In recent years, gun violence in the United States has become an alarmingly common occurrence. From 2016, there has been over 10,000 homicides by firearm in the U.S. each year and firearms have been found to make up the majority of murder weapons in the country by far, demonstrating increasing rates of gun violence occurring throughout the nation. As of 2025, Mississippi was the state with the highest gun violence rate per 100,000 residents in the United States, at 29.4 percent, followed by Louisiana, at 28.1 percent. In comparison, Massachusetts had a gun violence rate of 3.7 percent, the lowest out of all the states. The importance of gun laws Gun laws in the United States vary from state to state, which has been found to affect the differing rates of gun violence throughout the country. Fewer people die by gun violence in states where gun safety laws have been passed, while gun violence rates remain high in states where gun usage is easily permitted and even encouraged. In addition, some states suffer from high rates of gun violence despite having strong gun safety laws due to gun trafficking, as traffickers can distribute firearms illegally past state lines. The right to bear arms Despite evidence from other countries demonstrating that strict gun control measures reduce rates of gun violence, the United States has remained reluctant to enact gun control laws. This can largely be attributed to the Second Amendment of the Constitution, which states that citizens have the right to bear arms. Consequently, gun control has become a highly partisan issue in the U.S., with 80 percent of Democrats believing that it was more important to limit gun ownership while 74 percent of Republicans felt that it was more important to protect the right of Americans to own guns.

As of September 2024, California had the most mass shootings in the United States, with 26 total shootings since 1982. The source defines a mass shooting as a shooting where three or more people were killed. Recently, a mass shooting occurred in the state of Maine on October 26, 2023, during which one of the highest number of fatalities from a mass shooting was recorded after Robert Card opened fire in a bowling alley and a bar, killing 18 and injuring 13 others. Firearms in the U.S. Mass shootings in the United States are disturbingly common. In comparison with other Western countries, there are significantly more shootings in the U.S., which some theorize is due to the relatively lax gun control laws. Gun control laws in the U.S. are dependent on the state, and the right to own a firearm is enshrined in the United States Constitution. Mass shootings The worst mass shooting in the U.S. was the Las Vegas Strip massacre in 2017, which resulted in 58 deaths and 546 injuries. 13 of the worst mass shootings in the United States have occurred since 2015 and the vast majority of these incidents in the U.S. have been carried out by shooters who are White and male.

THIS DATASET WAS LAST UPDATED AT 8:10 PM EASTERN ON MARCH 24

OVERVIEW

2019 had the most mass killings since at least the 1970s, according to the Associated Press/USA TODAY/Northeastern University Mass Killings Database.

In all, there were 45 mass killings, defined as when four or more people are killed excluding the perpetrator. Of those, 33 were mass shootings . This summer was especially violent, with three high-profile public mass shootings occurring in the span of just four weeks, leaving 38 killed and 66 injured.

A total of 229 people died in mass killings in 2019.

The AP's analysis found that more than 50% of the incidents were family annihilations, which is similar to prior years. Although they are far less common, the 9 public mass shootings during the year were the most deadly type of mass murder, resulting in 73 people's deaths, not including the assailants.

One-third of the offenders died at the scene of the killing or soon after, half from suicides.

About this Dataset

The Associated Press/USA TODAY/Northeastern University Mass Killings database tracks all U.S. homicides since 2006 involving four or more people killed (not including the offender) over a short period of time (24 hours) regardless of weapon, location, victim-offender relationship or motive. The database includes information on these and other characteristics concerning the incidents, offenders, and victims.

The AP/USA TODAY/Northeastern database represents the most complete tracking of mass murders by the above definition currently available. Other efforts, such as the Gun Violence Archive or Everytown for Gun Safety may include events that do not meet our criteria, but a review of these sites and others indicates that this database contains every event that matches the definition, including some not tracked by other organizations.

This data will be updated periodically and can be used as an ongoing resource to help cover these events.

Using this Dataset

To get basic counts of incidents of mass killings and mass shootings by year nationwide, use these queries:

Mass killings by year

Mass shootings by year

To get these counts just for your state:

Filter killings by state

Definition of "mass murder"

Mass murder is defined as the intentional killing of four or more victims by any means within a 24-hour period, excluding the deaths of unborn children and the offender(s). The standard of four or more dead was initially set by the FBI.

This definition does not exclude cases based on method (e.g., shootings only), type or motivation (e.g., public only), victim-offender relationship (e.g., strangers only), or number of locations (e.g., one). The time frame of 24 hours was chosen to eliminate conflation with spree killers, who kill multiple victims in quick succession in different locations or incidents, and to satisfy the traditional requirement of occurring in a “single incident.”

Offenders who commit mass murder during a spree (before or after committing additional homicides) are included in the database, and all victims within seven days of the mass murder are included in the victim count. Negligent homicides related to driving under the influence or accidental fires are excluded due to the lack of offender intent. Only incidents occurring within the 50 states and Washington D.C. are considered.

Methodology

Project researchers first identified potential incidents using the Federal Bureau of Investigation’s Supplementary Homicide Reports (SHR). Homicide incidents in the SHR were flagged as potential mass murder cases if four or more victims were reported on the same record, and the type of death was murder or non-negligent manslaughter.

Cases were subsequently verified utilizing media accounts, court documents, academic journal articles, books, and local law enforcement records obtained through Freedom of Information Act (FOIA) requests. Each data point was corroborated by multiple sources, which were compiled into a single document to assess the quality of information.

In case(s) of contradiction among sources, official law enforcement or court records were used, when available, followed by the most recent media or academic source.

Case information was subsequently compared with every other known mass murder database to ensure reliability and validity. Incidents listed in the SHR that could not be independently verified were excluded from the database.

Project researchers also conducted extensive searches for incidents not reported in the SHR during the time period, utilizing internet search engines, Lexis-Nexis, and Newspapers.com. Search terms include: [number] dead, [number] killed, [number] slain, [number] murdered, [number] homicide, mass murder, mass shooting, massacre, rampage, family killing, familicide, and arson murder. Offender, victim, and location names were also directly searched when available.

This project started at USA TODAY in 2012.

Contacts

Contact AP Data Editor Justin Myers with questions, suggestions or comments about this dataset at jmyers@ap.org. The Northeastern University researcher working with AP and USA TODAY is Professor James Alan Fox, who can be reached at j.fox@northeastern.edu or 617-416-4400.

In 2023, about 1,459 homicides were committed with the use of firearms in Texas. A further 1,334 homicides were committed with a firearm in California in that year. A ranking of the total number of murders by U.S. state can be found here.

As of July 22, 2024, there have been a total of 270 school shootings in California since 1966, the most out of any state. Texas had the second highest number of school shootings within this time period, with 225 shootings. The source defines a school shooting as every time a gun is brandished, fired, or a bullet hits school property for any reason, regardless of the number of victims (including zero), time, day or the week, or reason, including gang shootings, domestic violence, shootings at sports games and after hours school events, suicides, fights that escalate into shootings, and accidents.

From 2008 to March 6, 2024, the District of Columbia had the highest rate of school shootings nationwide, totaling around 0.7 school shootings per 100,000 residents. Louisiana, Delaware, Alabama, and Maryland rounded out the top five states with the highest school shooting rates relative to their populations. In contrast, there were no school shootings recorded in Montana, Wyoming, New Hampshire, Vermont, and Rhode Island within the provided time period. In addition to K-12 schools and college campuses, gun-related violence in the United States often occurs at workplaces, places of worship, and restaurants and bars.

The source defines school shootings as incidents of gun violence which occurred on school property, from kindergartens through colleges/universities, and at least one person was shot, not including the shooter. School property includes, but is not limited to, buildings, fields, parking lots, stadiums and buses. Accidental discharges of firearms are included, as long as at least one person is shot, but not if the sole shooter is law enforcement or school security.

Intentional homicides are estimates of unlawful homicides purposely inflicted as a result of domestic disputes, interpersonal violence, violent conflicts over land resources, intergang violence over turf or control, and predatory violence and killing by armed groups. Intentional homicide does not include all intentional killing; the difference is usually in the organization of the killing. Individuals or small groups usually commit homicide, whereas killing in armed conflict is usually committed by fairly cohesive groups of up to several hundred members and is thus usually excluded.

California reported the largest number of homicides to the FBI in 2023, at 1,929 for the year. Texas recorded the second-highest number of murders, with 1,845 for the year. Homicide victim demographics There were a total of 19,252 reported homicide cases in the U.S. in 2023. When looking at murder victims by gender and ethnicity, the vast majority were male, while just over half of the victims were Black or African American. In addition, homicide victims in the United States were found most likely to be between the ages of 20 and 34 years old, with the majority of victims aged between 17 to 54 years old. Are murders up? In short, no – since the 1990s the number of murders in the U.S. has decreased significantly. In 1990, the murder rate per 100,000 people stood at 9.4, and stood at 5.7 in 2023. It should be noted though that the number of homicides increased slightly from 2014 to 2017, although figures declined again in 2018 and 2019, before ticking up once more in 2020 and 2021. Despite this decline, when viewed in international comparison, the U.S. murder rate is still notably high. For example, the Canadian homicide rate stood at 1.94 in 2023, while the homicide rate in England and Wales was even lower.

In 2023, 76.37 percent of homicides were committed by firearm in the United States, compared to 85.7 percent in 2021. This figure has been increasing since 2014, when 63.6 percent of homicides were committed by firearm. Firearms in the United States Firearms in the United States have become a large part of American culture. The Second Amendment of the Constitution protects the right to keep and bear arms. This amendment has been cited as a reason why gun control laws should not become stricter. However, many Americans are in favor of stricter gun control laws due to the increase of shootings in the country. Handguns were the most frequently used weapon used on murder victims in 2020, and overall, the United States was the country with the highest rate of civilian-owned firearms. Who owns firearms? Firearms are more popular in certain parts of the United States than others. Texas was the state with the highest number of registered weapons in 2021, with Florida, Virginia, California, and Pennsylvania rounding out the top five. Firearm laws vary from state to state, which means it is easier to obtain a firearm in some states than in others. Gun owners in the United States are typically white, and men are more likely to personally own a gun than women.

Handguns are by far the most common murder weapon used in the United States, accounting for 7,159 homicides in 2023. This is followed by firearms of an unstated type, with 5,295 cases in that year. Why do murders happen in the U.S.? While most of the time the circumstances of murders in the U.S. remain unknown, homicides due to narcotics come in as the second most common circumstance – making them more common than, for example, gang killings. Despite these gruesome facts, the violent crime rate has fallen significantly since 1990, and the United States is much safer than it was in the 1980s and 1990s. Knife crime vs disease: Leading causes of death The death rate in the U.S. had hovered around the same level since 1990 until there was a large increase due to the COVID-19 pandemic in recent years. Heart disease, cancer, and accidents were the three leading causes of death in the country in 2022. The rate of death from heart disease is significantly higher than the homicide rate in the United States, at 167.2 deaths per 100,000 population compared to a 5.7 homicides per 100,000. Given just 1,562 murders were caused by knife crime, it is fair to say that heart disease is a far bigger killer in the U.S.

On October 1, 2017, the highest number of fatalities from a mass shooting in the United States was recorded when Stephen Paddock attacked a crowd of concert-goers on the Las Vegas strip, killing 58 and injuring 546 others, then taking his own life before authorities could apprehend him. Most recently, one of the worst mass shootings in the U.S. occurred in Maine on October 26, 2023, when Robert Card, an Army reservist and firearms instructor, opened fire in a bowling alley and a bar, killing 18 and injuring 13 others. Card then became the focus of a two-day-long manhunt, until he was found dead from a self-inflicted gunshot.

The USA Shooting Range Market is valued at USD 570 million, driven by a rising demand for personal and professional firearm training, fueled by increased interest in self-defense.

This study was conducted in an effort to better understand the circumstances surrounding murder cases in large urban areas. To evaluate the 75 largest counties in the nation, 33 counties were chosen. The ranking of these counties was based on a combination of crime data and population data. The criteria for including a case on a roster from which cases would be sampled was that (1) one or more defendants must have been arrested for murder and (2) the case must have been adjudicated during 1988. These cases were a sample of about half of all those in the 33 counties studied that had a murder charge brought to the prosecutors in 1988, or earlier, and that were disposed during 1988. When statistically weighted, the sample cases represent a total of 9,576 murder defendants in the nation's 75 largest counties. Demographic information on victims and defendants includes sex, date of birth, area of residence, and occupation. Variables are also provided on the circumstances of the crime, including the relationship between the victim and the defendant, the type of weapon used, the time of death, and the number of victims.

This table contains data on the rate of violent crime (crimes per 1,000 population) for California, its regions, counties, cities and towns. Crime and population data are from the Federal Bureau of Investigations, Uniform Crime Reports. Rates above the city/town level include data from city, university and college, county, state, tribal, and federal law enforcement agencies. The table is part of a series of indicators in the Healthy Communities Data and Indicators Project of the Office of Health Equity. Ten percent of all deaths in young California adults aged 15-44 years are related to assault and homicide. In 2010, California law enforcement agencies reported 1,809 murders, 8,331 rapes, and over 95,000 aggravated assaults. African Americans in California are 11 times more likely to die of assault and homicide than Whites. More information about the data table and a data dictionary can be found in the About/Attachments section.

The Division of Criminal Justice Services (DCJS) collects crime reports from more than 500 New York State police and sheriffs' departments. DCJS compiles these reports as New York's official crime statistics and submits them to the FBI under the National Uniform Crime Reporting (UCR) Program. UCR uses standard offense definitions to count crime in localities across America regardless of variations in crime laws from state to state. In New York State, law enforcement agencies use the UCR system to report their monthly crime totals to DCJS. The UCR reporting system collects information on seven crimes classified as Index offenses which are most commonly used to gauge overall crime volume. These include the violent crimes of murder/non-negligent manslaughter, forcible rape, robbery, and aggravated assault; and the property crimes of burglary, larceny, and motor vehicle theft. Police agencies may experience reporting problems that preclude accurate or complete reporting. The counts represent only crimes reported to the police but not total crimes that occurred. DCJS posts preliminary data in the spring and final data in the fall.

In 2023, the District of Columbia had the highest rate of murder and non-negligent manslaughter in the United States with a rate of 39 murders or non-negligent manslaughters per 100,000 inhabitants. Louisiana, New Mexico, Alabama, and Tennessee rounded out the top five states with the highest murder rates.

These data examine the effects on total crime rates of changes in the demographic composition of the population and changes in criminality of specific age and race groups. The collection contains estimates from national data of annual age-by-race specific arrest rates and crime rates for murder, robbery, and burglary over the 21-year period 1965-1985. The data address the following questions: (1) Are the crime rates reported by the Uniform Crime Reports (UCR) data series valid indicators of national crime trends? (2) How much of the change between 1965 and 1985 in total crime rates for murder, robbery, and burglary is attributable to changes in the age and race composition of the population, and how much is accounted for by changes in crime rates within age-by-race specific subgroups? (3) What are the effects of age and race on subgroup crime rates for murder, robbery, and burglary? (4) What is the effect of time period on subgroup crime rates for murder, robbery, and burglary? (5) What is the effect of birth cohort, particularly the effect of the very large (baby-boom) cohorts following World War II, on subgroup crime rates for murder, robbery, and burglary? (6) What is the effect of interactions among age, race, time period, and cohort on subgroup crime rates for murder, robbery, and burglary? (7) How do patterns of age-by-race specific crime rates for murder, robbery, and burglary compare for different demographic subgroups? The variables in this study fall into four categories. The first category includes variables that define the race-age cohort of the unit of observation. The values of these variables are directly available from UCR and include year of observation (from 1965-1985), age group, and race. The second category of variables were computed using UCR data pertaining to the first category of variables. These are period, birth cohort of age group in each year, and average cohort size for each single age within each single group. The third category includes variables that describe the annual age-by-race specific arrest rates for the different crime types. These variables were estimated for race, age, group, crime type, and year using data directly available from UCR and population estimates from Census publications. The fourth category includes variables similar to the third group. Data for estimating these variables were derived from available UCR data on the total number of offenses known to the police and total arrests in combination with the age-by-race specific arrest rates for the different crime types.

As of September 4, there were two mass shootings in the United States in 2024. This is compared to one mass shooting in 1982, one in 2000, and 12 mass shootings in 2022 and 2023. School shootings The United States sees the most school shootings in the world. Some motivations for school shootings included depression, seeking revenge, and bullying. As a result of the large amount of school shootings, gun control has become a central topic in U.S. politics. This widespread problem happens across the United States; however California saw the highest number of K-12 school shootings in the United States since 1970. However, the deadliest school shooting (as of October 2023) was the Virginia Tech massacre in 2007. This tragedy left 33 dead and 23 injured. Mass shooting issues Mass shootings happen when there are several injuries or deaths from a firearm-related violence. Throughout the last century, mass shootings have become an epidemic in the United States. However, despite the increase in mass shootings and number of casualties, the U.S. government has done little to prevent future shootings from happening. As a result of the lack of cooperation in politics, mass shootings have become an important issue for Generation Z living in the United States. Furthermore, having the right to bear arms is a popular belief in the U.S. and the percentage of households in the United States owning at least one firearm has remained somewhat steady since 1972.

GapMaps provides Crime Risk data sourced from Applied Geographic Solutions (AGS) which has been used by thousands of companies for over 20 years, providing valuable comparative information on the spatial patterns of crime.

Crime Risk Data includes crime risk indexes and projections on detailed crime types like murder and motor vehicle theft, and summary indexes of crimes against persons, crimes against property and overall crime risk. Crime Risk Data is available at the highly detailed census block level to capture the different risk levels across business and residential places. It is derived from an extensive analysis of several years of crime reports from the vast majority of law enforcement jurisdictions nationwide.

The crimes included in the Crime Risk Data database are the “Part 1” crimes and include murder, rape, robbery, assault, burglary, theft, and motor vehicle theft. These categories are the primary reporting categories used by the FBI in its Uniform Crime Report (UCR), with the exception of Arson, for which data is very inconsistently reported at the jurisdictional level. In accordance with the reporting procedures using in the UCR reports, aggregate indexes have been prepared for personal and property crimes separately, as well as a total index. While this provides a useful measure of the relative “overall” crime rate in an area, it must be recognized that these are unweighted indexes, in that a murder is weighted no more heavily than a purse snatching in the computation. For this reason, caution is advised when using any of the aggregate index values. In 2020, 5-Year Projections were added to the database.

Use cases: 1. Insurance underwriting and risk mitigation. 2. Evaluating the security measures needed to protect employees and customers at retail facilities. 3. The study of the effects of neighborhood crime on wellness and health care outcomes.

Methodology: Crime is tracked for multiple years using both FBI aggregate crime reports and for many parts of the country at the individual incident level. A complex set of statistical models are used to estimate and forecast risk of each individual crime type by using land use data in conjunction with demographic and business characteristics.

California led the way in gun safety in the United States as of January 2025, with a composite score of 90.5 based on the presence of 50 key gun safety policies. Massachusetts followed, with a score of 86.5, while Illinois rounded out the top three with a score of 85.5. Illinois joins the no-assault weapons club In 2023, Illinois came in seventh place for gun law strength; by 2024, this ranking rose to third, signifying that the state holds some of the strongest gun safety laws nationwide. However, this swift rise up the ranks also suggests that Illinois is still taking action against gun violence, particularly after seven people were killed and dozens were injured in a mass shooting in Chicago during a Fourth of July parade in 2022. In recent years, Illinois has consistently improved state legislation on gun safety and has enacted multiple measures to prevent further harm from firearms, including a statewide ban on assault weapons which was approved in January 2023. The Midwestern state joined eight other states, as well as Washington, D.C., which prohibits military-style weapons. Permissive open carry states dominate the bottom of the class Receiving less than five points each, Arkansas, Mississippi, and Idaho represent the lowest composite score for gun law strength nationwide. Arkansas, Mississippi, and Idaho are among the 25 U.S. states that do not require any permit to carry concealed guns in public, and are permissive open carry states as well. Moreover, these states do not require a permit or a background check to purchase a handgun and also neglect to necessitate any firearm safety training before making the purchase. Such gun safety laws are considered crucial to ensure that firearms are handled properly and do not cause anyone harm. However, it is also important to note that countries with strong safety measures may still experience high rates of gun violence due to illegal gun trafficking. As a result, taking legal action may not fully address all gun-related violence in the area, especially if there remains an illicit way for people to obtain a gun without restriction.