David Pozen’s The Constitution of the War on Drugs is a fascinating and thorough history of constitutional challenges to drug laws, and well worth reading—though the way this history is framed can be maddening.

In the book’s strident introduction, Pozen declares the drug war to be a “policy fiasco” with virtually no support among serious experts. The book’s purpose, he says, is to explain why the resistance to this fiasco so rarely takes the form of constitutional challenges, rather than policy arguments and legislative efforts.

Yet his project, Pozen also writes, concentrates especially “on the physically nonaddictive ‘soft drugs,’ above all cannabis.” Some reasons for this focus are fair enough: Such drugs have spurred the most constitutional litigation, he says, and their prohibition is the most debatable as a policy matter. However, Pozen also argues that soft drugs dominate the drug war itself. He notes that marijuana generates the most arrests and that the drug war has been a war on pot in “significant part,” then uncritically quotes an ACLU executive director claiming, around the turn of the century, that “if you took marijuana out of the equation, there would be very little left of the drug war.”

This fundamentally misunderstands the War on Drugs, with implications both for whether the drug war is a failure and, more to the point, how much of the war could even conceivably be called unconstitutional.

Arrests are only one part of America’s anti-drug efforts, and the system makes enormous distinctions among different types of drugs and different types of behaviors. Imprisonment paints the other half of the picture. As of 2004, well before the current trend toward weed legalization, only about 13 percent of state and federal drug prisoners were serving time for marijuana-related offenses; the most common drug offenses involved cocaine. Furthermore, imprisoned drug offenders are overwhelmingly traffickers, not merely users.

Hard drugs are the cause of most drug imprisonment (mainly among dealers) and also the most carnage (mainly among abusers). There are good reasons to prohibit commerce in the most lethal drugs, given the six-figure annual death toll of US drug overdoses and the ample evidence that prohibition reduces drug use. These tradeoffs, which I would consider the core issues of the War on Drugs, are far more difficult than the question of legalizing and regulating weed—which, to be clear, I’m sympathetic to myself.

And at the level of constitutional challenges, an asserted right to, say, toke up in one’s own home is quite different from a right to, say, deal cocaine. Pozen is clearly sympathetic to the former—and it’s indeed an interesting question why the “right to privacy” lurking in the Constitution’s penumbras was taken to protect contraception and abortion, but not marijuana, during the heyday of left-wing judicial activism. But the trafficking of hard drugs is where the big guns of the War on Drugs come out, and there’s little hint in this book that any feasible approach to the Constitution could create a right to engage in such.

With that background firmly in mind, readers may end up reading The Constitution of the War on Drugs through a more cynical lens than Pozen intended. The important question is not “Why oh why didn’t courts valiantly end the brutal War on Drugs, which is almost entirely about little old marijuana?” It is, “How did the courts manage to leave drugs—even soft drugs—alone while meddling in so much else, via dubious constitutional arguments, over the course of the twentieth century?”

The good news is that the rest of the book—more descriptive than prescriptive in nature—answers that question, provides tons of interesting case history along the way, and notes a few areas where even skeptics might concede a plausible constitutional case against certain drug policies.

The Constitution of the War on Drugs is divided into a series of chapters focused on different constitutional arguments one might make for drug rights. The first two focus on the most obvious candidates, including natural rights, privacy, and federalism.

Through much of US history, the federal government was limited in its ability to regulate purely within-state activity, but the states had considerable “police power” to do so themselves. Starting especially in the mid-1800s, many states regulated or banned alcohol and other substances. These laws were challenged in court, and the challenges were more successful than one might expect. Many judges shared an assumption that even states could not regulate private behavior that didn’t harm others. In 1855, the Indiana Supreme Court struck down an alcohol ban on essentially these grounds; the Kentucky Court of Appeals dismissed a case involving alcohol in a dry town in 1909.

Yet such rulings were far from ubiquitous, especially when states could argue that drug use harmed others besides the user—and even if states could not touch private possession and consumption, they could still ban commerce. Several states’ courts upheld opium bans, Tennessee’s okayed a cigarette ban, and, Pozen writes, “a clear majority of courts upheld restrictions on the manufacture and sale of intoxicating liquors after the 1850s,” as these non-private behaviors fell more clearly within the police power.

However limited these restrictions on government regulation may have been, they did not survive the first two decades of the twentieth century. Most states enacted narcotic prohibitions during this period, half prohibited alcohol, some banned pot, and the federal government passed its first anti-drug laws, targeting opium and other narcotics. The Supreme Court upheld the federal narcotics regulations as an exercise of Congress’s taxing power—and also found that states could prohibit alcohol possession in addition to commerce, at least as far as the federal Constitution is concerned.

The Eighteenth Amendment banned alcohol production, transportation, and sales nationwide in 1919. And then the New Deal years only broadened the federal government’s ability to regulate, especially through the Supreme Court’s broad interpretation of the Commerce Clause.

But that brings us to the classic era of liberal judicial activism, with its expansive view of the right to privacy outlined in 1965’s Griswold and 1973’s Roe. There were, unsurprisingly, some efforts to apply this concept to drugs—but these efforts bore little fruit.

They did generate some minor rulings in state courts, including when the Alaska Supreme Court protected marijuana on privacy grounds in 1975, but limited the right to the home and made clear it wouldn’t apply to harder drugs. That ruling is still the law in Alaska (alongside a 2014 ballot measure legalizing pot), but Pozen reports that the possibility of a Roe for weed was over by the early 1980s. Courts distinguished drug use from procreation, found getting high not to be a “fundamental” right, and expressed reticence to override the elected branches of government in this area. Forcing every state in the country to allow abortion was one thing, but forcing them to allow pot smoking in the home was a bridge too far.

When the Court drifted back to the center, one might have expected at least the federalism-based arguments to make a resurgence. But no: In 2005’s Gonzalez v. Raich, with none other than Antonin Scalia concurring in the judgment, the Supreme Court upheld the federal government’s ability to prohibit even medical marijuana grown at home for personal use, as part of its efforts to regulate the interstate pot market.

There have been other opportunities to enshrine drug rights in the Constitution as well.

For example, some have argued that drug policies violate equal protection when they, for example, punish marijuana similarly to hard drugs while allowing alcohol to be sold freely. Some courts in the 1960s and 1970s held that classifying marijuana as a narcotic failed rational-basis review, though this naturally required them to make judgment calls as to how harmful which drugs were and how much leeway legislators should have to make those calls themselves. (One trial judge even decided cocaine was less dangerous than both alcohol and nicotine in 1976.) Ultimately, courts dropped this line of reasoning, highlighting scientific uncertainty about pot’s effects and deferring to legislators as to how to approach it.

Racial disparities provide another equal-protection angle for attacks against the drug war. In Washington v. Davis (1976), however, the Supreme Court held that challengers need to prove actual discriminatory intent unless a law explicitly discriminates by race, not merely that one group is more affected by a law than another. That decision made it difficult to invalidate drug laws or their enforcement. Even the 1986 law creating a 100:1 disparity between powder and crack cocaine generated little judicial pushback, with judges noting numerous distinctions between the drugs, such as crack’s unambiguous connection to a gang-violence epidemic at the time. Two exceptions came from the Minnesota Supreme Court, which struck down a similar state law by reading a sort of disparate-impact rule into the equal-protection clause of the Minnesota constitution, and a federal judge in Missouri, who contended that “unconscious racism” provided the needed discriminatory intent behind the federal law’s disparity.

The Eighth Amendment’s bar against cruel and unusual punishment offers yet another potential avenue for a constitutional limit to the War on Drugs. In Robinson v. California (1958), the Supreme Court struck down a law that criminalized being addicted to—as opposed to, for example, buying or using—narcotics. But, as happened with so many other lines of argument, follow-up cases had only scattered success, and certainly never remade American drug law. The single best anecdote in the book is Powell v. Texas (1968), in which four Supreme Court justices, just shy of a majority, argued it was unconstitutional to punish someone for public drunkenness, provided they were a chronic alcoholic who couldn’t help it.

There were also more straightforward arguments that a given drug sentence was simply too much. These worked occasionally in the 1970s, though they never won the support of the Supreme Court, which has always balked at overturning non-death-sentence punishments and upheld a life sentence for possession of about a pound-and-a-half of coke in 1991. Interestingly, courts have been more willing to invalidate disproportionate fines, as opposed to criminal sentences; after all, the Eighth Amendment bars fines if they’re “excessive” but criminal punishments only if they’re “cruel and unusual.”

Lastly, Pozen covers free speech and religious arguments. The idea that doing drugs is a form of speech or facilitates “chemically assisted free inquiry” predictably never gained much traction. Given the historic use of drugs in certain religious ceremonies, however, the freedom-of-religion argument is much less frivolous, if limited to specific contexts. Even here, though, the Supreme Court famously refused to require an exception to drug laws for Native Americans’ use of peyote, with Congress and some states later picking up the slack.

Pozen wraps up the book by discussing other approaches courts might take to drug laws. Elsewhere in the world, for example, many courts take it upon themselves to decide whether drug laws are proportional to the harms they address—openly contemplating the pure policy arguments that in the United States are generally left to legislatures. Of course, doing that here would require a total overhaul of the role of the judiciary, and would empower unelected judges to override elected politicians based on policy disagreements. Pozen further notes that “even the most libertarian proportionality rulings have allowed the state to continue to restrict drug production, distribution, and possession with intent to distribute.”

A little more realistically, even an originalist judge might become more open to challenges based on protections for religion or the ban on cruel or unusual punishments (as there are reasonable historical arguments that this includes extremely disproportionate punishment). Originalists might also want to restore some of the old limits on federal power and a stricter interpretation of the Commerce Clause, leaving these matters more to the states. Most likely, though—as Pozen does not deny—the Constitution will continue to factor little into questions of what America’s drug laws should look like. One might think that’s bad or good, but either way, The Constitution of the War on Drugs explains how it became the firmly entrenched status quo.