In 2020, the U.S. set a record of 610 mass shootings (defined as four or more people shot), more than double the total for 2014, and there has been a steady rise in the number and lethality of mass shootings since the 1980s. The problem has increased in gravity despite long-term improvements in emergency care and survival rates from bullet wounds, suggesting that without these advances the U.S. would be contending with even a more dire gun violence problem.

The proliferation of military-grade weaponry is undoubtedly a major factor in the rise of mass shootings, as weapons like the AR-15 and AK-47 have been used in many of the deadliest shootings. The current federal background check system has severe flaws, allowing many perpetrators of mass shootings to buy their weapons legally. In addition, more states need to adopt red flag laws that allow the seizure of weapons from those who have shown they pose a danger to the public or themselves.

While the U.S. stands out in its permissive gun laws, gun violence and mass shootings are also rooted in growing economic inequality and other concerning trends. While indiscriminate shootings in public or ideologically motivated shootings dominate the national media’s attention, by far the most common mass shootings occur in economically depressed communities of color as part of a dispute, whether targeted or spontaneous. 

An analysis for my book CARNAGE found that cities in which a high percentage of the population lives in distressed zip codes—areas with high poverty, high unemployment, little job growth, and many vacant residential units and business closings—tend to have higher homicide and mass shooting rates than cities in which most of the population lives in affluent neighborhoods. The 10 most distressed cities, such as Detroit, Cleveland, and Newark, N.J., had nine times the homicide rate per 100,000 people as the 10 most prosperous cities, such as San Francisco, Seattle, and Austin. 

Rust Belt cities like Chicago—84 mass shootings in 2019–2020—have seen the cratering of manufacturing jobs and the decline of businesses depending on factory workers, as well as a loss of population, leaving decaying neighborhoods with few prospects for those left behind.  While the predominantly Black south and west sides have been plagued by high rates of violence and residents have faced poverty and discriminatory housing practices for decades, some of these areas must contend with even more dire economic conditions today. 

Such conditions lead some men to join gangs and engage in illegal pursuits to meet financial and emotional needs. In these environments, gun carrying, illegal activity, and violent responses to provocation are often viewed as necessary for self-preservation and maintaining self-worth and dignity.

Another important factor in the growing mass shooting problem is the weakening community and institutional ties of youth. Civic engagement of youth, through political activities or church attendance, for example, is declining and young people report having fewer friends, enjoying less family time, spending more time alone, and spending hours a day on digital media. These trends are reflected in surging depression and suicide rates among youth. 

While most depressed individuals never contemplate a mass shooting, a U.S. Secret Service and Education Department study found that most school shooters had a history of suicide attempts or thoughts and a documented record of feeling extremely depressed or desperate.

Mass shootings have become normalized in this country. Shooters often lionize and emulate those coming before them. The contagious quality of shootings places a burden on media outlets covering a mass shooting to avoid specific content about the shooter and their motives that may lead impressionable individuals to identify with the shooter.

But it remains important to know why mass shooters commit these atrocities in order to prevent future ones. In distressed urban areas, shootings may stem from a simple provocation, insult, or even encroachment on the turf of another group. In such areas, measures are needed that emphasize conflict resolution and violence interruption. In addition, they need reforms that create hope through economic activity and educational opportunities, which allow people to preserve their dignity through prosocial activities rather than violence.

Thomas Gabor is a criminologist based in Florida. He is author of CARNAGE: Preventing Mass Shootings in America, which was published in March 2021, as well as several other books on gun violence.