The basic argument for quarantining is that in emergency scenarios, individual rights must be sacrificed for the collective interest. In the U.S., the constitutional basis for quarantining is somewhere between tenuous and nonexistent, depending on which legal expert you ask. A massive imposition like China’s would be unconstitutional, according to James Hodge, a health-law professor at Arizona State, who noted the likelihood of human-rights violation in such a scenario. Another skeptic, the Georgetown University legal scholar Alexandra Phelan, likened China’s response to a “sledgehammer.”

In theory, a sledgehammer sounds good and decisive. But responding to an emerging epidemic requires precision closer to brain surgery. Shutting everything down may help contain the virus—but also may help spread it by keeping people concentrated in crowded cities. This can create other health issues related to scarcity of resources and intensify panic. Quarantines can actually prevent treatment and detection if they are seen as punishments for reporting symptoms. If people do not trust that doctors and health officials have their best interest at heart—or if people believe them to be acting on a political imperative from above—they are much more likely to play down or ride out symptoms. If this happens, it takes longer for everyone to have a sense of the scale and scope of the outbreak, and to understand how it spreads.

This effect is especially possible in authoritarian states, but crises invite unusual exercises of state power anywhere.