Citation

Webster DW. Ann. Intern Med. 2017; 166(10): 749.

Copyright

(Copyright © 2017, American College of Physicians)

DOI

10.7326/M17-0943

PMID

unavailable

Abstract

Mass shootings--particularly in public places--and the associated casualties have increased dramatically in the United States since 2004. Data collected on public mass shootings by Mother Jones magazine reveal a more than 3-fold increase in the number of people shot in these types of shootings between the years in which a federal ban on assault weapons and large-capacity ammunition feeding devices was in place (21.1 per 100 000 citizens per year in 1995 to 2004) and the years since the law expired (65.7 per 100 000 citizens per year in 2005 to 2016) (1). Yet, the direct effect on total firearm-related mortality remains small given that deaths from such shootings account for fewer than 2% of all firearm-related fatalities.

As Studdert and colleagues point out in their article, public mass shootings receive considerable news coverage and elevate public fear and anger (2). Using perhaps the most comprehensive data on handgun purchases available in the United States--a database maintained by the California Department of Justice--along with sophisticated analytic methods for time-series data, the researchers show that the most deadly and highly publicized mass shootings (in Newtown, Connecticut, and San Bernardino, California) were followed by increases in handgun purchases over 6 weeks of 53% and 41%, respectively.

Spikes in sales after high-profile mass shootings have been reported by some news outlets; however, the reporting has relied on convenience samples of retail gun sellers and data from presale background checks tracked by the Federal Bureau of Investigation, both of which can be poor barometers of firearm sales. Furthermore, the potential effect of mass shootings on gun sales is hard to gauge because it is impossible to know from aggregated background check data how many of the checks are for persons who already own 1 or more firearms versus those who may be spurred to buy a gun in response to concerns about mass shootings...

Language: en