Some logical surmises exist for why the pandemic would have driven down property crime. More people were at home in 2020, and burglars generally avoid occupied houses, hence the drop in burglaries. That might also explain why robberies, a violent crime, sank—if fewer people are on the street and many businesses are closed, a would-be robber has fewer opportunities—but vehicle thefts, a property crime, rose, because cars were left on streets rather than being driven to work. Yet if the pandemic helped depress property crime, the result follows a years-long trend. Since a recent peak in 1991, overall property-crime rates rose only once.

How the pandemic and last summer’s protests connect to the rise in violence is more complicated. The stress and strain of the pandemic on citizens—lost jobs, sick relatives, being forced into close quarters—could increase a propensity for violence. Many government and nongovernment programs that create diversions from conflict were closed, including formal education, after-school curricula, and violence-interruption programs. Law-enforcement officers were social distancing and policing less directly.

An increase in murders in many cities also corresponds closely to protests over the summer of 2020, though experts aren’t sure why. One theory is that police who were busy patrolling some of the largest protests in American history were not patrolling other streets. Officers also may have pulled back from policing, either as a counterprotest or as an attempt to respond to political pressures.