At Mother Jones, where I work as an editor, we have compiled an in-depth, open-source database covering more than three decades of public mass shootings. By our measure, there have been four “mass shootings” this year, including the one in San Bernardino, and at least 73 such attacks since 1982.
What explains the vastly different count? The answer is that there is no official definition for “mass shooting.” Almost all of the gun crimes behind the much larger statistic are less lethal and bear little relevance to the type of public mass murder we have just witnessed again. Including them in the same breath suggests that a 1 a.m. gang fight in a Sacramento restaurant, in which two were killed and two injured, is the same kind of event as a deranged man walking into a community college classroom and massacring nine and injuring nine others. Or that a late-night shooting on a street in Savannah, Ga., yesterday that injured three and killed one is in the same category as the madness that just played out in Southern California.