This week, newly dominant House Democrats announced legislation that would require all gun buyers go through a background check, regardless of whether they buy a weapon from a licensed dealer, collector at a gun show, or stranger in a parking lot. Universal background checks are popular. A Quinnipiac University poll after the school shooting in Parkland, Fl., last February found that 97 percent of voters approved of the policy. Evidence that checks reduce crime is more complicated than the political momentum might suggest, The Trace reports. “The direct evidence on effectiveness is limited,” said Duke University public policy expert Philip Cook. “It’s very plausible that a state that tries to close this huge loophole and devotes resources to enforcing it will have good results. But not every program is going to be equally effective.”
Federal law subjects a gun sale to a background check only if the seller is a licensed dealer. Collectors who set up booths at gun shows or individuals who advertise a few weapons on a classifieds website don’t have to vet their customers. Some states require all gun transactions to go through a check. Twenty states and the District of Columbia regulate private sales, either by mandating checks at the point of every sale or by requiring permits to purchase a firearm. A survey by Harvard and Northeastern universities in 2017 found that one of five guns is sold in an unregulated transaction. A U.S. Bureau of Justice Statistics report issued Thursday said that among prisoners who possessed a gun during their offense, 90 percent did not obtain it from a retail source. More than half (56 percent) had stolen it, found it at a crime scene, or obtained it off the street or from the underground market Fewer than 1 percent obtained the firearm at a gun show.