U.S. Mass Killings in 2025 Drop to Lowest Level Since 2006: Experts Analyze the Decline

A shooting at a children's birthday celebration in California that resulted in four fatalities marks the 17th mass killing of the year—the lowest number documented since 2006, according to a database collaboratively maintained by The Associated Press, USA Today, and Northeastern University.

Experts caution that this decline doesn't necessarily indicate a permanent improvement in public safety, but may simply represent a return to average levels after previous spikes.

"Sir Isaac Newton never studied crime, but he says 'What goes up must come down,'" noted James Alan Fox, a criminologist at Northeastern University. He suggests the current reduction is likely what statisticians term a "regression to the mean," signifying a return to more typical crime patterns following unusual increases in mass killings during 2018 and 2019.

"Will 2026 see a decline?" Fox questioned. "I wouldn't bet on it. What goes down must also go back up."

Mass killings—defined as incidents where four or more individuals are killed within a 24-hour period, excluding the perpetrator—are tracked in a database maintained through a partnership between The Associated Press, USA Today, and Northeastern University. Fox, who manages this database, reports that mass killings decreased approximately 24% this year compared to 2024, which itself represented about a 20% reduction from 2023.

The rarity of mass killings leads to statistical volatility, explained James Densley, a professor at Metropolitan State University in Minnesota.

"Because there's only a few dozen mass killings in a year, a small change could look like a wave or a collapse," when it's actually just a return to more typical frequencies, Densley explained. "2025 looks really good in historical context, but we can't pretend like that means the problem is gone for good."

Several factors may be contributing to the decrease, Densley suggested, including an overall decline in homicide and violent crime rates that peaked during the COVID-19 pandemic. Improvements in immediate response protocols for mass shootings and other mass casualty incidents might also play a significant role.

"We had the horrible Annunciation School shooting here in Minnesota back in August, and that case wouldn't even fit the mass killing definition because there were only two people killed but over 20 injured," Densley noted. "But I happen to know from the response on the ground here, that the reason only two people were killed is because of the bleeding control and trauma response by the first responders. And it happened on the doorsteps of some of the best children's hospitals in the country."

Crime patterns are complex, and academics face challenges in determining precise reasons behind crime rate fluctuations, according to Eric Madfis, a criminal justice professor at University of Washington-Tacoma.

"It's multi-causal. It's never going to be just one thing. People are still debating why homicide rates went down in the 1990s," Madfis observed. "It is true that gun violence and gun violence deaths are down, but we still have exceedingly high rates and numbers of mass shootings compared to anywhere else in the world."

An increasing number of states are allocating funding for school threat assessments, with 22 states recently mandating this practice, which could be preventing some school shootings, though its impact wouldn't extend to mass killings in other settings. None of the mass killings recorded in the database for 2025 occurred in schools, with only one school-based mass killing documented in 2024.

Approximately 82% of this year's mass killings involved firearms. Since 2006, mass killings have claimed 3,234 lives—81% of these victims died from gunshots.

Christopher Carita, formerly a detective with the Fort Lauderdale Police Department and currently a senior training specialist with gun safety organization 97Percent, highlighted that the Safer Communities Act passed in 2022 provided millions in funding for gun violence prevention programs. Various states utilized these resources differently—some establishing social support systems for individuals at risk of committing violence, others enhancing law enforcement and threat assessment capabilities. This flexibility has been instrumental in reducing gun violence rates, he indicated.

"It's always been framed as either a 'gun problem' or a 'people problem' and that's been very contentious," Carita remarked. "I feel like for the first time, we're looking at gun violence as a 'both, and' problem nationally."

Concentrating exclusively on extreme events like mass killings risks "missing the forest for the trees," cautioned Emma Fridel, an assistant professor of criminology at Florida State University. "If you look at the deaths from firearms, both in homicides and suicides, the numbers are staggering. We lose the same number of people every year to gun violence as the number of casualties we experienced in the Korean war. The number one cause of death for children is guns.

"Mass killings should be viewed as one part of the issue, rather than the outcome of interest," she concluded.