Mass Shootings in the United States: 2009-2016

April 11, 2017

Using FBI data and media reports, Everytown for Gun Safety developed an analysis of mass shootings that took place between January 2009 and December 2016.

Executive Summary

At around 11:30 PM on Saturday, July 26, 2014, neighbors of the Smith family in Saco, ME heard gunshots ring out. Maine State Police detectives arrived at the Smiths’ apartment to discover five bodies, all fatally shot. Finding a shotgun under Joel Smith’s body, police quickly identified the scene as a murder-suicide: Smith had shot and killed his wife Heather, their two children, and his stepson before turning the gun on himself.

There were several warning signs in advance of the shooting that suggested the Smith family was in danger. After the shooting, Joel’s father told police that his son was a heavy drinker and often used alcohol to cope with depression. And a family friend of the Smiths told police that, just days before the shooting, Heather confided that Joel had pointed a gun at his own head and threatened to kill himself.Bangor Daily News. Father of Saco man who murdered family says son was fighting alcoholism. Published August 1, 2014. Accessed February 15, 2017.

Scene from Saco, ME

The story of the Smith family is devastating. But when it comes to mass shootings in the United States—incidents in which four or more people are shot and killed, not including the shooter—it fits a familiar pattern. Like the shooting of the Smith family, the majority of mass shootings in the United States are related to domestic or family violence. Furthermore, there are often warning signs in advance of these shootings—“red flags” indicating that the shooters posed a risk to themselves or others.

To better assess the reality of mass shootings in the United States—and to identify policies which could prevent them from occurring in the first place—Everytown analyzed every mass shooting we were able to identify in the United States from 2009-2016. This analysis uncovered the following findings:

1 in 4 Deaths in a mass shooting is a child

  • From 2009-2016 in the U.S., there have been 156 mass shootings—incidents in which four or more people were shot and killed, not including the shooter. These incidents resulted in 1,187 victims shot: 848 people were shot and killed, and 339 people were shot and injured. In addition, 66 perpetrators killed themselves after a mass shooting, and another 17 perpetrators were shot and killed by responding law enforcement.
  • The majority of mass shootings—54 percent of cases—were related to domestic or family violence.
  • Mass shootings significantly impacted children: 25 percent of mass shooting fatalities (211) were children. This is primarily driven by mass shootings related to domestic or family violence, in which over 40 percent of fatalities were children.
  • In nearly half of the shootings—42 percent of cases—the shooter exhibited warning signs before the shooting indicating that they posed a danger to themselves or others. These red flags included acts, attempted acts, or threats of violence towards oneself or others; violations of protective orders; or evidence of ongoing substance abuse.
  • More than one-third of the shootings—34 percent—involved a shooter who was prohibited from possessing firearms.
  • Only ten percent of incidents took place in “gun-free zones”, or areas where civilians are prohibited from carrying firearms and there is not a regular armed law enforcement presence (armed security guards, for example). The vast majority of incidents—63 percent—took place entirely in private homes.

These findings reaffirm the value of gun violence prevention policies that address the circumstances underlying mass shootings: strong domestic violence laws that keep guns away from abusers, mechanisms that allow for the temporary removal of guns from individuals who have exhibited dangerous recent behavior, and background checks on all firearm sales to prevent people who are prohibited from having guns from buying them.


Everytown defines a mass shooting as an incident in which four or more people, not including the shooter, are killed with a firearm. The threshold of four fatalities—which is used by the majority of academics and organizations studying mass violence—is derived from a definition of mass murder used in a 2005 FBI report.FBI. Serial Murder: Multi-Disciplinary Perspectives for Investigators. 2005. Accessed February 15, 2017. Unless specifically noted, the casualty figures discussed below include only victims and not perpetrators who were also killed or injured.

To identify the 156 mass shootings included in this analysis, Everytown pulled information from the FBI’s Supplementary Homicide Report and from media reports. Everytown then requested police and court records for each shooting. Researchers received official records for 76 shootings. If police or court records were unavailable, Everytown used media reports that were deemed reliable for additional case information.


Domestic violence is a driving factor in mass shootings

The majority of mass shootings in the U.S. are related to domestic or family violence. In at least 54 percent of mass shootings (85), the perpetrator shot a current or former intimate partner or family member. These domestic violence mass shootings resulted in 422 victims being killed—more than 40 percent (181) of whom were children. A majority of these cases—56—also ended with the perpetrators killing themselves.

Included in this count are Phoukeo Dej-Odoum and her three children. On June 8, 2016, Phoukeo Dej-Odoum applied for a temporary protective order in Clark County, NV, noting that her husband had threatened the family with weapons in the past. The next day, her application was denied—reportedly because the threats referenced were not recent enough. On June 18, she quit her job as an assistant manager at Sport Clip Haircuts, texting her boss, “I cannot work. [My husband will] know where I am. I have to quit now.”Las Vegas Review-Journal. Mother killed in quadruple murder-suicide of family had quit work, was ‘scared for her life’. Published July 1, 2016. Accessed February 15, 2017. On June 29, the husband, Jason Dej-Odoum, chased Phoukeo through a Walgreens parking lot, where he shot and killed her. Hours later, when police went to the family home looking for Jason, they found the couple’s three children—ages 9 to 15—dead. Jason had shot and killed them. Jason was there too, dead from a self-inflicted gunshot wound.

Weeks after applying for a protective order, Phoukeo Dej-Odoum was shot and killed by her husband in a Walgreens parking lot.

The connection between mass shootings and domestic violence may be explained, in part, by the role guns play in domestic violence generally. About 4.5 million American women report that they have had an intimate partner threaten them with a gun.Sorensen S, Schut R. Nonfatal Gun Use in Intimate Partner Violence: A Systematic Review of the Literature. Trauma, Violence, & Abuse. 2016. Accessed February 15, 2017. And guns make it more likely that domestic abuse will turn fatal—when a gun is present in a domestic violence situation, the likelihood that a woman will be shot and killed increases fivefold.Campbell JC, Webster D, Koziol-McLain J, et al. Risk Factors for Femicide in Abusive Relationships: Results From a Multisite Case Control Study. American Journal of Public Health. 2003; 93, 1089-1097.93

Because of the risk that firearms pose when they intersect with domestic violence, a series of federal and state laws are in place to help keep guns out of the hands of domestic abusers. The strongest state laws prohibit domestic abusers and stalkers from buying or possessing guns, require background checks for all gun sales, and create processes to ensure that abusers and stalkers relinquish guns already in their possession. When these laws are on the books and enforced properly, they save lives. For example, cities in states that restrict access to firearms for those under domestic violence protective orders see a 25 percent reduction in intimate partner gun deaths.Zeoli A, Webster D. Effects of Domestic Violence Policies, Alcohol Taxes and Police Staffing Levels on Intimate Partner Homicide in Large U.S. Cities. Journal of Injury Prevention. 2010; 16(2), 90-95. Accessed February 15, 2017.

There were often warning signs before mass shootings

In the aftermath of a mass shooting, survivors, the community, and policymakers try to understand whether the shooting could have been prevented. In pursuit of this goal, public health experts that study mass shootings and other acts of mass violence have identified certain dangerous behaviors that can serve as warning signs that an individual is a risk to themselves or others.Consortium for Risk-Based Firearm Policy. Guns, Public Health, and Mental Illness: An Evidence- Based Approach for State Policy. Accessed February 15, 2017. These “red flags” include, but are not limited to recent acts, attempted acts, or threats of violence towards oneself or others; a violation of a protective order; or evidence of ongoing substance abuse.For this analysis, dangerous behaviors that would qualify as a “red flag” include any of the following, if observed within 3 years of the shooting: a recent threat of violence, act of violence or attempted act of violence towards self or others; a conviction for certain firearms offenses (including unlawful and reckless use, display or brandishing); a violation of a protective order; evidence of ongoing abuse of controlled substances or alcohol.

Shooter exhibits dangerous warning signs

In nearly half of mass shootings—42 percent of cases—the shooter exhibited at least one red flag prior to the shooting.

This was true in the case of Omar Mateen who, on July 12, 2016, fatally shot 49 people and injured 53 more at Pulse, a gay nightclub in Orlando. Before this attack, there were warning signs that he was potentially dangerous. His ex-wife had alleged that he beat her: “He would just come home and start beating me up because the laundry wasn’t finished or something like that.”The Washington Post. ‘He was not a stable person’: Orlando shooter showed signs of emotional trouble. Published June 12, 2016. Accessed February 15, 2017. A man who had recently been his colleague said, “He [Mateen] was an angry person, violent in nature…I saw it coming…He said he was going to kill a whole bunch of people.”CNN. Omar Mateen: Angry, violent ‘bigot’ who pledged allegiance to ISIS. Published June 14, 2016. Accessed February 15, 2017.

The fact that so many mass shooters displayed warning signs prior to the shootings indicates the value of providing a mechanism to law enforcement or family members that would allow them to petition a court to temporarily remove firearms from an individual they believe to be at risk to themselves or others.

This is what policymakers refer to as a Gun Violence Restraining Order (GVRO), or in some cases an Emergency Risk Protection Order (ERPO). Currently, four states—California, Connecticut, Indiana, and Washington—have such restraining order processes in place. These provide a crucial tool for intervention when a person exhibits dangerous behaviors.Cal. Penal Code § 18100, et. seq.; Conn. Gen. Stat. § 29-38c; Ind. Code § 35-47-14-1, et. seq.;Rev. Code Wash. § 7.94.010, et. seq.

Many shooters were prohibited from possessing firearms

Policymakers have long recognized that it’s dangerous for felons, domestic abusers, or those with serious mental illnesses to have guns. That is why people with such records are legally prohibited from buying or possessing firearms.

The harm posed when guns get into the wrong hands is particularly evident in mass shootings. In more than one-third—34%—of mass shootings (53), the shooter was prohibited from possessing firearms at the time of the shooting.

The federal background check system is designed to enforce legal prohibitions and keep guns out of the hands of dangerous people. Under federal law, licensed dealers are legally required to run a background check on potential buyers. When someone who is not legally allowed to have a gun attempts to make a purchase from a licensed dealer, the background check stops the sale. In fact, between 1994-2016, the background check system has blocked over 3 million gun sales to prohibited purchasers.Karberg JC, Frandsen RJ, Durso JM, et al. Background Checks for Firearm Transfers, 2013-2014. Bureau of Justice Statistics. Published June 2016. Accessed February 15, 2017. Data for 2015 and 2016 were obtained by Everytown from the FBI directly. Though majority of the transactions and denials reported by FBI and BJS are associated with a firearm sale or transfer, a small number may be for concealed carry permits and other reasons not related to a sale or transfer.

But there’s a loophole in the federal system. Federal law only requires background checks for gun sales at licensed dealers—a gap referred to as the unlicensed sale loophole. Nineteen states and Washington, DC have acted to close this dangerous loophole by requiring background checks on all handgun sales.CA, CO, CT, DE, HI, IA, IL, MD, MA, MI, NE, NV, NJ, NY, NC, OR, PA, RI, and WA. There is strong evidence that closing this loophole saves lives. In states that have done so, 47 percent fewer women are shot to death by their intimate partners, 53 percent fewer law enforcement officers are killed with guns, and there is 48 percent less gun trafficking in cities.Everytown for Gun Safety. Background checks prevent gun violence and save lives. http://every. tw/1U6gEd0. Accessed February 15, 2017.

Shooter was prohibited from possessing firearms

In the absence of laws that close the unlicensed sale loophole, criminals and other prohibited people can easily avoid background checks simply by buying guns from unlicensed sellers—including strangers they meet online.

This is exactly how convicted felon Jody Lee Hunt was able to buy the firearm he used to shoot and kill four people on December 1, 2014 in Morgantown, WV. Fifteen years before the shooting, he had been convicted of felony kidnapping and sentenced to ten years in prison for abducting a former girlfriend and holding her hostage at gunpoint. As a result of the conviction, he became prohibited from buying and possessing firearms. If he had tried to purchase a firearm at a licensed dealer, a background check would have stopped the sale. But West Virginia law does not require background checks for gun sales between individuals who are not licensed dealers. So Hunt found a 9mm handgun listed for sale on Facebook and purchased it from a fellow West Virginian who had posted the ad.

He then used the gun to shoot and kill four people: a business rival, an ex-girlfriend and her boyfriend, and his cousin. Finally, he used the same gun to shoot and kill himself.

Most mass shootings do not occur in gun-free zones

10% of Mass Shootings take place in Gun-Free zones

The gun lobby frequently claims that so-called “gun-free zones”—areas where civilians are prohibited from carrying firearms and there is no regular armed law enforcement present—attract mass shooters. This does not seem to be the case. In fact, only 10 percent of mass shootings (16) took place in so-called “gun-free zones”. The vast majority of mass shootings—63 percent—took place entirely in private homes.

Additionally, there is not a single mass shooting in Everytown’s database in which the shooter was stopped by an armed civilian—even in cases where there were armed civilians present.

Take, for example, the October 1, 2015 mass shooting in which Christopher Harper-Mercer fatally shot nine people in an attack at Umpqua Community College in Roseburg, OR. At the time of the shooting, there were several students carrying concealed handguns on campus. But they recognized that an attempt to provide help may have confused law enforcement and decided not to intervene. As one student, a military veteran who was carrying a concealed gun at the time, explained: “Luckily, we made the choice not to get involved…not knowing where SWAT was on their response time, they wouldn’t know who we were, and if we had our guns ready to shoot, they’d think we were the bad guys.”Think Progress. ‘Good Guy With A Gun’ Was On UCC Campus At Time Of Massacre. http://bit. ly/2kUGaYM. Published October 2, 2015. Accessed February 15, 2017.


Mass shootings have a devastating impact on our communities‐from the victims killed, to the surviving witnesses, to the public at large. In order to prevent such tragic violence in the future, we must understand how and why these incidents unfold.

The true picture of mass shootings in the U.S. is different than headlines suggest. While there are prominent attacks on public places—like the Pulse nightclub in Orlando—the majority of these shootings occur in the home, between spouses, partners, and family members. Furthermore, the fatalities documented in this report were not unavoidable. Often, the shooters never should have had access to a gun in the first place—either because they were prohibited from possessing firearms or they had recently exhibited dangerous behavior. Policymakers across the country should examine their state’s current laws, and address the gaps that make it too easy for dangerous individuals to arm themselves. This involves requiring background checks on all gun sales; ensuring that domestic abusers do not have access to firearms; and creating mechanisms that allow for the temporary removal of guns from individuals who have demonstrated a risk to themselves or others.


Click here to download an appendix of the shootings profiled in this analysis.