Jerry Lampen / Reuters

Mark Kleiman, a professor at New York University who was one of the nation’s most respected scholars of criminal (and especially drug) policy, died last week after a kidney transplant from his sister Kelly failed to take. As one of the many journalists whose work was improved by Kleiman’s ideas (this September 2010 Atlantic feature on alternatives to prison was inspired by his book When Brute Force Fails), I have been happy to read the tributes to him from diverse sources, and am eager to include my own.

Nothing I could write could add or detract from his own eloquent and informed opinions on prisons or cannabis legalization. As pet causes go, these were Kleiman’s bullmastiffs. But he had a few Chihuahua-sized ones, too, that he wrote about less frequently. He sympathized with Sally Satel’s arguments about compensating kidney donors, and called out bioethicists’ unwillingness to contemplate such measures for being irrational, a quasi-theological position similar to abortion foes’ failure to distinguish, morally, between zygotes and babies.

The argument I take up here in tribute is about hallucinogens—the class of drugs that includes acid, magic mushrooms, and ketamine. Kleiman thought certain hallucinogens should be legalized, ever so carefully, and for reasons distinct from his arguments for noncommercial decriminalization of cannabis. He was absolutely right.

Smoking lots of pot really can rob you of your ambition, and cannabis-use disorder—CUD, or pot addiction—is a real thing that can take away years of your productive life, if you belong to the roughly one-tenth of pot smokers who smoke too much and let cannabis get in the way of other things, like work, study, or family. Problem smokers keep smoking too much for 44 months, on average—“not a small chunk to take out a lifetime, especially a young lifetime,” Kleiman wrote. For that reason, Kleiman thought states should legalize pot in ways that would minimize excessive use. First, don’t let distributors advertise or otherwise encourage their customers’ habits. I once lived two blocks from a legal cannabis dispensary, and it took me a year to realize what it sold, so subtly did it market its product. Second, keep prices very high, far higher than the few pennies it would cost to grow and sell a joint. Make pot expensive enough that occasional users barely notice the cost but addicts do and feel spurred to cut back as their bank accounts decline.

Hallucinogens do not seem to have comparable addictive effects. Taking them is not like being a kid on a roller coaster who runs back into the line to ride again as soon as the train coasts to its terminus. The explorer Wade Davis compares the experience of a nose powder used ritually by the Yanomami to being “being shot out of a rifle barrel lined with baroque paintings and landing on a sea of electricity.” I have no idea what this means, but I am certain that the experience is so intense that no normal person would want to get out of the electricity sea, towel off, and stuff himself right back into the rifle barrel. Take enough cannabis, cocaine, or opium, and you’ll sharpen your craving for more. Hallucinogens, however, typically kill off any craving for more hallucinogens for a good amount of time. (Ketamine is an exception, both addictive and able to kill you, if you take too much and choke.)

But what of the possibility that hallucinogens will permanently scramble your brain? As a teenager I heard the tall tale about an acid freak who never came down from his bad trip, and is doomed forever to believe he is an orange. These and similar urban legends do not appear to have been confirmed in the medical literature. But the chances that your trip will be bad, and that you will emerge from your trip shaken and traumatized, are substantial. To make matters worse, hallucinogens tend to warp one’s sense of time, freezing it and making a 10-hour trip feel like a literal eternity, beyond time itself. “Have you ever traveled to the Mountain of Shame and stayed for a thousand years?” Sam Harris, a former psychonaut, once asked. “I do not recommend it.”

Not many people would, I suspect, be so attracted by being shot out of a Rijksmuseum-lined rifle that they would risk a chance of a millennia-long detour in hell. So the appeal of these substances is already limited, and the heedless trippers who use them anyway probably won’t make them into a habit. What of the benefits?

Here Kleiman, a committed empiricist whose group blog calls itself “the Reality-Based Community,” revealed a certain capacity for poetry. He noted that a large fraction of trippers had life-changing, and often life-affirming, experiences—ones that vanquished fear of death, inspired creativity and compassion for others, and improved moods and depressive tendencies for months after a single dose. If Prozac had the effects observed in the best current studies on psychedelics, withholding it from the depressed or dying would be considered a human-rights violation as serious as failing, out of spite, to set a broken leg.

And that is how Kleiman suggested we think about legalizing hallucinogens: as a change in policy that was less about the weighing of a policy’s pluses and minuses than about the dignity and rights of human beings and citizens. The First Amendment guarantees freedom of religion, Kleiman said, and by any objective standard the experiences of many who take hallucinogens are religious. Seeing God after eating shrooms is subjectively indistinguishable from seeing God by reading Rumi or meditating and eating nothing but bitter herbs in a cave for a few weeks. That LSD is associated with dirty hippies should not give the government license to deprive everyone of (to use William James’s phrase) a variety of religious experience.

The psychologist Robert Gable relates the experience of a man dying of cancer who, aided by a pharmaceutical cocktail, slipped into a hallucinatory state. Gable asked him the next day whether he found the state pleasurable, and the man teared up. “Oh, yes,” he replied. “But I am too sick to do this now. Why didn’t somebody tell me about this?” “I took his bony hand and held it in mine,” Gable says, “because I didn’t have an answer.” Neither did Kleiman (who, according to his New York Times obituary, “had not been averse to using psychedelic drugs”).

Religious experiences have inspired destructive behavior, and putting LSD in the water supply of Gotham would have roughly the effects predicted in the Batman movies. Kleiman was fond of quoting Timothy Leary: Hitting golf balls is a harmless activity, but you have to do it in certain designated areas, under the supervision of golf pros. You can’t just go to Central Park and yell “Fore!” Similarly, the few people eager to drop acid or take shrooms should do so in special facilities, staffed by psychedelic professionals trained to keep them from freaking out if things turn unpleasant. The facilities should have environments conducive to safe, rewarding trips, and would more resemble meditation retreats than hospitals.

The city of Denver recently moved to decriminalize possession of magic mushrooms (psilocybes), among the most benign of this benign class of drugs. Amsterdam, though better known for its weed, allows discreet sale of mushrooms. The wider availability of these substances ranked low on Kleiman’s list of priorities—as criminal-justice policies go, he thought taxing alcohol, emptying prisons, and lead abatement were all more urgent—but it would be a transcendent pleasure to see this other cause added to the agenda.

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