The Excel file with detailed information on the 88 mass public shootings from 1998 through May 15, 2022 is available here. With all the discussion about having another assault weapon ban, only 14% of mass public shootings are done solely with any type of rifle. Twenty-nine percent involve only a rifle or a rifle in combination with a handgun and/or a shotgun. Among the other findings, about 9 in 10 of the attacks are in gun-free zones (though over the longer period from 1950, 94% of the attacks are in gun-free zones), half of the shooters are over age 30, and over 80 percent are at least 21 years of age. 97% are male, and 55% are white. Still, for many, it might be surprising that such a large percentage of these attackers are minorities and that most are much older than K-12 or college-age shooters. Earlier work that we had done showed that the vast majority of these killers have no religious or political views. 48% of the mass public shooters were seeing mental health care professionals prior to their attacks.
While the majority of mass public shooters are white, they are much less than their share of the US population. Including people of Middle Eastern descent, about 76 percent of Americans were white over this period, but 63% of the mass public shooters were white (just 55% are white if you exclude people of Middle Eastern descent). About 3.7 million are Arab Americans and 6.5 million are Jewish Americans, so while 8% of shooters are of Middle Eastern Arab descent, they make up just over 1% of the US population.