in the near-absence of science, said J. Michael Bostwick, a practicing psychiatrist and a senior associate dean at Mayo Medical School. In 1970, when Congress classified cannabis as Schedule 1 (“drugs with no currently accepted medical use and a high potential for abuse”), scientists did not know which neuronal receptors it activated or what exactly in the substance was causing which effects.
More than four decades later (and 5,000 years since people first started using it as pain reliever), we still don’t know much more of the botanical substance’s potential as a medicine, because its Schedule 1 status means US researchers have to jump through hoops at several different agencies to get access to the legal federal supply. That’s just the start, science-wise: As with any plant, cannabis varies widely in quality, strength, and in what other compounds are bound within the plant, so research—and comparing previous studies in the US and elsewhere—can be tricky.