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How to prevent casual pot smokers from slipping into abuse and dependence

A modest proposal on 4/20: a user-set quota system could help people moderate their marijuana use.

colorado 4/20
A 4/20 celebration in Colorado.
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On April 20 — the informal holiday known as 4/20 — cannabis users celebrate their favorite herb. The day features both heavy smoking and long impassioned speeches in favor of allowing adult consumers unfettered legal access to a substance that some 37 million Americans report having used in the past year.

Those celebrations will not, however, be quite universal, even among cannabis consumers. Presumably most of the roughly 500,000 people whose cannabis use sends them to a hospital emergency department in a typical year — usually as a result of overconsumption, leading to a scary and unpleasant few hours but no lasting injury — will celebrate with reservations, if at all. Those who suffer from the much rarer but much scarier Cannabis Hyperemesis Syndrome, characterized by uncontrolled vomiting, are no doubt even less happy.

You’d expect equally little enthusiasm from the estimated 4.1 million who, by their own self-report, appear to meet the diagnostic criteria for cannabis use disorder. These people use marijuana more, or more often, than they want to; they’ve tried, unsuccessfully, to cut back or quit; they find that cannabis interferes with their other interests and responsibilities; and their use has led to conflict with people they care about.

There are uncounted others who appear to the people around them to have some of these issues, but who don’t acknowledge it. (Not everyone with a drug problem is self-aware.) Of course, those for whom cannabis is a burden rather than a pleasure also have families and friends, who suffer vicariously.

We’re heading toward the “alcohol model,” but there’s still time to shift course

Marijuana policy is heading inexorably toward the model we use for alcohol — weakly regulated commercialized legalization, with taxes that are too low. That’s been a public-health disaster in the case of alcohol. Cannabis isn’t as dangerous, but there’s still no good reason to repeat that mistake. Taxes should be higher and marketing restrictions tighter; there’s even a case for keeping commercial enterprises out of the industry altogether and restricting sales to consumer-owned co-ops.

But here’s a more outside-the-box idea, designed to help people exercise self-restraint about how much cannabis they use and how often: a system of user-set monthly purchase limits.

Under such a system every buyer would be required to set up an account (with a number rather than a name, to protect privacy) and to choose a monthly quota, stated in milligrams of THC. Every purchase, wherever made, would be registered against that account number, and when the user’s own chosen limit was reached, no further purchases could be made that month. (The system could be state-run, or federal.) As an escape hatch, a user could be allowed to increase the quota after a one-week waiting period.

The myth that marijuana is harmless

The biggest barrier to adopting this idea, or any idea for adequate cannabis regulation, is the widespread belief that cannabis is “natural,” “harmless,” and “non-addictive.” Those beliefs are partly an overreaction against “reefer madness” propaganda, partly the product of the zeal of legalization advocates, and partly a result of the skilled marketing and lobbying efforts of the cannabis industry.

Today’s cannabis is several times as potent as it was a generation ago. Stores in the states where cannabis is now openly sold under state law compete to offer stronger and stronger pot; reported percentage THC content on the stores’ online menus now averages in the mid-teens, with some strains claiming to be as high as 25 percent.

Legalization advocates confidently predicted that users would compensate for higher potency by cutting back their consumption, but that hasn’t happened. The number of people who report using cannabis daily or nearly daily has multiplied by approximately a factor of seven over the past quarter-century. It now stands at some eight million (out of 37 million who have used it in the past year).

Other studies find that those daily and near-daily users consume about three times as much cannabis per day of use as more casual users. More evidence that people aren’t adjusting for potency: The estimated dollar value of cannabis sales has soared, even as potency-adjusted prices have fallen drastically.

There’s no reason to think that occasional cannabis use is harmful, but there’s just as little no reason to think that frequent heavy use is benign, and a substantial body of evidence challenges the myth of harmlessness. One Dutch study, for example, found that excluding foreign students from buying cannabis in “coffee shops” led to improvements in their grades, while the grades of their Dutch classmates, who still had access, stayed flat.

Speaking out about the risks of cannabis should not be equated with supporting prohibition

None of this means that cannabis ought to remain illegal. Prohibition is simply no longer a practical option. With the estimated retail cannabis market now above $40 billion per year, with state after state permitting an activity the federal government still forbids, with increasing concern about too many arrests and too much incarceration, and with the need to focus drug enforcement on the supply of heroin and the fentanyls, there’s no way to put the genie back in the bottle, even if the public wanted to, which it overwhelmingly doesn’t.

The only remaining practical question — much as the die-hard drug warriors deny it — is what form legal availability will take. Following the alcohol model will lead to ever-higher levels of problematic cannabis use. According to Jonathan Caulkins of Carnegie Mellon and Steven Davenport of RAND, cannabis prices in Washington and Colorado are falling at 2 percent per month; one store in Seattle now sells what it claims to be 16 percent THC flower at $15 per quarter ounce. That translates to about 25 cents a stoned hour — much cheaper than an alcohol buzz.

Since legal cannabis is remarkably cheap to grow, and since competition will force prices down to no more than a reasonable margin over production costs, the bottom is not in sight. And taxes assessed as a fraction of retail price will fall as prices fall.

Low prices generate high volume, but they also mean that high volume is the only way the industry can stay in business. Daily and near-daily users account for some 85 percent of current cannabis sales. That means the for-profit commercial industry will, like its illicit counterpart, and like the alcohol industry, be financially dependent on the minority of users who are chemically dependent. That industry will do everything in its power to create and sustain the biggest possible population of chronic stoners.

That’s the bad outcome user-set quotas might help prevent. Virtually no one starts out wanting to be a three-joints-per day smoker, spending most of his or her waking hours under the influence. A quota system would prevent some people — there’s no way in advance to tell how many — from sliding down that slippery slope.

User-set monthly limits aren’t a perfect policy

Of course, no system could make it impossible for someone to lose control of his or her cannabis use. A user could choose to set a very high initial limit, or keep increasing the limit to accommodate a growing habit. But some would choose a modest limit, and would regard hitting their quota early as a signal that they were using more than they intended to.

But a user-set quota system would also do very little harm, since it wouldn’t actually limit the freedom of any user more than trivially. Users could even choose to opt out by choosing an absurdly high limit.

So here’s a thought to keep in mind as you light up: There’s no contradiction between deciding a commodity ought to be legal and still thinking that some people might need a public-policy “nudge” to keep their use of that legal commodity under control.

Mark Kleiman is professor of public policy at NYU’s Marron Institute. His book on drug policy is Against Excess. He is the co-author, with Jonathan Caulkins and Beau Kilmer. of Marijuana Legalization. He blogs at The Reality-Based Community and can be found on Twitter @markarkleiman.

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