The Volokh Conspiracy

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Free speech in the fog of scientific uncertainty


An e-cigarette (iStockphoto)

Donald Trump's assault on journalistic integrity and shared verifiable facts has ignited a reaction among public intellectuals to demand fealty to scientific truth. Unfortunately, the reaction, like so many produced in the haste of political controversy, has oversimplified and overcorrected for the problem. One common assumption within the resistance is that existing systems for regulating scientific claims are self-evidently wise.

My new article, "Snake Oil" (forthcoming in the Washington Law Review), is therefore coming out at a rather inconvenient time. I loathe the Trump administration's disregard for and delegitimization of scientific institutions, including expert federal agencies. Nevertheless, the methods that some expert agencies use to constrain the information flow to consumers are highly flawed.

Where evidence is strong and abundant, fealty to an expert opinion by nonexperts and lawmakers is sensible and efficient. But deference to an expert authority is not as wise where the science is weak and still developing. Too often, scholars and policymakers justify broad government powers to regulate speech about weak and contested science by bootstrapping their arguments to examples where the scientific evidence is strong (as with global warming) and where deference to experts is therefore highly sensible. But most of the hard choices that humans have to make, whether they are gravely important or relatively minor, are hard precisely because they concern factual questions with only a weak evidence base. Most decisions must be made where the science is still a fog.

Consider, for example, the Food and Drug Administration's and Federal Trade Commission's regulatory powers over health claims. Both agencies have broad powers to censor advertising that is made without sufficient scientific support. And they use high standards (usually two clinical trials, though one court has suggested that one should be sufficient for foods), effectively silencing commercial speech where an evidence base is weak or still developing. Scholars largely support the existing rules requiring agency pre-clearance and typically defend their constitutionality on the basis that unsubstantiated claims fall outside the coverage of protected commercial speech.

I disagree with the scholarly consensus. The strict standards applied to advertising are not consistent with free speech law, and they do a poor job of fostering debate and science literacy. They often have the effect of screening out the best available evidence because it falls short of the agencies' demanding requirements. At the same time, the standards tend to spur overconfidence in the claims that do meet the applicable standards, or that skate around the rules by making non-specific, comforting claims about health or wellness.

The greatest flaw in the FDA and FTC approach to advertising regulations is that the rules are designed to detect falsity rather than risk. Risk is, of course, related to the chance that a scientific claim turns out to be false, but falsity is not a good proxy on its own. The consequences from being influenced by a claim if it turns out to be false and the consequences of screening out a claim if it turns out to be true are often asymmetric.

The FDA's restrictions on advertising for e-cigarettes illustrate the problems with the current approach to commercial speech regulations. E-cigarette manufacturers cannot make promotional claims that vaping is healthier than cigarettes even though the best available evidence suggests it is. Moreover, the risks from screening out this information, if true, are much greater than the risks of allowing the claims to be broadcast even if they turn out to be false because the worst-case scenario for e-cigarettes is something comparable to the health consequences of smoking. Yet the advertising ban has slowed the progress that had been made in persuading smokers to switch to vaping. The concern that vaping will induce more teenagers to start smoking cigarettes also appears to be unfounded; states that allow the sale of e-cigarettes to minors actually have lower rates of teenage cigarette smoking than states that ban the sales, even with controls for preexisting propensity to smoke.

A similar lesson can be learned from the FTC's clumsy history with the egg industry, which I use as the key example in the introduction to "Snake Oil." The FTC prohibited the egg industry from stating that there is no evidence that the consumption of eggs increases blood cholesterol or heart-attack risks – a statement that was correct at the time and has stronger support today. Of course, the egg industry's ad campaign was completely self-serving, but the campaign would have served the public health as well because the fear of egg cholesterol drove consumers to eat even less healthy proteins such as pork and red meat.

There are other examples in which FTC or FDA rules served public-health interests, but these victories can be preserved by shaping a commercial speech rule around risk or harm rather than around "truth."

To a large extent, the problem I am describing is embedded in First Amendment doctrine. Central Hudson, the foundational commercial speech case, denied First Amendment protection to promotional speech that is false or misleading, so federal agencies and other lawmakers were encouraged to focus on the accuracy of advertising claims rather than the risks. But courts should begin the hard work now of readjusting free speech doctrine so that First Amendment protections are overcome only by concrete risks and harm rather than by inevitable doubts about the "truth" of a factual statement that is very difficult to test.

The adjustment will put some constraints on agencies such as the FDA and the FTC (as well as courts interpreting state and federal false advertising law) to ensure that enforcement targets specific claims that are not only likely to be wrong but to cause dangerous influences in consumer behavior. But this adjustment does not necessarily require the dismantling of current regulations. Many of the practices at the FDA and the FTC could be justified using a risk-centered approach. For example, First Amendment law should allow the FDA to defend a position, based on historical evidence, that drugs with no history of human consumption are presumptively harmful or ineffective until proven otherwise.

When it comes to already approved drugs, or to foods that have long been consumed by humans without acute negative effects, a categorical pre-clearance rule will be harder to defend on the basis of risk, but not impossible. Advertising rules that take both the weakness of an evidence base and the net effects of a false claim into account should be able to withstand First Amendment scrutiny. Free speech challenges can slowly steer false advertising law in this direction and make commercial speech doctrine more compatible with the general trend in First Amendment law to permit regulation only when the government has credible evidence of concrete harm.

Commercial speech is not the only area of First Amendment jurisprudence that suffers from too much focus on truth and not enough on risk; when it comes to speech of public concern, First Amendment law has similar flaws but with the opposite valence. It overprotects statements that contradict accepted and well-supported scientific knowledge that are made in public debate, even if the speech is very likely to cause foreseeable reliance and harm. In my next post, I will discuss how a harm-based approach can give the government a freer hand to regulate public discourse in instances in which junk science is likely to be false, influential and harmful.