Alcohol prohibition led to problem drinking patterns like taking hard liquor shots of bathtub gin in secret speakeasies. Similarly, could cannabis prohibition be a cause of problem pot use?

Countries with decriminalization like The Netherlands and Portugal report lower rates of problem marijuana use than America. Now cannabis legalization in the United States promises to build on the theory.

The Washington Post reports today that marijuana use and dependency are down in America, amid the rise of taxed and regulated adult use pot programs, and medical marijuana regimes.

Federal data show the number of potheads dropped slightly from 2002 to 2014, amid the rise of medical and recreational weed in the U.S. Dependent marijuana users declined from 1.8 percent in 2002 to 1.6 percent by 2014, counter to the promises of legalization critics.

The Thursday report from the Substance Abuse and Mental Health Services Administration and the Centers for Disease Control and Prevention found declines in abuse and dependency were strongest among teens — a whopping 37 percent decrease. Young adults’ problem pot use dropped 18 percent.

Federal health officials surveyed 900,000 to get the data. The definitions of “dependence” and “abuse” came from the American Psychiatric Association.

About nine percent of people who try pot will at one point in their life meet criteria for dependence, experts say. Pot is not physically addictive, but can be as psychologically addictive as video games, or pornography. However, the criteria for pot dependence is subject to debate, since it includes prohibition-related consequences like “trouble with the law.”

Problem pot use is down, even as moderate use and heavy use is up, the CDC reported. Heavy use is up from 2 percent in 2002 to 3.5 percent in 2014, though heavy use fell among teens from 2.4 percent to 1.6 percent.

“Normally, researchers expect increases in heavy marijuana use to lead to more marijuana abuse or dependency. But the opposite seems to be happening here — abuse and dependency are falling as heavy use becomes more common. That represents a bit of a public health puzzle,” Washington Post’s Christopher Ingraham writes.

The CDC guesses that medical marijuana users might be using less potent strains. But it’s also common sense. When the law changes, one criteria for dependence goes away. “It stands to reason that fewer marijuana users have trouble with the law when the law allows marijuana use,” he writes.

Cannabis use in moderation appears to be increasing alongside perceptions of its safety. The share of Americans who see cannabis as having “no risk” doubled to 19.9 percent from 2002 to 2014.

This marijuana data comports with what historians and public heath experts know about other types of drug prohibition and patterns of use.

“It has frequently been observed that drug prohibition tends to drive out the weaker and milder forms of drugs, and to increase the availability and use of stronger and more dangerous drugs (see, e.g., Brecher, 1972). This has been so often reported that many analysts speak of it as an “iron law” of drug prohibition,” writes Harry G. Levine and Craig Reinarman in 2004. “This “law” of drug prohibition captures what happened during alcohol prohibition. The major effect of the Eighteenth Amendment was to dramatically reduce beer drinking (and therefore total alcohol consumption). At the same time, prohibition increased consumption of hard liquor (especially among the middle class). The fashionableness of the martini and other mixed drinks among the middle class is in part a historical legacy of prohibition, when criminalization made hard liquor the most available form of beverage alcohol.” “This change was not permanent — after repeal, spirits consumption fell while beer consumption rose.”

Alcohol prohibition also caused use distortions in several key groups relevant to the cannabis debate. According to a 1991 Cato Policy Analysis:

“It could be argued that Prohibition increased the demand for alcohol among three groups. It heightened the attractiveness of alcohol to the young by making it a glamour product associated with excitement and intrigue. The high prices and profits during Prohibition enticed sellers to try to market their products to nondrinkers–undoubtedly, with some success. Finally, many old-stock Americans and recent immigrants were unwilling to be told that they could not drink. According to Lee, ‘Men were drinking defiantly, with a sense of high purpose, a kind of dedicated drinking that you don’t see much of today.’

Do you think cannabis prohibition has distorted use patterns in America?

