How to Stop Mass Shootings

Gun violence in K-12 schools in the United States: Moving towards a preventive (versus reactive) framework

Intentional shootings in K-12 schools in the U.S. persist as a public health problem. The number of shootings in K-12 schools has increased precipitously since 2017. And with approximately 100,000 K-12 public schools nationally serving 51 million children, investing in a comprehensive gun violence prevention strategy is critical. Unfortunately, our current school gun violence prevention approach almost exclusively centers reactive strategies that are in place to respond to acts of gun violence in the moment, rather than preventive strategies that would prevent them from occurring at all. Reliance on these strategies alone, however, is not sufficient. In line with the core tenets of public health prevention and the Whole School, Whole Child, Whole Community model, we present a more expansive school gun violence prevention framework that broadens the spectrum of what constitutes "school gun violence prevention." Our work highlights how enhancing basic neighborhood and school structures-including investments in public libraries, affordable housing, and universal school-based violence prevention programs-are key to both preventing gun violence and promoting well-being. We also highlight the role of stricter gun laws, reasonable school security efforts, bystander interventions, building awareness within school communities, and meaningful investments in early interventions and mental health services. Children, who have been tragically exposed to any number of adverse experiences in the wake of the COVID-19 pandemic, deserve more reasoned choices and large-scale investments in understanding and cutting off the root causes of school gun violence; not just a reliance on strategies that focus on what to do in the moment of a violent act. As gun violence in K-12 schools persists, we must reframe the discourse about school gun violence around prevention, not reaction.

Simulating the bounds of plausibility: Estimating the impact of high-risk versus population-based approaches to prevent firearm injury

BACKGROUND

Firearm violence remains a persistent public health threat. Comparing the impact of targeted high-risk versus population-based approaches to prevention may point to efficient and efficacious interventions. We used agent-based modeling to conduct a hypothetical experiment contrasting the impact of high-risk (disqualification) and population-based (price increase) approaches on firearm homicide in New York City (NYC).

METHODS

We simulated 800,000 agents reflecting a 15% sample of the adult population of NYC. Three groups were considered and disqualified from all firearm ownership for five years, grouped based on prevalence: low prevalence (psychiatric hospitalization, alcohol-related misdemeanor and felony convictions, 0.23%); moderate prevalence (drug misdemeanor convictions, domestic violence restraining orders, 1.03%); and high prevalence (all other felony/misdemeanor convictions, 2.30%). Population-level firearm ownership was impacted by increasing the price of firearms, assuming 1% price elasticity.

RESULTS

In this hypothetical scenario, to reduce firearm homicide by 5% in NYC, 25% of the moderate prevalence group, or 12% of the high prevalence group needed to be effectively disqualified; even when all of the low prevalence group was disqualified, homicide did not decrease by 5%. An 18% increase in price similarly reduced firearm homicide by 5.37% (95% CI 4.43-6.31%). Firearm homicide declined monotonically as the proportion of disqualified individuals increased and/or price increased. A combined intervention that both increased price and effectively disqualified "high-risk" groups achieved approximately double the reduction in homicide as any one intervention alone. Increasing illegal firearm ownership by 20%, a hypothetical response to price increases, did not meaningfully change results.

CONCLUSION

A key takeaway of our study is that adopting high-risk versus population-based approaches should not be an "either-or" question. When individual risk is variable and diffuse in the population, "high-risk approaches" to firearm violence need to focus on relatively prevalent groups and be highly efficacious in disarming people at elevated risk to achieve meaningful reductions in firearm homicide, though countering issues of social justice and stigma should be carefully considered. Similar reductions can be achieved with population-based approaches, such as price increases, albeit with fewer such countering issues.

Psychotic symptoms in mass shootings v. mass murders not involving firearms: findings from the Columbia mass murder database

BACKGROUND

Mass shootings account for a small fraction of annual worldwide murders, yet disproportionately affect society and influence policy. Evidence suggesting a link between mass shootings and severe mental illness (i.e. involving psychosis) is often misrepresented, generating stigma. Thus, the actual prevalence constitutes a key public health concern.

METHODS

We examined global personal-cause mass murders from 1900 to 2019, amassed by review of 14 785 murders publicly described in English in print or online, and collected information regarding perpetrator, demographics, legal history, drug use and alcohol misuse, and history of symptoms of psychiatric or neurologic illness using standardized methods. We distinguished whether firearms were or were not used, and, if so, the type (non-automatic v. semi- or fully-automatic).

RESULTS

We identified 1315 mass murders, 65% of which involved firearms. Lifetime psychotic symptoms were noted among 11% of perpetrators, consistent with previous reports, including 18% of mass murderers who did not use firearms and 8% of those who did (χ2 = 28.0, p < 0.01). US-based mass shooters were more likely to have legal histories, use recreational drugs or misuse alcohol, or have histories of non-psychotic psychiatric or neurologic symptoms. US-based mass shooters with symptoms of any psychiatric or neurologic illness more frequently used semi-or fully-automatic firearms.

CONCLUSIONS

These results suggest that policies aimed at preventing mass shootings by focusing on serious mental illness, characterized by psychotic symptoms, may have limited impact. Policies such as those targeting firearm access, recreational drug use and alcohol misuse, legal history, and non-psychotic psychopathology might yield more substantial results.

Firearm Homicide Incidence, Within-state Firearm Laws, and Interstate Firearm Laws in US Counties

BACKGROUND

Firearm homicides occur less frequently in US states with more firearm control laws. However, firearms are easily transported across state lines, and laws in one location may affect firearm violence in another. This study examined associations between within-state firearm laws and firearm homicide while accounting for interference from laws in other nearby states.

METHODS

The units of analysis were 3,107 counties in the 48 contiguous US states, arrayed in 15 yearly panels for 2000 to 2014 (n = 46,605). The dependent measure was firearm homicides accessed from the Centers for Disease Control and Prevention (CDC) Compressed Mortality Data. The main independent measures were counts of firearm laws and the proportion of laws within categories (e.g., background checks, child access prevention laws). We calculated these measures for interstate laws using a geographic gravity function between county centroids. Bayesian conditional autoregressive Poisson models related within-state firearm laws and interstate firearm laws to firearm homicides.

RESULTS

There were 172,726 firearm homicides in the included counties over the 15 years. States had between 3 and 100 firearm laws. Within-state firearm laws (incidence rate ratio [IRR] = 0.995, 95% confidence interval [CI] = 0.992, 0.997) and interstate firearm laws (IRR = 0.993, 95% CI = 0.990, 0.996) were independently associated with fewer firearm homicides, and associations for within-state laws were strongest where interstate laws were weakest.

CONCLUSIONS

Additional firearm laws are associated with fewer firearm homicides both within the states where the laws are enacted and elsewhere in the United States. Interference from interstate firearm laws may bias associations for studies of within-state laws and firearm homicide.

Death and long-term disability after gun injury: a cohort analysis

BACKGROUND

Gun injury accounts for substantial acute mortality worldwide and many others survive with lingering disabilities. We investigated whether additional health losses beyond mortality can also arise for patients who survive with long-term disability.

METHODS

We conducted a population-based individual patient analysis of adults injured by firearms who had received emergency medical care in Ontario, Canada, from Apr. 1, 2002, to Apr. 1, 2019. Longitudinal cohort analyses were evaluated through deterministic linkages of individual electronic patient files. The primary outcome was death or subsequent application for long-term disability in the years after hospital discharge.

RESULTS

In total, 8313 patients were injured from firearms, of which 3020 were injured from intentional incidents and 5293 were injured from unintentional incidents. A total of 2657 (88.0%) patients with intentional gun injury and 5089 (96.1%) patients with unintentional gun injury survived initial injuries. After a mean 7.75 years of follow-up, patients surviving intentional injuries had a disability rate twice as high as patients surviving unintentional injuries (19.7% v. 10.1%, p < 0.001), equivalent to a hazard ratio of 2.01 (95% confidence interval 1.80-2.25). The higher risk of long-term disability for survivors after intentional gun injury was not explained by demographic characteristics, extended to survivors treated and released from the emergency department, and was observed regardless of whether the incident was self-inflicted or from interpersonal assault. Half of the disability cases were identified after the first year. Additional predictors of long-term disability included a lower socioeconomic status, an urban home location, arrival by ambulance transport, a history of mental illness and a diagnosis of substance use disorder.

INTERPRETATION

Our study shows that gun death statistics underestimate the extent of health losses from long-term disability, particularly for those with intentional injuries. Additional and sustainable follow-up medical care might improve patient outcomes.

Examining mass shootings from a neighborhood perspective: An analysis of multiple-casualty events and media reporting in Philadelphia, United States

Identifying the people and places affected by mass shootings depends on how "mass shooting" is defined. From the perspective of urban neighborhoods, it is likely the number of people injured within a proximate time and space, which determines the event's impact on perceptions of safety and social cohesion. We aimed to describe the incidence of "neighborhood" mass shootings in one US city and to determine how these events were communicated to the public through news media. This mixed-methods study analyzed Philadelphia, Pennsylvania police data from 2006 to 2015. Using rolling temporal and distance buffers, we isolated shooting events involving multiple victims within a defined time period and geography. Selecting a definition of neighborhood mass shooting consistent with other common mass shooting definitions in which ≥4 victims were shot within 1 h and 100 m, we identified 46 events involving 212 victims over 10 years. We then searched public news media databases and used directed content analysis to describe the range and headline content from reports associated with the 46 events. Neighborhood mass shooting victims were more likely to be younger and female compared to other firearm-injured individuals (p < 0.001). Seven (15%) events received no news media attention, and 30 (77%) of the 39 reported events were covered solely in local/regional news. Only one event was named a "mass shooting" in any associated headline. In Philadelphia, neighborhood mass shootings occur multiple times per year but receive limited media coverage. The population health impact of these events is likely under-appreciated by the public and policymakers.

Extreme Risk Protection Orders: An Opportunity to Improve Gun Violence Prevention Training

States are increasingly enacting extreme risk protection order (ERPO) laws, also known as "red flag" or gun violence restraining order laws, as one part of a multidisciplinary approach to address the national gun violence epidemic. Passed into law in more than 10 states and under consideration by legislatures in approximately 30 others, ERPO laws create a legal process to temporarily remove firearms from people who may pose a risk to themselves or others. By enabling family or household members, law enforcement, and, in some cases, health care professionals to petition courts when they are concerned about a potential crisis, these laws can potentially prevent firearm-related violence and save lives. Most states with ERPO laws do not give health care professionals a direct role in filing petitions; still, physicians may serve as a resource for patients or their families by counseling on firearm safety and raising awareness of this legal pathway. In this way, the success of ERPO laws depends, in part, on the ability of physicians to accurately assess risk. However, physicians are often not proficient in making these types of risk assessments, largely because of insufficient training, particularly in the context of firearm-related violence. The authors review the literature on physician skill in violence-related risk assessment, medical education in gun violence prevention, and the capacity for training to improve such risk assessments. The authors then make recommendations for integrating focused gun violence prevention training into undergraduate, graduate, and continuing medical education, reviewing notable examples.

The Effect of Large-Capacity Magazine Bans on High-Fatality Mass Shootings, 1990-2017

Objectives. To evaluate the effect of large-capacity magazine (LCM) bans on the frequency and lethality of high-fatality mass shootings in the United States.Methods. We analyzed state panel data of high-fatality mass shootings from 1990 to 2017. We first assessed the relationship between LCM bans overall, and then federal and state bans separately, on (1) the occurrence of high-fatality mass shootings (logit regression) and (2) the deaths resulting from such incidents (negative binomial analysis). We controlled for 10 independent variables, used state fixed effects with a continuous variable for year, and accounted for clustering.Results. Between 1990 and 2017, there were 69 high-fatality mass shootings. Attacks involving LCMs resulted in a 62% higher mean average death toll. The incidence of high-fatality mass shootings in non-LCM ban states was more than double the rate in LCM ban states; the annual number of deaths was more than 3 times higher. In multivariate analyses, states without an LCM ban experienced significantly more high-fatality mass shootings and a higher death rate from such incidents.Conclusions. LCM bans appear to reduce both the incidence of, and number of people killed in, high-fatality mass shootings.