Mass shootings are the most public and devastating acts of firearm violence. They also tend to capture the most attention, outrage and extensive news coverage, despite making up a very small percentage of overall gun deaths.
Because mass shootings are a relatively new phenomenon in this century, there’s no official or standard definition for a mass shooting. As a result, a variety of definitions have been created by news organizations, researchers and law enforcement agencies.
“We know what a category five hurricane is. We know what a 6.0 on the Richter scale is. We know what stage four cancer is, but we don’t have parameters for [mass shootings],” said Jennifer Mascia, a writer and founding member of The Trace, during a recent panel discussion.
“Which seems strange because we have lived through a decade of one catastrophic mass shooting after another,” she added.
The definition of a mass shooting varies due to a number of factors, including:
- different minimum number of victims;
- whether the victim count includes or doesn’t include people who were injured but not killed;
- where the shooting occurred
- whether the shooting was in connection to another crime;
- the relationship between the shooter and the victims.
Understanding what a mass shooting is will help to improve coverage of these events but also serves as a reminder for newsrooms to consider how they define them and how much coverage they warrant. When covering mass shootings, journalists should — at the very least — include the larger context, which is that these events continue to be relatively rare while firearm suicides and homicides make up the vast majority of gun deaths.
The communities most often impacted by mass shootings also rarely receive complete and humanizing coverage. When covering mass shootings, we should also be conscious that the U.S. news media are frequently biased when covering them.
A range of definitions
Mascia, who’s also a contributor for CNN’s Guns in America project, recently broke down the contradicting definitions for a mass shooting during a webinar with the National Press Club Journalism Institute.
In 2013, Congress defined a mass killing as three or more killings in a single incident. It established that definition to give the attorney general authority to investigate these incidents following the Sandy Hook shooting in Newtown, Conn., Mascia said. But that metric leaves out the type of weapon used and does not account for injuries.
At the state level, Mascia continued, only New York and Texas have official definitions for mass shootings, though both are relatively new. The CDC has gun death figures, but doesn’t specify which were part of a mass shooting. And the FBI’s crime data is reported voluntarily by states, leading to inconsistent and incomplete data.
The FBI also doesn’t have a mass shooting definition, but the agency defines a mass killing as four or more people killed in a single event. However, that definition leaves out shootings where many people are wounded but not killed, Mascia pointed out.
“So that leaves the media … to figure out what to call it when someone shoots multiple people,” Mascia said. “The easiest thing for journalists to do is to defer to a legal definition, but we can’t. So in the absence of one, media outlets are left to their own devices, and there’s no agreed upon definition there.”
The Washington Post and AP use the FBI’s mass killing definition. So by that standard, 41 mass gun murders happened in 2023, more than double the 17 that happened in 2013, Mascia said.
But organizations like the Gun Violence Archive use a broader definition: A mass shooting is four people shot regardless of whether they survive and does not count the perpetrator. By that standard, around 600 mass shootings happen each year. CNN and the BBC are among the more prominent outlets that cite the Gun Violence Archive.
Per the Gun Violence Archive, there were 656 mass shootings in 2023. “So that describes the problem as very massive,” Mascia said.
Then, the definition gets even narrower for other news outlets and the Violence Project, which tracks mass shootings. The Project defines a mass shooting as a shooting that takes place in public and is not connected to domestic violence or street violence, leaving out family annihilations.
By that metric, only eight mass shootings happened last year.
“Many mass shootings begin as domestic shootings. So even their narrower definitions failed to capture the whole story, which is that it could begin as personal violence, but the public still bears a cost because the shootings move into the public realm,” Mascia said.
While mass shootings are the most visible manifestation of gun violence, they only accounted for 1.5% of gun deaths in 2023, Mascia said, citing the Gun Violence Archive. Suicides made up 56% while the rest were homicides, unintentional shootings and police shootings.
“When our gun violence coverage is led by mass shootings,” Mascia said, “we are not seeing the big picture.”
Understanding bias
Mass shootings occur regularly in Black and poor neighborhoods. Yet those incidents rarely receive the same coverage as mass shootings in which the victims are largely white and wealthier, which are much more uncommon.
For example, a January 2026 UC Davis study found that mass shootings in majority-white neighborhoods received roughly twice the news coverage of those that happen in neighborhoods largely made up of people of color.
The researchers — from University of California, Davis, Northwestern University and the University of Washington — analyzed nearly 36,000 news stories reporting on individual shootings.
They found significant differences in the volume of coverage and characterization of the shootings based on the neighborhood where the incidents occurred and their racial and ethnic composition.
Reporting tips
Covering mass shootings requires careful, measured reporting, both when it’s breaking news and in follow-up coverage. Here are some best practices to keep in mind:
- Humanize the victims. And be respectful when reaching out to loved ones and survivors. Respect their boundaries and avoid swarming survivors. Give them plenty of space. Do not pressure them to talk because of your deadline. Instead, offer to connect later. These practices are also a way to minimize retraumatization. Survivors often feel exploited by the media coverage following a mass shooting.
There are plenty of good examples of stories where the victims were humanized. The Austin American-Statesman wrote about the 19 children and two teachers killed at Uvalde Elementary School. The Los Angeles Times also recently wrote about the one-year anniversary of the Lunar New Year mass shooting in Monterey, Calif. that killed 11 people. Remember to get the full story of who the victims were. And don’t forget about surviving victims, whether they were shot or witnessed the incident. They have stories worth telling, too. The L.A. Times story highlights survivors and the victims and their families.
- When writing about the suspect, focus on how they gained access to the weapon they used and whether or not they were a known threat to law enforcement. Try to avoid the “Well, his neighbor didn’t really know him but he thought he was a normal guy.” angle. In general, it’s important to center the victims and the community impacted and avoid centering the perpetrator.
- Remember to include some of the larger context outlined in this tip sheet, including the facts that deaths and injuries from mass shootings make up a very tiny percentage of overall gun deaths and injuries. It’s also important to localize those numbers to the state and local levels when relevant.
- Before your newsroom inevitably has to cover another mass shooting, have a discussion about how your organization defines one and explain your choice to your audience. Will your newsroom use the FBI’s mass killing definition, like the AP? Or the Gun Violence Archive’s definition, like CNN?
Resources
- The Trace is the only newsroom dedicated to exclusively covering gun violence. They’re the premier resource for reporting on gun violence, especially for contextualizing mass shootings, as they do in this story.
- RAND’s Gun Policy in America offers a wide array of analysis and research on gun violence, including this essay on mass shootings from 2021.
- Contact: Warren Robak, senior media relations advisor, Warren_Robak@rand.org.
- The Violence Project, as mentioned earlier, is a nonprofit and nonpartisan research center that maintains a database on mass shootings and mass shooters. Their data on mass public shootings extends from 1966 to the present.
- Contact: violence-prevention@hamline.edu
- The Pew Research Center recently published this deep dive on 2023 gun death data, including a detailed section on mass shootings.
- It’s often promoted on this page, but the Gun Violence Archive is always a great resource on near-real-time gun violence data.
Editor’s Note: This is an updated version of a story originally posted on March 11, 2024.
