Sociologist Joel Best provides a history of how American scholars and media have classified mass shootings:

It may seem self-evident that the killings at Sandy Hook Elementary ought to be classified as a shooting event, or as a school shooting or a mass shooting. Of course we classify events into categories that make sense to us, and it is easy to take familiar categories for granted. We learn of terrible crimes and we are accustomed to commentators talking about incidents as instances. But the ways we make sense of the world—the terms we use to describe that world—are created by people, and they are continually evolving, so that specific categories come into and fall out of favor. In fact, in recent decades, Americans have understood events like the Newtown killings in a variety of ways…

By the early 1980s, the Federal Bureau of Investigation promoted the distinction between mass murder and serial murder. The Bureau had a new databank—the Violent Criminal Apprehension Program, or VICAP—that could help law enforcement identify similar crimes that had occurred in other jurisdictions. But in the aftermath of revelations about the FBI’s surveillance of the civil rights movement, an effort to expand the bureau’s domestic data collection invited suspicion and resistance. The FBI used the serial murderer menace—and particularly the idea that serial killers might be nomadic, able to kill in different jurisdictions without the authorities ever recognizing that crimes in different places might be linked—to justify the VICAP program. That set the stage for Clarice Starling and all the other heroic FBI agents who began pitting their wits against serial murderers in crime fiction and movies. “Son of Sam” would no longer be classified with Charles Whitman…

Journalists notice patterns, so similarities between cases invite the creation of new categories. For example, in 1986, a postal worker killed 14 postal employees; then, in 1991, there were two more incidents involving former postal workers killing employees at post offices. This led to the expression going postal. Eventually, after further incidents in 1993, the Postal Service responded with a program to improve their workplace and prevent violence. Some criminologists began writing about workplace violence, although this category was defined as including any violence in a workplace, not just mass murders. Under that definition, a large share of workplace violence involved robberies. (According to one analysis, the three most common sites for workplace violence were taxicabs, liquor stores, and gas stations—all isolated settings likely to have cash on hand.)

At the end of the 1990s, attention shifted to schools. During the 1997–98 academic year, there were heavily publicized incidents in West Paducah, Kentucky; Jonesboro, Arkansas; and Springfield, Oregon. The Jonesboro story made the cover of Time, which featured a photo of one of the shooters as a young child wearing camouflage and holding a rifle, with the caption “Armed & Dangerous.” Thus, the expression school shooting was already familiar a year before the April 1999 killings at Columbine. Advocates and academics began compiling databases of school violence, although the results were surprising: The average number of deaths per year fell, from 48 during the period from the fall of 1992 through the spring of 1997, to 32 during the period spanning September 1997 through the end of the school year in 2001, even though Columbine and the other best-publicized cases occurred during the latter period. In spite of commentators declaring that the nation was experiencing a wave or epidemic of school shooting, the evidence suggested that violent deaths in schools were declining.

Best has written a lot about how social categories, experiences, and data then get used in political and civic discussions. The classification as a school shooting or the result of mental illness then shapes the rest of the discussion including what should be done in the future. Social problems can’t be social problems until they can be shown to be worth the public’s attention.

What Best doesn’t do is try to forecast how the Newtown shooting will come to be known in the future. What is the dominant narrative that will develop? And how will it be used?