Historic gun sales and the 2020 murder spike.

Yesterday, we (The Trace) highlighted a new analysis of the role the pandemic and police violence played in last year's homicide rise. Authors Jeff Asher and Rob Arthur also probed the connection between record gun sales and the surge. Citing ATF estimates that 10 percent of guns are used in a crime within six months of purchase, they estimate that a year-over-year increase of 5 million gun sales in the first half of last year meant approximately half a million more were available for use in crimes in the last half of 2020. What that could mean:
A jump in crimes committed using guns: That’s what their data showed in several cities, including Chicago and Los Angeles. In other cities, gun seizures increased amid declines in other kinds of arrests. “So what you see is that as gun availability increases, a higher percentage of the crimes are committed with guns, and as a result there are more deaths than there would be otherwise,” Philip Cook, a professor emeritus of public policy at Duke University, tells the authors.
A caveat on more gun availability: Arthur and Asher note that the government releases delayed crime data and that the “ATF does not track the chain of custody from a gun’s initial purchase through subsequent secondhand purchases or thefts into use in a crime, making it impossible to know exactly how surges in gun purchases translate into greater availability of firearms among those who use them to commit crimes.”