An examination of over 100 Covid-19 studies reveals that many relied on false assumptions that over-estimated the benefits and under-estimated the costs of lockdown. The most recent research has shown that lockdowns have had, at best, a marginal effect on the number of Covid-19 deaths. Generally speaking, the ineffectiveness stemmed from individual changes in behavior: either non-compliance or behavior that mimicked lockdowns. The limited effectiveness of lockdowns explains why, after more than one year, the unconditional cumulative Covid-19 deaths per million is not negatively correlated with the stringency of lockdown across countries. Using a method proposed by Professor Bryan Caplan along with estimates of lockdown benefits based on the econometric evidence, I calculate a number of cost/benefit ratios of lockdowns in terms of life-years saved. Using a mid-point estimate for costs and benefits, the reasonable estimate for Canada is a cost/benefit ratio of 141. It is possible that lockdown will go down as one of the greatest peacetime policy failures in modern history.
After more than a year of gathering aggregate data, a puzzle has emerged. Lockdowns were brought on with claims that they were effective and the only means of dealing with the pandemic. However, across many different jurisdictions this relationship does not hold when looking at the raw data.
A casual examination of lockdown intensity and the number of cumulative deaths attributed to Covid-19 across jurisdictions shows no obvious relationship.53 Indeed, often the least intensive locations had equal or better performance. For example, using the OurWorldInData stringency index (SI) as a measure of lockdown, Pakistan (SI: 50), Finland (SI: 52), and Bulgaria (SI: 50) had similar degrees of lockdown, but the cumulative deaths per million were 61, 141, and 1023. Peru (SI: 83) and the U.K. (SI: 78) had some of the most stringent lockdowns, but also experienced some of the largest cumulative deaths per million: 1475 and 1868.54
Using information from OurWorldInData, the cumulative deaths per million on March 28, 2021 in North America were 1351 and for the European Union 1368. Sweden had light restrictions, but cumulative deaths were 1327; while the UK had heavy lockdowns and 1868 cumulative deaths per million. This stands in sharp contrast to the dire predictions that were made about Sweden in the first six months of the pandemic.55
Similar findings arise when comparing various US states. Florida and California were often compared because they are similar in terms of size and latitude, but had different lockdown policies. Florida locked down in the spring but then started lifting restrictions, on September 25th, 2020 all restrictions were lifted. California has had various mandates throughout 2020, but in early December issued a stay-at-home order that remained in place until January 25th, 2021.56 However, the cumulative deaths per 100,000 people are practically indistinguishable: 152 for Florida and 143 for California.57
It is easy to find counter examples when using unconditional counts on deaths across different jurisdictions. That is, one can find cases where lockdown states had fewer deaths per million than some non-lockdown states (e.g. Ireland and Germany had high stringency indexes and below average deaths per million). However, it remains the case that lockdown is not associated with fewer deaths per million, but (likely) more.58
These unconditional observation puzzles are resolved by the research done over the past year. The preconceived success of lockdowns was driven by theoretical models that were based on assumptions that were unrealistic and often false. The lack of any clear and large lockdown effect is because there isn’t one to be found.
The consideration of any policy must consider all costs and all benefits of that policy. All estimates of costs and benefits depend on various assumptions of parameters and structural model forms, and many of the studies examined (especially the early ones) relied on assumptions that were false, and which tended to over-estimate the benefits and under-estimate the costs of lockdown. As a result, most of the early cost/benefit studies arrived at conclusions that were refuted later by data, and which rendered their cost/benefit findings incorrect.
Advances in models and data over the past year have showed that lockdowns have had, at best, a marginal effect on the number of Covid-19 deaths. Generally speaking, the ineffectiveness of lockdown stems from voluntary changes in behavior. Lockdown jurisdictions were not able to prevent non-compliance, and non-lockdown jurisdictions benefited from voluntary changes in behavior that mimicked lockdowns.
Using a cost/benefit method proposed by Professor Bryan Caplan the most reasonable cost/benefit ratio of lockdowns in terms of life-years saved in Canada is 141. However, given their limited effectiveness, lockdowns still fail under extremely conservative estimates of costs. Furthermore, if the fall of 2021 results in many cases resulting from the more transmissible delta variant among a shrinking number of unvaccinated people, then the expected benefits of lockdown policies become even smaller. Lockdowns are not just an inefficient policy, they must rank as one of the greatest peacetime policy disasters of all time.