Tyler Cowen's Teetotaling Blind-Spot

Tyler Cowen is a great economist and an incredibly thoughtful writer. But sometimes he gets things totally wrong. One of his major blind-spots is drug prohibition (even alcohol prohibition). It's not that he's in favor of it, as far as I can tell. But he downplays the likely benefits and exaggerates the hazards of relaxing prohibition.

Here he is in a recent post on marijuana legalization. He's linking to a Washington Post piece that supposedly argues against the iron law of prohibition: Drug concentrations rise under prohibition. People substitute from opium and morphine to heroin and (more recently) fentanyl. People consume whisky and gin instead of beer and wine. The post uses the example of recent marijuana prohibition to "disprove" this iron law. But I think it really misses the mark. At best it shows that sometimes drug concentrations can rise rather than fall after legalization. But clearly there is some truth to the notion that smugglers prefer a product that is less bulky. A bootlegger can carry ten times as much hard liquor as beer. A heroin dealer can shrink a one-ton shipment down to the size of a suitcase (or even a vial, depending on what class of synthetic opioid we're talking about!).

Marijuana seems completely different from these other substances. Some clever smuggler could conceivably distill pure THC to make it less bulky, but I'm not sure there would be much of a market for it. (Would typical marijuana smokers want, say, pure THC spritzed onto dried oregano? I'm thinking the market for this is thin.) Or maybe a clever cultivator could figure out how to grow a more potent strain. Then again, in an illegal market these strains would constantly be getting intercepted and disrupted by law enforcement. It would be hard to accumulate or share knowledge of this sort in an illegal market. Black-market "capital" keeps getting intercepted and destroyed. Low-grade illegal weed, bulky as it is, is probably "strong enough" for the typical user in a way that these other substances just aren't. In a legal market, cultivators can preserve potent strains and preserve the knowledge of how to grow them. This seems like a bigger deal for marijuana (where the dried plant is smoked directly) than for cocaine and heroin (where the dried plant is heavily processed and concentrated before being delivered to the user).

A couple things from that post struck me. Citing a study of marijuana in the Netherlands:

The researchers estimated that for every 3 percent increase in THC, roughly one more person per 100,000 in the population would seek marijuana use disorder treatment for the first time.

One additional person per 100,000 seems like a pathetically small effect. The study in question sees concentrations ranging from 8.6% to 20.3%. Increasing across this entire range would mean an additional 4 people per 100k seeking "use disorder treatment" (rounding up here a little). We're not even talking about something serious like "mortality" here. "Marijuana use disorder?" It's not addictive in the ways that other drugs are. You don't develop the dependence, withdrawals, or physical cravings. It's addictive in the way that video games are addictive. If four more people per 100k seeks treatment, that's a pretty low price to pay. Something like 7% of Americans have an alcohol use disorder. If there is any appreciable substitution from alcohol to marijuana, this price is well worth it. Eighty-eight thousand Americans succumb to alcohol-related deaths each year. That's 27 per 100k, not "seeking treatment for alcohol use disorder". That's dead. Cowen is a good economist. He should have reached for the concept of "substitute goods."

Here's the part that is Cowen's commentary:

I believe that marijuana legalization has moved rather rapidly into being an overrated idea.  To be clear, it is still an idea I favor.  It seems to me wrong and immoral to put people in jail for ingesting substances into their body, or for aiding others in doing so, at least provided fraud is absent in the transaction.  That said, IQ is so often what is truly scarce in society.  And voluntary consumption decisions that lower IQ are not something we should be regarding with equanimity.  Ideally I would like to see government discourage marijuana consumption by using the non-coercive tools at its disposal, for instance by making it harder for marijuana to have a prominent presence in the public sphere, or by discouraging more potent forms of the drug.  How about higher taxes and less public availability for more potent forms of pot, just as in many states beer and stronger forms of alcohol are not always treated equally under the law?

Props to him for making the moral case for legalization. But...an overrated idea? We're still sending people to prison for petty marijuana offenses. The stuff about IQ is just so much 1930s Reefer Madness hysteria. He offers no support for his suggestion that marijuana use lowers IQ. People in the comments push back on this extremely speculative claim, but he doesn't backtrack or answer them. (The comments section of Marginal Revolution is atrocious, but there are some gems if you can sift through all the garbage.) One commenter (#25 by Doug) points out that almost nothing permanently lowers IQ, so it would be a big surprise if marijuana did so. (Do read his comment, the replies, and Doug's reply to those replies.) This IQ comment is so bad, Cowen should to a massive mae culpa for misleading his readers with irresponsible speculation, and at a particularly bad time where policy is poised to shift. This kind of misinformation could stifle a golden opportunity for a good policy change, and that opportunity might not present itself for another decade or perhaps a generation.

This isn't an isolated incident either. He linked to this paper about repealing alcohol prohibition leading to more infant deaths. I'm thinking, Wait a minute! There are serious questions about whether prohibition reduced alcohol consumption at all. Weren't people poisoned by tainted bathtub gin? Didn't people drink alcohol that was intentionally poisoned by the U.S. government? Any claim that there were public health benefits due to prohibition are pretty hard to swallow, given that prohibition increased the toxicity of alcohol without much decreasing its consumption. And here's this paper suggesting that repealing alcohol prohibition caused ~13k excess infant deaths. It's hard to even take this seriously. (See Jeffrey Miron's Drug War Crimes on this; he fleshes out the argument that alcohol consumption didn't decrease appreciably during prohibition.)

Here Cowen lays out his case for a "voluntary prohibition" of alcohol, enforced by social norms and not by government policy. That's fair enough and nuanced enough, and I can respect that. Here's what he says:

I also think we should have a cultural shift toward the view that alcohol — and yes I mean all alcohol — is at least as dangerous and undesirable.  I favor a kind of voluntary prohibition on alcohol.

The "and yes I mean all alcohol" part struck me. I reject the notion that drug use per se, or alcohol use per se, causes social problems. My sipping on a beer or having a single shot of whiskey or glass of wine does not cause any appreciable damage, nor does it inexorably lead to greater alcohol consumption, nor for that matter does moderate consumption lead to problems. Sure, in a "but for" sense, you can blame alcohol: If the alcoholic or drunk driver couldn't get any, then their related social problems would disappear. But you simply can't make inferences such as "Drinking one beer causes you to ultimately drink ten beers." At best, Cowen's private prohibition should be applied specifically to problem individuals. I think he presents us with a false choice, where complete abstinence is easy but partial abstinence is difficult.

Oh, yes, and here's Cowen credulously repeating an easily-checkable claim by Scott Alexander, which grossly overstated Oxycontin-related deaths. I corrected him in the comments, and he conceded the claim "may not be correct." On the one hand, this is the internet working the way it's supposed to: Cowen and Alexander (and Robert VerBruggen, the original source of the bad info) all did mae culpas. On the other hand, it worries me that such an easily-checked claim (seriously, an easy Google search would have done it) can be repeated by such careful thinkers. It makes me reflexively doubt other claims repeated on Cowen's blog. As in, "Did he vet this at all, or is he just passing it along without really checking? Probably the latter."

I'll keep reading anything and everything that Cowen writes. Seriously, hail Tyler Cowen! He is one of my major influences. I've read most of his books and read most of his blog posts. He's usually spot-on and extremely incisive. But I think this is a huge blind spot for him.

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Addendum: I meant to make a bigger stink about this point. A basic economic analysis comes out strongly against drug prohibition. It does so even if you make heroic assumptions to revive it. See the Gary Becker et. al. paper. You really have to make stilted, almost contradictory assumptions in favor of prohibition. Like that people respond enormously to one risk (legal sanctions) while responding little to a risk of similar magnitude (pharmacological harms). I feel like this basic point is missing from Cowen's posts on drug and alcohol policy.