A full-throated defense of self-aware, voluntary drug use.

Hart, the first tenured African American professor of sciences at Columbia University and former psychology department head, calls himself “an unapologetic drug user.” His formulary is extensive, and it is likely only because he’s tenured that he so readily admits to a liking for—but not addiction to—heroin, along with an overstuffed medicine cabinet full of other substances.

His book has two overarching purposes. The first is to argue that the grown-ups of his title can indeed use drugs of varying descriptions—mostly marijuana, likely, but up to and including methamphetamines and opioids—and still be responsible parents and citizens. As the author suggests, millions of grown-ups already do so, and despite all the warnings and admonitions against it, by Hart’s lights even pregnant women can use a little here and there without being or producing monsters. “It doesn’t matter whether the drug is alcohol, caffeine, tobacco, or weed,” he writes of the last point. “Consumption of any of these substances should be taken in consultation with a health-care professional and should be limited.” His second large point is that the classification of drug use and public-health and law enforcement attitudes toward it is thoroughly racialized: Crack cocaine use was considered an epidemic evil when minorities, especially Black people, were using it. However, when it developed that “most crack users were white, and most drug users bought their drugs from dealers within their own racial group,” the epidemic became one of concern rather than fear. Hart’s openness in admitting to the use, often by way of experimentation, of drugs ranging from MDMA to methamphetamine and hexedrone and beyond is admirable, but doubtless, his thesis that taking drugs should be a matter of private choice alone will meet with considerable resistance.

Civil libertarians will find this a valuable tool for mounting arguments in defense of free choice.