When everyone is potentially lethal to others, without any individual choice on anyone's part.

In Reason, Eugene Volokh writes in part,

Right now, our bodies (at least until the availability of highly reliable tests for not being infected, or, better yet, being immune) are, for most of us, a potential source of infection and thus injury and death to third parties. The normal conditions that have justified liberty of movement and assembly in the U.S. for all my life unfortunately do not apply right now.

Now of course this raises all sorts of complicated questions. Obviously liberty emerged at a time when contagious diseases were both much more common and more deadly than they are today, because of the absence of effective prevention and treatment—consider, for instance, tuberculosis. Some amount of unintended risk created for others was seen as acceptable.

My sense is that our society is now insisting on a much lower threshold of acceptable risk, perhaps because we have gotten so used to a very low death toll from casually communicated illnesses (mostly from the flu and similar diseases). One can certainly debate whether we have adopted too low a threshold: Perhaps massive restraints on travel and assembly might be acceptable for diseases with the lethality of Ebola or some unvaccinatable-against mutation of smallpox, but shouldn't be acceptable for this strain of coronavirus.

And of course this is further complicated by the uncertainty of just how reliable various protective measures might be: For instance, if it we were confident that wearing a certain kind of mask would prevent the wearer from infecting others, then there would be much less justification for banning mask-wearers from traveling and gathering with others. Unfortunately, so much remains unknown about the facts here.

But the broader point is that the normal conditions that justify liberty of movement and travel—that make this liberty consistent with the libertarian judgments that each of us should have the right to do things that don't physically harm others—are regrettably not present when each of us (with no conscious choice on our parts) is potentially highly lethal to people around us. However peaceable we might be in our intentions, our assembling is a physical threat. Our judgments about liberty, I think, need to reflect that.

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