PolitiFact PolitiFact Sheet: 3 things to know about the ‘gun show loophole’ Professors at Northeastern and Harvard universities conducted a gun survey in 2015 that isn’t yet published. The national survey of 4,000 non-institutionalized adults found that 22 percent of the people who purchased guns — at gun shows, stores or elsewhere — underwent no background check, said Matthew Miller, professor of Health Sciences and Epidemiology at […]