One of the key themes of Economics In One Virus is that it can be very difficult to disentangle the effects of voluntary behavioral change from public policy. Another way of putting this is that “defining the counterfactual” is hard. In a world in which public policies can crowd out private action, or else merely codify it, you should not judge the wisdom of an action by the outcomes associated with that action being mandated.
An interesting example of this in the pandemic relates to mask mandates and mask wearing. Studies on the effectiveness of government mask mandates have so far produced mixed results—ranging from almost no effect alongside other interventions to pretty significant impacts in Germany. Quite often people on both sides of the mask debate have jumped to conflate their favorite mask mandate study results with the impacts of mask wearing writ large. “See, mask wearing doesn’t work!” they say when mandates are found not to reduce case trends. Or “see, mask wearing does work!” when they do.
Libertarians should understand, though, that just because a government mandates something does not mean that that mandate automatically changes behavior. People might voluntarily wear masks even before a mandate, meaning the mandate has little marginal effect. People might choose not to comply with mandates, just as many don’t comply with drug laws. A mask mandate might be taken as evidence by the population of a rising risk of the virus and so lead them to other social distancing measures that mitigate the spread of the virus without wearing masks more often. Quite simply, the introduction of government mask mandates may fail to correlate well with the extent of actual mask wearing behavior and so the expected effect on the transmission of the virus.
A new epidemiological study highlights this. Looking across a range of countries, it finds that government mask mandates do not correlate well with increases in self‐reported mask wearing in most places:
South Korea’s mandate came after voluntary wearing had already plateaued at 94%; conversely, in the Netherlands and Switzerland, few people were wearing masks, even three weeks into the mandate period; finally, in the Czech Republic, wearing eventually increased, but only long after the mandate was implemented.
While in some countries and U.S. states the trend in mask wearing seemed to change sharply after a mandate, in most cases “the increase in mask‐wearing occurred before the earliest national government mandates.” Looking at how mandates affected case growth as a proxy for mask wearing generally then might have badly understated how effective (voluntary) mask wearing efforts and private business requirements were in mitigating the transmission of the disease.
This new study uses a huge self‐reported survey data set on mask‐wearing behavior and links it to cases of the virus in 92 regions across six continents, controlling for the mobility of the populations and other lockdown measures. It finds a significant average effect of more self‐reported mask wearing, such that “an entire population wearing masks in public leads to a median reduction in the reproduction number R of 25.8%.” This may prove an underestimate of the effect of rigorous mask wearing, given these surveys can include people wearing cloth masks and perhaps only wearing them on public transport slightly more than half the time.
Crucially though, the study’s overall results do not find any evidence that government mask mandates reduce transmission of the virus. Yes, in some countries mandates appeared to increase self‐reported mask wearing. Perhaps announcing a coming mandate causes an uptick in mask use in anticipation of the new laws too. But the results of this modelling across all countries finds no overall effect of a mandate actually coming into force.
Why does this matter? Well, as the retrospectives on COVID-19 are written, there will be a debate about whether government coercion was necessary or beneficial relative to mere guidance and/or the development of social norms for particular mitigation behaviors. A lot of debate takes place as if mask mandates are synonymous with mask wearing, but as I write in my book:
To assess the wisdom of a government mandate, we’d have to take the approach outlined in chapter 6 and compare the marginal benefits and costs of a law above and beyond what could be achieved with less‐coercive means, such as recommending that retailers, private residence blocks, and other organizations institute their own policies. Such a marginal analysis would mean assessing how many additional people would wear facemasks if it were mandated as opposed to being guidance and how this would affect transmission of the virus. These benefits would then be weighed against the costs (social and fiscal) of the compulsion, such as the policing of the law, including enforcement of the requirements and penalties for noncompliance.
This new study suggests that those marginal benefits of mask mandates above and beyond voluntary behavior may have been very much smaller than many people imply.
But, second, if these results are confirmed, then it suggests that public attitudes about the efficacy of mask wearing might have been much more important than subsequent mandates in delivering better public health outcomes. That makes the flip‐flopping on masks by public health officials early last year more significant. If you remember, Anthony Fauci and the Surgeon General Jerome Adams explicitly told people not to buy masks, implying they did not work in the community, based on a faulty hunch that the virus was only transmitted by symptomatic spreaders. This muddied the water on the public’s perception of whether masks helped reduce transmission at an early stage of the pandemic.
Commentary by Ryan Bourne. Originally published at Cato At Liberty. https://www.cato.org/blog/dont-confuse-mandates-changing-behavior