Since 1994, the Brady Handgun Violence Prevention Act, the federal law requiring federally licensed gun dealers to conduct background checks before gun sales, has prevented more than three million felons, fugitives, and other prohibited purchasers such as people with disqualifying mental health conditions from purchasing firearms.

But many dangerous people have fallen through the cracks, including several perpetrators of mass shootings. Current federal law subjects gun buyers to background checks only if the seller is a licensed dealer “engaged in the business” of selling firearms.

Collectors and private sellers at gun shows and individuals who advertise weapons on the Internet are not required to vet their customers. Those who acquire weapons from acquaintances, friends, or family are also exempt from federal background checks.
As a result, 22 percent of U.S. gun owners who acquired their most recent firearm within the previous two years did so without a background check, according to a 2017 study in the Annals of Internal Medicine...…


To close these gaps, fifteen states and the District of Columbia now require gun buyers to obtain a license, certificate, or permit to purchase, as it is sometimes called, according to the Giffords Law Center to Prevent Gun Violence, a San Francisco-based nonprofit.